This article is about the installation of a 20 kw solar system. The article explains everything you need to know and more about the installation of one of our reviewers.
There are a lot of reasons I decided to have a big honkin’ solar array installed on my roof. I’ll get to the tangible ones shortly—backed by cold, hard data. The main reason that comes to mind, though, is less concrete. It’s a feeling, or an instinct; a desire to realize the expectations of my 20th-century childhood as a 21st-century adult. This is something I’ve wanted even before I plopped down my first solar power plant as an 11-year old SimCity 2000 mayor. My infatuation with solar arrays has grown. Home Solar Generating System
![20 kW solar system: Full Installation Walk-Through](http://cdn.globalso.com/bicodi/1.png)
Now, I understand that the emotional investment I have in this venture isn’t something everyone is going to share. Still, it’s an undeniable factor in my decision-making process. My parents were promised an inevitable fusion–powered, robot–filled, smart–home by science fiction when they were kids. Hanna-Barbera’s vision of the future may not have come to pass, but I want my daughters to grow up in that futuristic fantasy, so it’s up to me to deliver on that dream.
Beyond being simply a cool toy that I’ve wanted since I was a kid, or a sound investment I can make now that I’m all grown up, I consider this project to be a personal moral imperative. That may be a ironic phrase to invoke for what should be a by-the-numbers adventure, but I was happy to find that both my wallet and my conscience would be soothed by this endeavor. The math works out, but I’ll add this much: I’ve already left my mark on the planet, and now I want to erase it. I think this is a good start.
As any adventure should, I began with research. Question number one was, “does solar power even make sense in Michigan?” Following closely behind, there was a second question of “exactly how large of an installation would I need?” There are tons of calculators online for finding those answers, and I used more than a few to get multiple opinions. Ultimately all the numbers really clicked for me once I saw the map below. It breaks down solar irradiance into kWh-per-kW-of-panels-installed, per year.
That image is backed up by the feds and other resources online. You can see that Michigan’s 1400 kWh/kW-yr ranking isn’t amazing, but it isn’t tragic either. Since my goal was to offset 100% of my electrical consumption with solar energy, the math here is pretty easy. All I had to do was add up my annual kWh usage based on my electrical bill, then solve for X. In 2018, our household included an entire extra family for eight months. That lead to an over-the-top electrical consumption of 25,650 kWh for the year. In 2017, our usage was more normal, clocking in at 20,263 kWh. Overkill is underrated, so I used the total from 2018 for my calculations. Also, solar panels lose about 0.5% of their production each year—another reason to aim high.
A solar panel system’s capacity is expressed as its peak potential output, or kWp. I divided my consumption of 25,650 kWh by the 1400 kWh/kW-yr from the map and came up with a requirement of an 18.32 kWp system. The calculations aren’t quite that easy, though. There are other factors to consider, like the laws of physics. Any system is going to have efficiency losses. Roughly speaking, you’re talking about needing an extra 20-25% more capacity to counter those losses. That brings my requirements up to 22.9 kWp for my 2018 numbers and 18.09 kWp if I look back to my 2017 usage. With that, I had my rough estimate.
Of course, there’s still more to it than that. There’s potential shade to consider, as well as the directions the panels are facing, and the pitch of your roof. Those variables are a bit too specific to be within the scope of this piece, though. Just know that they will come into play when you start fooling with full-fledged solar calculators online. In my case, you’ll soon see that shade was not a problem for me. I do however have an east-west facing roof instead of a the idyllic southern facing one. As it turns out, that’s not nearly as significant a factor as it used to be with today’s modern panels and their prices.
Speaking of problems—Fish, you idiot. The. Sun. Goes. Down. That’s where “net metering” comes in, though. Net metering means you can bank credit with your power company when you produce more power than what you’re using. Think of it as using the electrical grid as a battery, at least financially. Alternatively, think of it as old-school rollover minutes on your cellphone. You’ll have to do your homework to see if it’s available where you live, but it made everything a lot easier (and cheaper) for me.
Net metering is critical, because unless you plan on storing all the excess power yourself (more on that later), any solar panel array you invest in is only going to lower your bill while it’s actively generating power. You’ll still be drawing from the grid when it’s dark, cloudy, or when the panels are covered in snow. Without net metering, there would be no point to installing a system capable of producing more power than you use during the day. The bottom line is that with that ability, you can install whatever size system you want without having to worry about what to do with the power you’re not using in real time.
Number of minutes between sunrise and sunset for my latitude and longitude. Source: USNO
In my case, the type of net metering at my disposal means that any excess power I produce in a month carries over to the next month as a credit on my bill. I don’t get paid cash for producing more power than I need, but the credit stays on my account for 12 months. At that point, any surplus I may still have drops off. It’s early days yet for my system, but my hope for this year is that I’ll bank up enough credit over the spring, summer, and fall to be able to get through next winter (when the panels are covered with snow) by pulling from my credits. We’ll talk about how that’s working out so far in a bit, and my intention is to revisit that specific topic six months from now, and again six months after that.
After my research, I had a rough idea of what size system I needed to generate my annual power requirements. I also knew that, even though I’m not afraid of some DIY work, this was more project than I could handle without help. It was time to get some quotes and figure out if my plan was even remotely practical. I mentioned that there are lots of solar power calculators online, but there are also a number of services that will collect your details and share them with installers so they can produce bids for the job. I ended up using EnergySage for this step in the process and I highly recommend it. Answer a few questions, share a recent electric bill, and then sit back and wait.
After a week or so, I ended up with quotes from three different installers, all of them operating within about four hours of where I live. EnergySage’s portal summarized the quotes and made them easy to compare. It also audited them to a degree, playing the role of a third-party fact checker. The portal provided a means of communication with the installers that didn’t require me to share my direct contact info, which was welcome for the early stages of dialogue with them. All the quotes ended up in the same ballpark for cost and payback, but there were some differences. Each installer had their own preference for what brand of hardware to use and how much of it would be needed. The warranties differed too, both for the hardware and for the labor.
After engaging everyone in conversation for a couple weeks, I fleshed out the quotes by adding a critical load panel and requisite battery to them. I ultimately chose Strawberry Solar to do the job based on its combination of price, warranty, responsiveness, reviews, and its choice of hardware. I’ll say this upfront: Strawberry was and continues to be a pleasure to work with. If you’re interested in a solar project of your own, and they’re a candidate to do the job, I highly recommend the company.
The process that lead to signing on the dotted line revealed one reason the quotes I got were so similar. It turned out that based on my electric usage, the system my household demanded was hitting the 20 kWp cap for residential solar power in Michigan. Even if that weren’t the case, any effort to go higher than 20 kWp would result in a “Category 2” program where I couldn’t get a credit for my power delivery rate, only for the supply rate. You can read details about that here, but it’s specific to my power company and could vary elsewhere. At any rate, the 20.13 kWp system that Strawberry landed on was right in the middle of my own estimate of 18-23 kWp, which was fine by me. The 20 kw solar system would be installed.
As things worked out, the system Strawberry installed ended up being 20.46 kWp. That number is reached by multiplying the 62 panels on my roof by their rated peak performance of 330 W each. The original quote was for 61 panels, but Strawberry tossed in a freebie to make the array look nicer. As it turns out, the installers were just as excited about setting up a big honkin’ system like mine as I was. I asked about the size of the system putting me over the limit for “Category 1” net metering, but I was assured that inefficiencies in switching DC to AC power meant that having slightly over 20 kWp in panels was not a problem. In fact, the two inverters in my basement only total up to 19 kW anyway.
Speaking of the inverters, let’s dive into the specifics a bit. Fair warning: this won’t be a technical deep dive. It’s just to whet your appetite with an idea of what one of these systems looks like, and what, uh, powers it. A lot of new stuff got added next to the existing electrical panel in my basement. There’s a new meter, a transformer, two inverters, a critical load panel, a box for breakers that allows both inverters to charge the battery, the battery itself, and a large raceway full of wires that connect everything together. We’ll take a quick look at each piece.
The meter is an unassuming box with an important job: it tracks incoming and outgoing power from the grid. It’s also responsible for making sure that power from the system doesn’t feed back to the grid when there is an outage, ensuring the safety of folks working to restore power. The transformer handles switching the DC power from the battery into AC power that can be used by anything connected to the critical load panel during a power outage.
The critical load panel doesn’t have any particular smarts; it’s just full of normal breakers. However, in the event of a power outage, the items hooked up to it will continue to run, either directly from solar power coming from the inverters or from the big battery, by way of the transformer. Regardless of how much solar energy is being produced, only the critical load panel will have power during an outage. We’ve got our sump pump, furnace, refrigerator, a circuit that power’s Ellie’s room, and our cable modem and router hooked up to it. In the event of an outage, the basement will stay dry, the house will be warm, food’s chilled, Ellie’s humidified, and battery-powered devices online.
The battery itself is an LG Chem RESU, and it can store 9.8 kWh. Based on the loads it sees, that should be enough to last through most nights until the panels can take over and charge it up during the day. Hopefully, we don’t have to deal with many outages that last that long, though. I can’t stress enough how much peace of mind having the battery in the system gives me. Even if it was just for the sump pump alone, it would save me a ton of stress. In the worst-case scenario, it’s a huge buffer between when the power goes out and when I need to fight with the generator.
9.8 kWh ought to be enough for anybody.
We have the battery configured so that power is not typically drawn from it unless there is an outage. It could be configured in such a way as to minimize our power draw from the grid, but thanks to net metering, that isn’t a big concern for me. Instead, I’d rather make sure the battery is always topped off and ready to go in the event of an outage. The controller maintains the battery by automatically cycling it to optimize its lifespan.
When the system was first powered on, the battery was only 20% charged. I watched in astonishment as it drew 5,000 W directly from the solar panels to charge itself at the rate of about 1% a minute. It was nuts! So far, we’ve only had one small power outage to let us see what the battery could do. Everything worked exactly as planned, which ended up meaning the critical load panel ran directly from the solar panels and never touched the battery. Daytime outages: solved. I continue to be both nervous and excited to see what happens during a longer outage when it’s overcast and rainy the next day. Will the battery make it through the night? Will the panels be able to charge it the next day? I don’t want the power to go out, but I do want answers to those questions.
The cat room will never be the same.
Finally we get to the inverters, a SolarEdge SE11400 and a SolarEdge SE7600. They are 11.4 kW and 7.6 kW respectively, totaling up to the 19 kW I mentioned previously. They are attached directly to the Canadian Solar panels and SolarEdge power optimizers on the roof. By the way, mad props to the electricians that hooked all this gear up. It’s so organized, and I think it looks awesome. They also managed to fish the wires from the roof-mounted panels through the roof, down an interior wall, and into the basement without so much as a single hole in any of my drywall. Very impressive.
The installation of all the hardware in my basement took about three eight-hour days for two electricians. That happened after four people spent two eight-hour days installing all of the panels on the roof. Since I was never up on the roof myself, I’m not going to go into great detail about the installation process, but I will say that I know they used hardware from IronRidge and that everything on the roof was drilled right into the trusses. The flashings that were used were tucked under the roof’s shingles and sealed with tar on the bottom. No worries about leaks here.
Did I mention that the installation was originally scheduled for the week of the great 2018 polar vortex? Yeah, we had to reschedule it for the following week, but it was still wet, bitter cold, and windy. The install team were beasts. Here’s a few pics of the initial install.
I’ve also got a video from the deck on the other side of the house right after they finished putting the panels up.
Here’s some obligatory drone footage as well; more of that to come.
That’s a fair question. Let’s break down the costs, and compare them to my electric bill for a rough idea of what the ROI looks like. I’m not going to pussyfoot around—this is hard data, albeit with slightly-rounded numbers for simplicity. The complete system cost $65,000. I’ve been planning on this for a long time and was able to pay $15,000 down. We got a home equity loan for the remaining $50,000. It’s a 12-year loan with payments of $475 a month. My family-heavy electric bill averaged $350 a month last year, and in 2017 it averaged $275 a month. If you take the absolute worst-case scenario where electric costs don’t go up, I don’t pay off the loan early, and we use the 2017 bill for comparison, the system will pay for itself in 27 years. Oof.
Thankfully, that’s not how things are going to go down. For one, and this is a big deal, there’s currently a 30% tax credit from the feds that you can claim for solar projects. That works out to $19,500 in taxes that I don’t have to pay until it’s used up. By the way, and this is also a big deal, 2019 is the last year that tax credit is 30%. Next year it drops to 26%, and it only gets lower from there until it’s gone. You can only claim the credit if your system is installed and operational before the end of the year, so get cracking if you’re interested, because it will take a least a few months to get one in place.
With the tax credit as part of the equation, the EnergySage portal produced an estimated payback date of 8-10 years based on the data I fed it once they had my quotes. It gets speculative from here, because my electrical consumption is lower than what I advertised, and I plan to pay off my 12-year loan in closer to four years to avoid much of the interest. My best guess is that if my electrical consumption remains the same and electrical costs remain the same, I would get a full return on the investment in close to 14 years.
However, I expect to use more power as time goes on (an electric car is up once the solar loan is paid off), and electrical costs will rise, so 10-12 years seems a more likely timeframe. Of course, the system is going to last another 20 years or so beyond that. Minus some maintenance costs, everything it saves after that is money in the bank. By the time the system reaches its end of life, it will not only have paid for itself, but it should also have saved me well over $100,000. In 2052, that could be enough money to get my inevitably decrepit 70-year old body to Mars and turn it into fertilizer. I’m more than half-serious. I can hear my future-self pontificating now: “your ironically named Mr. Fusion may run off Bananorango® peels but my antique solar panels still charge my exoskeleton just fine, dagnabbit!”
Anyway, that’s the situation for me. A lot of things could be different for you, and I encourage you to look into your options. Much of the pitch for solar that you see is that you can straight-up trade your electric bill for a loan payment. That’s definitely not true in my case, but it certainly could be for others or, even for me if I had done things differently.
With all the exposition out of the way, we can finally get to how the system is performing. For only having it producing power for a couple months, I feel like I’ve seen it running in a pretty wide range of conditions. It handles some situations better than others, but overall it’s outperforming my expectations, especially in inclement weather. No, it doesn’t magically produce power when the panels are completely covered in snow, but in cloudy, rainy, or snowy weather it manages to generate a surprising amount of energy nonetheless. All the details regarding production are visible through the SolarEdge web portal and companion app. Check it out:
I spend an unhealthy amount of time staring at “my numbers.”
This is my data. Isn’t it lovely? I think the numbers speak for themselves, but to summarize, it shows me everything about how much power is being generated and consumed in near-real-time. I can see my various totals for the day, week, month, and year. It even shows me the state of my battery since one of the inverters is its boss. The data in this image is from 14:30, near peak time for production. You can see that the system is absolutely obliterating the household’s meager demand for power and is putting 85% of the power being generated back onto the grid. This will be a common theme.
This screenshot is from a different day, but the story is largely the same. The partial graph above begins to tell the story of how net metering and my geographical location need to work together. Simply put, I’m not just looking at things on a day-to-day basis. In order for my system to completely eliminate my electric bill, I need it to cast a wide net and catch as much sun as possible whenever the opportunity presents itself. Generating two, three, or maybe four times as much power as I need in 24 hours is necessary to bank up enough credit to get through the months of the year where the panels are unlikely to see much sun at all thanks to the snow.
Before you ask, it’s generally frowned upon to clear snow off panels. They are hard to reach and there’s a non-negligible chance of damaging them, but it can be done if you’re so inclined. If they aren’t covered in snow, they actually perform better in the cold. Hooray for silicon!
The panels on the top are facing west, so I guess it must be past noon.
On the “layout” page of the portal, you can see the arrangement of the panels on the roof and get both real-time and historic performance data per individual panel. It’s extremely cool, but it’s also a bit flakey. I’m still working with Strawberry and SolarEdge to make sure everything with this reporting tool is working correctly with my setup, because I sometimes see unexpected numbers here. That said, it’s clearly only a cosmetic problem, because the system is generating power correctly and the reported totals align with what my power company is seeing from its meter.
Just a little bit of power coming in where the snow has melted.
One of the coolest things about the SolarEdge portal—and the reason I didn’t cover it in more detail—is that you can make the data for your installation publicly available. That’s exactly what I’ve done, to the full extent that I can. Use this link to go directly to my own personal site, nicknamed Sunfish. You can also browse other public sites here. You won’t be able to see exactly the same information I can, but you can view real-time performance, the layout of the panels, and all the historical data any way you want to slice it.
That feature is nice and it was real easy to set up, but I wanted to give gerbils more than just graphs. I wanted them to see the weather that goes with them, so I settled on procuring a dedicated time lapse camera with a weather resistant housing and making sky-watch videos with a performance graph overlay. Here’s an example of what I ended up with.
I’ve got a growing playlist here if you want to check out more. I thought it was important to show people exactly how the performance of solar power matches up with what’s going on in the sky. I intend to keep adding to this playlist in batches—the camera is outside 24/7, and I’ll pull the daily videos off it once a week or so. How long I’ll keep this running will depend on how interesting people find it, so let me know what you think and please share it if you find it worthwhile. I have no shortage of ideas for other uses for the camera, but I’ll keep it pointed at the sky if people are enjoying the view off our back deck. Personally, I’m excited to string a bunch of these videos together later in the year and produce a high-speed playback of the field growing up.
Speaking of views, it’s about time I shared a proper look at the fully installed system. Here’s some more drone shots.
I had this project in mind when we bought this house close to four years ago. Even at the time, I knew that a large, southern-facing roof would be more ideal, but after checking out those photos, I’m pretty sure you’ll agree that the house was a pretty good candidate for roof-top solar regardless. There’s no shadow cast on the roof from anything on the ground, and since the panels face east and west, they collect sun early in the morning and they do late into the evening. The best times for production change throughout the year, but right now in late April, the peak appears to be happening from 13:15 to 14:15 when the panels on both sides of the roof are collecting energy at the same rate.
Here are a couple more videos for additional perspective.
Again, you can really see how our house sticks out of the small peninsula of a private drive, right out into the middle of open fields with no trees or buildings blocking the sun. We’re not even close to the longest days of the year yet, and my panels are already generating more power than the house is using from about 08:00 to 20:00, if there aren’t too many clouds. I love it.
Speaking of the weather, I’ve never been more in-tune with it, nor have I ever appreciated sunshine more (or, you know, at all). Everyone knows about the weather rock, but my solar panels actually work similarly. I can look back through my SolarEdge data and tell a lot about how the weather must have looked that day. Increasingly, I’m able to see the weather forecast and predict how many kWh the system will likely produce.
It’s a fun new aspect of conversation to have around the house as well as at the office, where some of my coworkers are nearly as obsessed with my numbers as I am. As a side note, my system inspired one of my coworkers to install 6.4 kW of panels on his own home. He’s taking a DIY approach and won’t have it finished for a few months, but his investment will probably be less than half the dollar-per-kW price tag of my professionally-installed system. Just something to keep in mind if you’re handy enough.
Over a month ago, we put up a poll asking folks what their household’s average kWh usage is. Even though the results of any online poll should be taken with a massive helping of molten salt, I feel confident that my vote of 61-75 kWh definitely places me in the upper echelons of power usage. Even if we only look at the close-to-40-kWh average that my house has used through March and April, I’m still above average for gerbils. The nice thing about solar projects like mine is that they scale pretty well, and as long as your roof has a clean view of the sky, the ROI is probably similar no matter where your usage falls. I suppose what I’m trying to say is that the concept is worth at least looking into, especially when the feds will give you a 30% tax credit.
This story isn’t over, not by a long shot. I’m only two months into a 30-year-long endeavor. My biggest takeaways so far are that in less than 60 days I’ve produced 60% more power than I’ve consumed, and I’ve exported a little over twice as much as I’ve imported. Funnily enough, I’ve become so cognizant of my power consumption that I’m using measurably less even though I have a significant surplus.
That all feels good, but I’ve yet to turn on the AC this year, and that will certainly have a dramatic impact on usage. The same lack of shade that makes my house good for solar also makes it a bear to keep cool. I hope that with longer days coming, I’ll be able to continue building up my electricity credit despite the need for AC, and get myself through the winter without paying for power. I didn’t have an electrical bill for March, and I won’t have one for April. I’d love for that to be true for every month going forward.
That’s one huge reason for doing this, after all. Well, that and zombie preparedness. I have no illusions of surviving a zombie apocalypse—rule #1 is a problem—but that doesn’t mean my house can’t be an electric oasis for someone else.
I’m less than half-serious about that one.
I’m going to revisit this story at least twice more: once after the summer is over, and again after next winter. I’m looking forward to sharing stories of production records being broken (125 kWh is the number to beat so far), the LG battery backup saving the day, and filling in some of the other details I haven’t gotten to in this first brush with the topic. If you found what I’ve shared so far valuable or at least interesting, please share it with others and let me know what you think. I’ll check in with you again in October.
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So my coop charges $35-$37 a month for providing service. Also, another $4.78 per kw (solar size on house), max $57.17 a month for grid access fee. After the FEES that would eat up any and all excess power produced IMO. At that point you are not making money from excess production, but would need to think of the coop as a backup for if your system goes down. At that point maybe it would make more sense to get an extra battery and go OFF grid.
What do you think the cost would have been for a 15kw system? Just a rough estimate. Using your calculations my home estimate is around 12.5. So let’s say 15kw. Would it have shaved off $10,000?
Could we get a long term update on this project? I’d love to see how your actual production has faired against your projected. Is it on track for your ROI?
In the billing cycle data, what is the difference between “Self Consumption” and “Consumption”? How is “Import” and “Export” calculated (I can’t seem to make the math work out)? Do I assume that “Export” – “Import” represents the kWh being netmetered?
One thing to consider is that every kW that you convert into electricity is a kW you can subtract from your air conditioner’s heat load. Even if the panels were not generating anything, they would be blocking a ton of radiant energy from hitting your house. I expect you are finding that your AC is using significantly lss power than previous years.
Very informative and well-written article. Thanks for providing so much detailed (and personal) information. Whether or not solar is for everyone it’s nice to read a write-up like this.
I got my net metering spreadsheet and April’s power bill today.
$6.84 for the honor of being grid-connected.
$177 in credit toward my next bill.
I’m a happy camper.
Fish, you idiot! What were you waiting for?
Cool, thanks for the update and the article!
Tesla is slashing prices in an effort to drive up volume.
[url<]https://www.cnn.com/2019/05/01/investing/tesla-solar-panel-costs/index.html[/url<] This is coming just after analysts were saying that the price for solar cells might rise again. It could have the effect of making 2019 the best year to go solar for a long time.
“The same lack of shade that makes my house good for solar also makes it a bear to keep cool.”
Nice thick/wide shrubs ( < 8ft tall) along the sides of the house that get the most sun can make a huge difference on cooling in the summer by preventing the walls and foundation and ground close by from absorbing tons of heat, and especially then radiating it into the house at night. If they lose their leaves in winter, even better because then you get the sun back for warmth when you need it. Worth looking into.
Any recommendations on specific plants? From a security standpoint shrubs up against the house aren’t a good idea.
did you assume -no broken or degraded solar panels over that time? -no degraded batteries over payback lifetime? -no defective or failed electrical components of the payback lifetime? -labour to replace anything over payback lifetime that fails out of warranty? -interest lost on investing 65k? -interest paid on the loan?
If one could get 5% on 65k that would be about $271/mo.
i’m planning on eventually setting up a solar array, and hopefully not spend that much cash. it will be a DIY project. i want my panels to be on the ground level for easy cleaning and maintenance , and on dual axis actuators that automatically track and pivot towards the sun to maximize charging my batteries during the day. i do like the idea of also having net metering, as being hooked up to the grid and selling any power excess of what the batteries can hold.
something like this, but slightly bigger. [url<]https://www.youtube.com/watch?v=hr07xKWM6tw[/url<]
While that is decidedly cool and looks like a fun project, what I’ve read is that, generally speaking, trying to min/max a smaller number of panels is not as cost effective as just buying more panels instead. Also, caring for moving parts on a structure being battered by wind and weather sounds like too much maintenance for my taste.
Holy shit! 350$ a month electricity bill! What are you doing in the US?
Here in Germany my parents household is like 120 € / month and thats a lot. My 2 person hosehold uses like 20 € a month.
I know $275/mo isn’t much better. But that [i<]was[/i<] with 12 power hungry people in our house, heh. It goes up the more you use too, our peak bill last year was $555 for July. That works out to [b<]$0.18/kWh[/b<] vs. the $0.15/kWh for this January's $259 bill.
That’s cheap. Germany is flat for like 0,28 € kWh + meter rental fee (btw the gallon fuel is like 5,86 € here).
12 people is a lot! Maybe you should restrict mobile device usage in order to save power 😉
If we took the tablets away from the kiddos it would be chaos beyond imagine. o_0
I doubt that tablets are your main source of power usage.
Heating (electric/heatpump) and Cooling are the main ones and probably 60-75% of the bill. Followed by electric water heaters, dryers and stoves/ranges.
[quote<]It goes up the more you use too, our peak bill last year was $555 for July. That works out to $0.18/kWh vs. the $0.15/kWh for this January's $259 bill.[/quote<] That sucks (goes up the more you use). Here in Texas you can pick your own plan. Some are like what you have but here you can get ones that don't go up the more you use. Infuse Energy [url<]https://www.infuseenergy.com[/url<] Essential Infusion 36 Fixed Rate 36 Months 16% Renewable Facts label: [url<]https://88fd201f32c53c2bd0fb-11ba98ed637230a2314ec7c228a44bda.ssl.cf5.rackcdn.com/201904/EFL-20190422-143214-Essential%20Infusion%2036%20(English).pdf[/url<] Oncor Delivery 9.5¢ - 500 KWh 9.0¢ - 1000 KWh 8.7¢ - 2000 KWH Total bill cost is: 5.290¢ per KWh Energy charge + 3.315¢ per KWh Oncore delivery charge +$2 --- For those who live in Texas you can go 100% Renewable via NEW POWER TEXAS at 9.2¢ per KWh: [url<]https://newpowertx.com/EmailHTML/efl.aspx?RateID=413&BrandID=5&PromoCodeID=0[/url<]
Haven’t kept up with hardware in years and all the new video card and CPU name designations are unknown to me, but this article has me more interested.
I live in Central Florida and one side of my roof faces southeast, perfect to grab the morning rays and avoid losing power generating opportunity when the summer afternoon clouds and rains come.
After some loose calculations I made some 6-7 years ago, I figured that I could outfit the roof and generate at least 75% of my electrical usage. The cost back then was going to be at least $45,000, but now I think that is just about halved today.
One of my neighbors just put panels on his house, and he can monitor everything from his smartphone. He can even tell if one panel isn’t working right and might need to be cleaned or repaired. The panels in his system each come with their own inverter, so there’s no need to match inverters to panels or worry about losing all of his generating capacity if an inverter fails for whatever reason.
Also adding to my calculations is the fact that I work from home 1 to 3 days per week, which would allow me to charge an electric vehicle for as little as 42% and as much as 71% of my prime solar energy production hours.
So I definitely want to go for it. It’s just a question of making the money happen.
The Sunfish dashboard doesn’t show the correct date when the power plant was installed – it shows the current date instead. It’s the same with the other plants at solaredge.com. What’s up?
Weird. It looks like all of them show the current date. On my logged-in panel I see the date the system went live, 3/1/19.
Fun read. Thanks for taking the time to post.
Well, now you need a wind turbine to compensate for the lower solar power in the winter!
Believe me, I’ve thought about it. We’ll see how far net metering gets me first, though.
Colton, your case scenario is a good example of why many smart people are now saying that the problem with solar is not that it produces too little electricity at night or in bad weather but exactly the opposite. The problem is that solar panels produce too much electricity for the grid.
[url<]https://www.technologyreview.com/s/611188/california-is-throttling-back-record-levels-of-solarand-thats-bad-news-for-climate-goals/[/url<] [url<]https://www.smh.com.au/business/the-economy/too-much-of-a-good-thing-solar-power-surge-is-flooding-the-grid-20180606-p4zjs7.html[/url<]
Totally agree. Fortunately, I think it’ll be awhile before Michigan has insurmountable problems of that nature. If it becomes a problem, I can always add a second battery (the LG is designed to run as a pair) and switch gears to using my own stored power regularly instead of just as a backup.
You should invest in an electric car, A Tesla Model 3 would be my suggestion. You generate a ton of kw per day and the car battery is 75kW so you can basically have free transportation. You are light on the battery, it’s sufficient for home usage though.
It’s on my list.
Honda Clarity is on my electric car list. 47-miles all electric, 300-mile gas tank.
When you run out of electricity, it uses a gasoline engine to charge the battery. Its pretty much a “normal” car that happens to be able to be charged with electricity. Still got the $7500 federal tax credit too (Tesla is losing their credit, only $3750 right now, and it will drop again in a few months)
It will be interesting to see what the landscape looks like in 4 years or so. At the moment, I’m thinking a plugin hybrid, but maybe all electric will be the way to go by then. 100 miles of range would be enough for me 99% of the time, 50 miles probably 90%. Current 200-300+ ranges would be good enough for all but maybe one or two trips a year.
[quote<]100 miles of range would be enough for me 99% of the time, 50 miles probably 90%. Current 200-300+ ranges would be good enough for all but maybe one or two trips a year.[/quote<] Roughly the same calculations as me. 50 miles covers my typical working day, but it would be pushing it when I do errands after work. I'd estimate maybe 2 or 3 times a week I'd go over 50 miles (work -> groceries -> help my sister's kids -> home) 100 miles covers almost every use case I can think of, except for vacations (which 300+ range won't cover either). There's a bunch of plug-in hybrids with lol 20-mile electric range (Toyota Prius), but that's not even enough for me to go to work and back each day. 50-miles covers my typical daily driving behavior. So that's why I like the Honda Clarity / Chevy Volt.
The other thing I’m waiting for is something more like the formfactor of my beloved Rav4. I’m still driving a 2003 model and it’s a perfect fit for what we need. Ellie’s wheelchair fits great in the back of my Rav, but it wouldn’t fit in a sedan’s trunk. Similarly, I can put the dogs in the back of the Rav and keep them away from any of the seats, which are usually occupied by car seats for Ellie and Wren.
I don’t want a big honkin’ SUV or need a minivan, but I can’t get by without a [i<]bit[/i<] of extra space.
Hmm, Model X is around RAV4 size (slightly shorter but slightly longer), but its also a $100k vehicle.
Yeah, its probably best to wait a few years. I know “Rivian” is building a “large skateboard” for various car manufacturers to use as a large electric car base. They’ve got contracts with Ford (and at least… used to have a contract with GM). There are a bunch of rumors about how their vehicles will look like, but nothing seems official yet.
I think Rivian is going for large-SUV or truck market though. Not really the crossover size of a RAV4. Then again, its just a “skateboard”, Ford / GM / etc. etc. will have to fill out the rest of the car as necessary, so maybe something like a RAV4 will come out of it in the future.
Consider a Model Y, it comes out next year and has the space you seem to need. I would advise against plug in hybrids, their battery sizes are anemic and a few months down the line you will have buyers remorse, you have a fuel station at home, why would you ever want to visit a gas station again? I have gone through the journey you undertaking now including buying a hybrid.., it leads to a 100% renewable future. You will never look back.
Model Y doesn’t exist yet, and is being built on the Model 3 chassis. The Model Y will be taller than the 3, but we’re looking at an “SUV” that’s comparable to the Ford C-Max (built on top of the Ford Focus chassis). I dunno, maybe its worth looking into, but these “SUVs” that are build on top of a sedan chassis have always been noticeably smaller than a properly built crossover like the Model X or RAV4 (or a [b<]real[/b<] SUV built on a truck chassis, like a Chevy Suburban) The Model Y is clearly a smaller vehicle to compete in the C-max category, while the Model X is the proper competitor to RAV4 sized vehicles. Tesla is being careful to keep their vehicle lines differentiated. All indications seem to be that the Model Y will be noticeably smaller than the RAV4. Model X is Tesla's competitor to the RAV4 size.
That said, my old Rav4 is smaller than the new ones and it works just fine for us. Seriously, if I can fit the wheelchair in it, it will be in the running.
Plug-in hybrids will probably be a quaint memory in 4 years, that’s a fair point.
A rav4 is 182 inch length, a Model Y is ~186 inch length so CMAX is significantly shorter. X is 198.
Might be a little small for your needs but: [url<]https://www.caranddriver.com/hyundai/kona-electric[/url<]
Hmm, that has potential. Thanks!
You will find that they are very hard to find and buy in the US, especially in non carb states. Look into a Leaf + as well.
The thing about owning a Tesla no one talks about — nightmarish repair delays
[url<]https://www.msn.com/en-us/news/us/the-thing-about-owning-a-tesla-no-one-talks-about-%E2%80%94-nightmarish-repair-delays/ar-AAAJmmj[/url<] [quote<]How long would you say is reasonable time for an auto body shop to fix a car with light body and suspension damage? Two weeks? A month? Two months? Craig Hedges was driving on the Stanford campus on Oct. 27, 2018, when a Toyota Corolla pulled out from a parking space and plowed into his 2016 Tesla Model S. Neither vehicle was moving very fast, but the Tesla sustained front fender and suspension damage and wasn't drivable. So the Burlingame resident had it towed a few days later to Chilton Auto Body in San Carlos, the nearest Tesla-approved body shop and the preferred shop of his insurer, Allstate. Nearly six months later, his Model S still hasn't been repaired. The potentially long wait Tesla enthusiasts face to get their cars fixed after fender benders or worse damage is one of less publicized aspects of owning a Tesla. "When my car got in an accident, it was somewhere in the thirties to be worked on and the last time I had a conversation with someone there a few weeks ago, there was well over 130 Teslas there to get fixed," Hedges said. "Now I think if you're number 130, it's going to be well over a year to get your car back." [/quote<]
You’re not supposed to repair a Tesla but buy another one. Same as with Apple products.
Is that a refundable federal tax credit?
FWIW: We installed a full-solar system on our central Fla home about twelve years ago; our intent had been to mitigate not obviate our electric bill. In an area where electric bills typically run $550/month annualized, ours hovers around $70 … occasionally, an odd month will be much lower. Over the ownership period, our installation has weathered hurricanes, hail, cyclonic-events (mild-ish–TBTG), may I repeat, nasty hurricanes … all without drama. It has already paid for itself, after the various inducements and tax allowances.
Functionally, the HVAC gets a pretty thorough work out throughout the year. Much of a year “features” 90F+ (er, +++) highs and, while lows seldom reach the 20sF, even decadally, winter “grey” days can linger in the low 40s for quite longish spells. (I hasten to add, nothing even remotely approaching the suicide inducing spells of the typical Adirondack (see below) winter!)
We, anticipatively, re-roofed with uber-shingles pre-solar install. Our maintenance costs have entailed a tri-annual panel wash (Palmolive liquid) — featuring an hour of quality “ladder time.” We deemed our solar domestic hot water panel (single) to require replacement this year; it had degraded to not regularly providing 125F nighttime tank temperatures. Needless to say, the DHW system includes a quite large Rheem tank; IMHO, “large” is far too small…!
From our experience, here, we decided against “going solar” on either of our northern homes (extreme northern Adirondacks and Pittsburgh). Were we starting, there, with a clean slate, scratch build, it might make some sense, however, given “old construction” and “cheap” heating oil, the numbers would never “work out.” Hmm. Hell, neither of us, likely, has enough years left in our “tank” to even contemplate such hare-brained ventures….
Is the extra weight of the solar panels a consideration one needs to investigate, particularly with a snow load too? Do the installers look at the construction of your roof supports during the quote process perhaps?
Part of the quoting process was to establish the age of the house, I assume part of that is to understand the building codes it was built to. None of the potential installers had concerns about my roof and the weight is distributed to a very low PSI.
Great article! Obvious that a lot of work went into the write-up and editing, and the information is presented in a clear, helpful way.
Very nice. You might look into replacing your gas furnace/electric cooling system with a heat pump based one. There’s still a federal credit for it..and some states also provide rebates/credit. As you are generating your own power during the day, some judicious time-shifting for household temp control could make it a speedy payback.
Also, I’m surprised by the macro inverters. I thought installations were all moving toward solid state micro inverters (better efficiency, longer warranties). What was the thought process from the installers?
Once I have a year of perspective under my belt, I’ll definitely be exploring those options with whatever power budget I have to spare. I’m going to work the system for everything it’s worth, I don’t want it to be overkill forever, heh.
I got the impressing that for an install my size the macro inverters were more cost-effective. TBH, I ran with a lot of their suggestions after confirming they weren’t completely off the mark. It’s all about balance/compromise with a project of this scope.
Micro inverters seemed like a [i<]great[/i<] way to get started if you wanted to do a smaller install, or just dabble a bit with the concept DIY-style. Easy to just add on a few more panels as needed.
Damn fish, now I wanna marry you 🙂 This was a great article; solar power + drones= win win!
I would love to see more article like this; less common themes but super nerdy/techy.
Thanks man! Sadly, projects like this are inherently few and far between. I’ll continue to share what I can with everyone, though.
[quote<]The complete system cost $65,000. I've been planning on this for a long time and was able to pay $15,000 down. We got a home equity loan for the remaining $50,000. It's a 12-year loan with payments of $475 a month. Thankfully, that's not how things are going to go down. For one, and this is a big deal, there's currently a 30% tax credit from the feds that you can claim for solar projects. That works out to $19,500 in taxes that I don't have to pay until it's used up.[/quote<] Here are the totals from the costs you provide: $475 per month loan payment * 12 months * 12 years = $68,400 $68,400 + $15,000 down payment = $83,400 total cost $83,400 - $19,500 tax credit = $63,900 total cost for 12 years $63,900 / 12 years / 12 months = $443.75 per month ---- [quote<]My family-heavy electric bill averaged $350 a month last year, and in 2017 it averaged $275 a month.[/quote<] So even using your worst case numbers you are paying a [b<]Solar Penalty[/b<] of $93.75 per month or $13,500 over the full 12 years. If you used the $275 per month average from 2017 the [b<]Solar Penalty[/b<] would be $169.75 per month or $24,300 over the full 12 years. Your numbers also do not include any maintenance or repair costs nor any insurance premiums nor factor in the degraded power production during those 12 years. I live in Texas where the sun shines almost all the time and am currently paying 7.6 cents per KWh (on the last few months of a 24 month contract). When I renew it will be going to 8.4 cents per KWh for again 24 months. My home is all electric so heating/cooling is done via a heat pump and the water heater and dryer is electric heat. In 2017 I used 21.197 MWh (Mega watt hours) for the entire year or 1766 KWh's per month at a cost of $133.56 per month. In 2018 I was into Monero coin mining big time on lots of quad servers (each with 8-16 cores each CPU or 32-64 cores per server) doing CPU mining. My average power usage went to 5156 KWh's per month. Costs were $336.66 per month or 7.2 cents per KWh. My mining profits were actually higher than my power costs. So using even my insane numbers from 2018 I would still be saving $107.09 by not using Solar. Having residential solar is a money losing endeavor.
His system includes battery + associated costs (safety mechanism to disconnect power from the mains to protect electric workers). There’s a hefty premium you pay if you want to be self-sufficient when the grid goes down.
[quote<]Your numbers also do not include any maintenance or repair costs nor any insurance premiums nor factor in the degraded power production during those 12 years.[/quote<] Solar panels are expected to last for more than 12 years. [quote<]Your numbers also do not include any maintenance or repair costs[/quote<] Your numbers don't include deprecation (erm... more precisely... you're deprecating to zero too fast...). IE: your house is literally worth more money because you have solar panels on it. 10 years from now, he can sell his house for maybe +$30,000 or so because of these solar panels and recoup a lot of the costs. (Depending on how much technology improves however: there's risk here. If new solar panels come out that are more efficient, maybe it will only be +$20,000 to his home value 10 years from now) Where I got $30,000: Assuming a 20-year lifespan and a linear deprecation curve, his $68,000 system will be worth $34,000 after 10 years. Round down slightly because of advancements in the solar-panel industry. Obviously, this is just a spitball estimate, but its better than no estimate at all. The math isn't quite as simple as you make it out to be. And part of it requires a crystal ball to really figure out. In any case, once you factor in the increased value of the home... and ignore the "premium" battery backup system (totally a luxury item. Awesome, but its very expensive), its a pretty clear cut-and-dry case in favor of solar panels. Its just like any other big-ticket item on a house. If you replace the roof, you advertise that when you sell the house. When you replace the furnace, you also advertise that fact. One issue is that you narrow your pool of buyers by getting solar... (any anti-solar people will stay away from this house now)... but I think there has been enough of a cultural change to take that risk long term now (there are probably more people who'd see solar as a net-benefit rather than a detriment, and willing to pay for the house when the time comes).
You’re right that he’s being a bit rosy in the financial calculation, but he’s upfront about the fact that there is an intangible benefit that he gets from the system that makes it worth it for him. And as dragontamer has mentioned, you are neglecting the fact that the system is itself an asset and has considerable value after the payoff period is over. Even once he stops making payments he will continue to have “free” electricity.
Your basic conclusion that residential solar is not yet cost effective is true, but I think that this article shows how close it’s really getting.
Also, are you sure about your 7.2 cents rate? Where I live in Dallas, the delivery charge is 4 cents or so by itself. Some power companies sell you a rate like 7.2 cents, but when you actually look at your bill, it’s a good bit higher because of delivery charges.
[quote<]Also, are you sure about your 7.2 cents rate? Where I live in Dallas, the delivery charge is 4 cents or so by itself. Some power companies sell you a rate like 7.2 cents, but when you actually look at your bill, it's a good bit higher because of delivery charges.[/quote<] Yes the 7.2 cents per KWh is correct. The total cost of my electric bills over the twelve months of 2018 (which includes ONCOR distribution charges and any taxes and fees) was $4425.64. Dividing that cost by 61,866 KWh's of use results in 7.15359 cents per KWh which I rounded up to 7.2 cents per KWh. I have used a spread sheet since 2004 that tracks my costs per year and per provider. On March 22 of 2017 I renewed with Source Power & Gas at these rates: Renewal Date: 03/22/2017 Plan Name: Source Secure Fixed 24 Contract Start Date: 06/13/2017 Contract Expiration Date: 06/13/2019 Average Price: 7.0¢ per kWh (based on 2000 kWh per month) Term: 24 Months Energy Charge: 3.452¢ per kWh Monthly Fee: $14.95 per bill cycle if < 1,000 kWh or $0.00 per bill cycle if ≥ 1,000 kWh TDU Charges: $5.25 per month and 3.286¢ per kWh (As noted on EFL, TDU charges are subject to change.) Source Power & Gas stopped offering residential plans a few months later but had Cirro take over the plan that I signed up for without any changes. Turned out to be a great deal since electric rates were at an all time low then. What is funny is that the Oncore charges have gone down the last few months and I am now only paying 6.9 cents per KWh. Bill Date: 03/20/2019 1799: KWh's Used $59.82: ONCOR Charge $62.10: Cirro Charge $2.43: Taxes/Fees $124.35: Total Bill $0.069: $$$ per KWh April 2019 was also at 6.9 cents per KWh. Bill Date: 04/18/2019 1877: KWh's Used $129.58: Total Bill $0.069: $$$ per KWh
My math is my best guess, but you missed a couple factors. The biggest one is that I have no intention of taking 12-years to pay off the loan. I mentioned that I expect to do it in 4, that will save a lot of cash (there’s not early payoff penalty). Also, it’s highly likely the electrical costs will rise, but that’s hard to account for precisely.
But you also forgot these costs: Your numbers also do not include any maintenance or repair costs nor any insurance premiums nor factor in the degraded power production during those 12 years.
Also using cash to pay down the loan early does save on interest but then you lose on what that cash would have earned if invested.
I’m just presenting my best guess, I think there are too many factors for me to offer a more accurate estimate. Increased insurance cost was only $140/year. I should have the system oversized enough that degradation won’t come into play financially, but again, I won’t be able to predict that more accurately until I have at least my first year with the system completed. I’ve already padded the estimates I was given by a couple years. Maintenance and/or repair will cost something, hence providing a range for ROI instead of a firm number. Then again, I’ve got a good, long warranty, so who knows?
[quote<]12 years[/quote<] If the system lasts 30 years, then he's literally got free electricity 18 years longer than your 12-year estimate. [quote<]Also using cash to pay down the loan early does save on interest but then you lose on what that cash would have earned if invested.[/quote<] S&P 500's PE Ratio is [url=https://www.multpl.com/s-p-500-pe-ratio<]22.13 at the moment[/url<], which means it will take 22.13 years before the typical S&P500 company makes profits equivalent to the price you payed for the stock. (If you spend $1000 on stocks, it will take 22.13 years, at the current rate, for $1000 of profit to be generated from your equity). Solar Panels will prove to be a better investment than the S&P500 as long as they make a profit before 22.13 years. The PE Ratio is a very good indicator of bubbles and crashes. If stocks rise far above their profit-making abilities (or: if the profit-making abilities of companies crash), then the stock market usually falls as a result. Historically, the S&P 500 has a ~15 PE ratio or so, so the 22.13 PE Ratio is a bit high.
Who can guarantee to live in the same home for 30 years? Who never moves? Who doesn’t change jobs and have to move across the country or another city? Who doesn’t start a family and outgrow their home?
[quote<]Who can guarantee to live in the same home for 30 years?[/quote<] When you spend $68,000 on equipment that's expected to last 30 years, it means that 10 years from now, its still worth $40,000+ or so (subject to local real-estate conditions. Consult with real-estate specialist to understand your local conditions). $68,000 is a rather substantial home improvement investment, so really, it depends on your neighborhood. If all the homes in the neighborhood are $500,000 or so, then maybe +$40,000 for a 10-year old solar array isn't that big of a deal. But if the other homes in the neighborhood are all $200,000, then its a hard sell to try and sell your house for $240,000 because of the solar panels. You don't want to "over-improve" your house above and beyond what your neighborhood can support. That's the thing about long-lasting equipment. You [b<]sell it to someone else[/b<] when you're done with it. No one actually uses the same equipment for 30 years, it gets passed around. ------ Bonus points: there are a **TON** of tax games you can play with home-equity lines of credit. You can dramatically play the tax game and reduce your federal income tax significantly if you play things right.
Of course I can’t guarantee I won’t need to move, but I certain intend to try and stay put. I figure there’s higher odds that we won’t move than that we do.
[quote]Having residential solar is a money losing endeavor.[quote] … For You.
Lol, congratulations on having cheap electricity?
Here in sunny San Diego my solar systems, via PPA, are currently $.17x/kWh. Meanwhile the investor owned utility monopoly has a base rate of $.21-.23/kWh (depending on the month), though the base rate is only for the first ~350kWh/month (again, variable by month). With solar, I’ve never gotten past the first tier.
Once you get past that, the next tier is $.40-.43/kWh up to ~1100kW/month.
After that every kWh is $.48-$.50/kWh.
Now, with both systems running, I’ve saved over $100/month on average (2018: $1300, 2017: $1500).
Having residential solar is a money losing endeavor. For me and a heck of a lot of others who have gone that route.
I noticed you provided no details on your financial costs for going solar.
The fact that you state that you save $100/month on average without stating what the financial costs for going solar were means that your savings data is flawed and useless.
Friendly feedback: You could have phrased that as: “Can you provide details on your financial costs for going solar? It’s hard to tell if we’re comparing apples to apples on that $100/month, and I’m skeptical.” instead of the verbal jabs.
I provided all the necessary info, actually. By their very nature, PPAs have no up front cost. I also mentioned what I’ve saved in the 2 full years since moving to 2 solar systems, which averaged across 12 months, is a little over $100/month.
I have a spreadsheet where I’ve tracked the power provided by solar, the cost of said power, power from the utility and what it cost. This is also used to calculate what I would have spent based on the published monthly kWh tier allotments and the price at each tier.
Last year I paid ~$30 at the end of the net metering year for the pleasure of being connected to the utility, while paying ~$1700 for PPA power. The spreadsheet, for the full year, said I would have spent just about $3000 on power solely from the utility.
Again, congratulations for having access to cheap power that makes solar uneconomical. Not all of us are so lucky.
This is so cool. I’ve daydreamed about a solar house in the past, but we’ve got two really big trees in the back yard, which faces west. They keep the temperatures down in the summer and provide a nice wind block in the winter. I’d hate to give those up.
Do you use electricity for both heating and cooling? 25 MWh seems like a lot.
Our electricity usage is 5 MWh yearly for two people. Cooking and heating are gas-based, no need for cooling (in the Netherlands, Europe).
Cooling is electric, but our furnace, stove, and dryer are gas. From December to March, we averaged around 33 kWh per day. Now that the furnace is off, we’re down to around 22 or so. That includes me being a full-time telecommuter. There’s always lights and PCs on during the day. Over the last two weeks, the only times we’ve broken 25 were two days where the furnace ran because the high was in the 50-55 F range.
Ameren just replaced our electric meter, and so now we get much more immediate and granular information on their website. It’s fun to look at.
edit: electricity is cheap here. We’re paying 5.75 cents per kWh. For the first 800 kWh, we pay a 3-cent distribution fee bringing the total up to 8.75 cents. After 800 kWh the distribution fee drops to 1.6 cents, for a total just over 7. IT goes up during the summer, though, and we use a lot more power in the summer. Last July was 1500 kWh. So we do “budget billing” where we pay the same each month and then settle up at the end of the 12-month cycle. Every year, Ameren credits me around $40 to make up the difference.
Total electric charges for 833 kWh on my last bill were $93 including the meter and taxes. Gas was around $60 for 70 therms. I gave Ameren $172 so that I don’t have to pay a $300 bill in the summer.
It looks like we use around 7 to 8 MWh per year, if I did that addition correctly. 😆
These sorts of long-term, house-related projects tend to [financially] fail miserably, at least around here — I’m in the Toronto area.
I bought my first house about 8 years ago. Buy a hot water tank, or rent one. I did the math. Buying one would break even after 9 years, basically feeding me $40/month thereafter. Tanks last 15-to-20 years, so it was well worth it, on paper.
As luck would have it, my friend also bought a house that same year. His already had a fully-owned hot water tank. It was already 9 years old. It was perfectly good. But his homeowner’s insurance said that they wouldn’t cover him for water damage with a ten-year old tank.
That was it for the math right there. House insurance beats out 10-year investments in $4’000 pay-outs.
My neighbours across the street have a south-facing solar array on their roof. There are at least a dozen pigeons living in the very small space underneath it. Good thing they have a plastic owl standing guard to scare away the sparrows. I don’t know what it costs to clean the bio hazard waste that is pigeon-poop, nor the endless bird sounds of chirping, scratching, and cooing that must go on under there. But I can guess what it costs to replace the roof after the birds have pecked through it into the attic.
Ten years is a very long time for mystery problems to appear. Unexpected, unknown, as-of-yet-non-existent issues creep up fast and change everything.
That’s why math sucks; it’s never complete.
A damaged panel, replacement hardware, it all adds up. But what about the end of net-metering after 5 years? Or next year? What if a few DIY rooves collapse so your homeowners insurance stops covering any solar rooves?
And what if, much more simply, insurance doesn’t cover your solar array? At the very least, $65’000 value, grows your premiums a bit doesn’t it?
A hail storm. A wind storm. Teenagers.
For me, these sorts of I-can-do-it-cheaper need a pay-out within 3-to-5 years. Beyond that, there are simply too many opportunities for things to go terribly wrong.
Similarly I would advise people to never have kids and never fall in love. So much can go terribly wrong.
Getting out of bed in the morning is perilous. You could slip on a sock, fall, break your nose. Just not worth getting up.
And that’s why we pay a lot of money to insure against those very things. Doing so gives us the freedom to take those risks as a matter of routine. We drive cars that cost more than we can save in three years of discretionary income, purely because we don’t worry about damaging to it nor to us.
But to your point, how much money would you put down as a bet that you won’t break a bone (slipping on a sock, or onto your nose) over the course of the next 10 years?
Personally, I’d probably be willing to bet $2’000 that I won’t break a bone in the next 3-5 years. But I wouldn’t bet $65’000 that I won’t break a bone in the next 12-14 years.
You have kids planning to spend money, not save it, and planning to have more problems, not fewer. You don’t have children as an investment in elderly care.
As for falling in love, we’re long past the days (here at least) of falling in love as an investment in having your needs met. Instead, we fall in love to have company through tragic times. It’s never cheaper, it’s never more freedom, and it’s rarely (in terms of days per year) better. But it remains very much worthwhile at the extremes (both good events and tragic ones).
[i<]blink[/i<] Keep your chin up. Love may be hard to find, but it's definitely worthwhile when you do. Sure, there are a few downsides, but the positives far far outweigh the cons.
At least falling in love has upsides. Kids? Ehhhhh..
Do you mean MGTOW? I agree.
Hence why I started the story how I did. Those are risks I’m willing to take.
It’s funny how you start the story with the disclaimer that you know the whole thing isn’t the best investment you can make from a mathematical perspective and then in the comments everyone piles on about how it’s not a great investment from a mathematical perspective.
Welcome to the Internet, you must be new here. 😉
That’s not fair. One paragraph about dreams, followed by five pages about math. You’re shocked that there’s feedback about the math?
But it’s more than that.
Your dream (as I understand it) was never to build it, and then promptly have it destroyed. Your dream wasn’t to have it for a year, and then move away.
Your dream (again, as I understand it) was to have it persist for a significant portion of your life, and even for your daughters’ lives.
If, as a result of some failure, it vanishes in 3 years, then that sucks. It has nothing to do with the financial benefits (which aren’t your objective) but it does have everything to do with the financial pitfalls — which can ultimately force you to destroy it.
As a truly sucky example, if a storm destroys $35’000 of your work, and it isn’t affordable enough to rebuild, then you won’t rebuild it.
Oh, I’m not shocked. I should have explained a couple things better, though. Namely that really bad things will be covered by homeowners insurance and that slightly less bad things will be covered by the 10-25 year warranty on the various parts of the system.
If that homeowner can’t be troubled to scare the birds by washing the nests out in early spring around the same time when they clean the gutters, then they’ve probably made peace with the upstairs neighbors.
As for the other, pigeons aren’t woodpeckers. The acidity in their poop will certainly degrade the roof at an accelerated rate, but that goes back to the evident unwillingness to chase the pigeons out periodically.
Oh, hey, if we’re spending $65’000, and are willing to handle more work as a result, then that’s very peaceful. But as usual, if I were willing to work another hundred hours a year on home projects and bird shooing, I’m sure those 100 hours could be put to lots of things that give me more joy than electricity.
Bullshit pigeons don’t peck, and scratch. By the way, woodpeckers peck to create sound and eat bugs, not to dig out wood. But none of this matters. Birds build their homes. If their home is five inches between panels and shingles, I promise you they’ll add another inch over the course of a decade. We’re talking about tens of thousands of dollars of roof. Damage is significant for lots of reasons.
Every action we take is a gamble, anything can go wrong at any time…. doesn’t mean stop breathing because you might have a pulmonary embolism.
The uncertainty of life does not mean that all actions have equally unknowable outcomes.
You make good points. There are a few additional advantages to having solar: 1. You are doing something (probably) good for the planet 2. Cool gadgets 3. Synergy with electric car: will conveniently store energy when surplus is produced, thus being practically free to use, if your power budget is sufficient
For all the reasons that you mention, I wouldn’t advise this as an investment for people who are short on cash or need to first deal with other priorities. But if you have a decent income, live in a sunny area and do this the right way there is a very good chance that long term you will make money.
I have to agree that a lot can happen in 10 years.
I have some inlaws with what looks to be a similarly large solar installation, they had some major component (an inverter?) fail out of warranty, I don’t know the specifics. The replacement cost was considerable however. Wish I could remember what it cost them, but I’m thinking it will have added some years to the payback on the system. There is a good chance they shot themselves in the foot buying too cheaply.
[quote=”drfish”<]The same lack of shade that makes my house good for solar also makes it a bear to keep cool. [/quote<] Now that the panels are on the roof, covering a large majority of it and providing a small air gap between where the sunshine is hitting and the roof materials, do you know if that will provide any reduction of heat absorption in the roof? IE, make it slightly cheaper to cool during the summer? And conversely, making it slightly more expensive to heat in the winter?
That’s a popular question, and one I will definitely try to quantify in a follow-up piece. It sounds good in theory.
Right on. Also thanks for this article, I’ve definitely been thinking about solar on our next house and this is a really good write up on a complete system with battery.
I’ve wondered about this also. My business is in a metal condo and the AC cooling of it in peak summer runs between $650/mo to $850/mo during the summer.
The idea of cooling the panels for summer and conversely at need warming them enough to melt snow in winter is interesting. But it must be weighed against the net improvement in performance during both seasons. The summer cooling seems like a win if you need the hot water. In the southwest it gets cool at night and I knew one guy that used it to heat their swimming pool, summer and winter. Winter sunlight is quite a bit less effective for generation because of solar angle so is it worth it to use energy to clear the snow? I guess that would depend on how often snow events happen.
Solar panels usually get pretty hot because they’re trying to capture as much light as possible and convert it to electricity. The efficiency of the process is fairly low and as I understand it, solar panels get hotter than shingles.
One of my old coworkers actually created a startup based around the idea of piping water through the panels. The idea is that you need to heat up water anyway and you want to cool the panels anyway, so why not take the excess heat that you don’t want from the solar panels to become the heat you do want in your hot water tank.
That is an excellent thought. Up in the Adirondacks is a cool museum [url<]https://www.wildcenter.org[/url<] Where they have a solar heat transfer system with evacuated chambers to convert solar to hot water very efficiently even when it is very cold outside. Poke around on the website and I'm sure you can find more information. You could probably Gerry-rig something yourself using the same materials as used for sub-floor heating and heat-exchangers, if only to pre-warm water before it enters your water heater.
There was a time when “solar” meant exactly that, i.e. using the sun to heat a liquid heat transfer media. Used to see lots of those on roofs in the ’70s/’80s.
A lot of gunked-up plumbing and rotted roofs as a result, which is why you don’t see many of them now. The materials science of that day wasn’t quite up to the task.
I imagine that a modern stainless steel system with appropriate silicone tubing would work a fair bit better but the plumbing is still more of a wildcard to install and maintain than the electrical wiring.
It’s been popular in some countries since the 60s, maybe 50s: [url<]https://en.wikipedia.org/wiki/Solar_water_heating[/url<]
This article is so awesome! Makes me want to take the leap!
Thanks for documenting your experience. I grew up in Michigan, but now live in Dallas and have always been curious about solar roofing. I’m curious about your electricity costs though. It’s only my wife and I in our house, but my electricity bill rarely goes north of $200 even running the AC from 100+ outside to 72 inside.
Here in Dallas, we have the issue of hail damage. You have what seems like a one-in-twenty chance of having roof damage from hail in any given year (maybe even worse than that). Still, Dallas does get a lot more sun than Michigan and we don’t have to deal with the snow problem. My roof is only 3-4 years old, but if I were looking to replace it, I would definitely consider solar roofing. There’s already a few folks in my neighborhood that have it.
While solar roofing is not yet cost effective, I can’t help but wonder if some of the cost could be recaptured in the increased value of the home. For example, I install a solar roof for $50,000 on my house and live in the house for the next 10 years. When I sell the house, how much of that $50,000 will my solar panels add to the selling price? With this consideration, it may be easier to justify the large upfront cost.
We got our PMI removed from our mortgage payment shortly after the panels went up. The value of our home had gone up enough without the panels that it we could have gotten it removed regardless, but what was interesting is that there was a cap on the value the appraiser could use for a solar panel system, just $28k.
the better question might be, what is the lifespan of current tech panels/ whole system? and the associated warranty.
Essentially, I’m covered for 25 years and hoping for 35. The battery is covered for 10 years, with an LG-specific warranty on the capacity of the cells, which is nice.
25 Years…..That’s a pretty darn good lifespan. I’d assume as wear and tear set in you’d be replacing what is needed al carte.
What does the panel maker say about hail resistance?
The panels are not warrantied for hail damage, but my home insurance covers it.
If hail damage happens a few years down the road when the panels start losing efficiency, it might actually benefit you if they break 🙂
Only a net benefit if hail is extremely rare where you live. My state, Colorado, is second only to Texas for major hail events (thanks, Rocky Mountains!). Three of this state’s top-ten costliest storms took place between 2016-2018. The effect of that on homeowner and automotive insurance premiums has been almost as catastrophic as the storms.
So yeah, your stuff will get repaired/replaced, but you’ll still pay for it in the long run.
Yeah, that’s basically how insurance works. It’s spreading the cost of negative events across everyone buying insurance for that kind of thing… while letting the middle man make a nice profit.
Thoroughly enjoyed this read. Once the zombies come, I’ll have to put on my full-kevlar motorcycle outfit (so their bites can’t get through) and somehow make my way across the lake to help set up TR resistance headquarters.
You shouldn’t have to worry too much in the winter (they don’t have any body heat, so they’ll freeze solid), but I’m wondering if something like a leaf-blower on a pole could clear light, powdery snow?
Believe it or not, a rail-mounted leaf blower is on my list of crazy ideas to give further consideration too. I have to be careful not to do anything to clear off the panels thay may void the warranty though. Hence the plan of just having so much that it doesn’t even matter if they are covered for 1/4 of the year.
As someone who doesn’t really care about gardening, are there any real disadvantages to putting a large array at ground level – say on a permanent scaffold about 2′ off the floor?
I’d imagine they’d be easier to maintain/clean if they weren’t on a roof and it’d make roofing maintenance a lot less hassle.
There’s a cost associated with building a framework for ground-mounted panels that is less for roof-mounted ones. Also, shade is a bigger problem because the house itself will block the panels in many locations.
My roof is new enough that it should last as long as the panels and, by all accounts, the section of the roof under the panels (most of it in my case) won’t see much wear because the panels are protecting it.
Actually that is far preferable in most cases, and what I plan to do. Installation costs less, it can be more easily maintained, and you don’t have to get on the roof. The drawback is if you have a long run between the array and the house, the copper can be pricey.
Something to seriously consider is protection from hail. On ground level, you can quickly drape some protection over it. On a roof? Much more difficult.
No plan here to spend $65K on a system, but I am sure a big chunk of costs is the battery backup and its integration into the system. I am afraid to spend money on one of those for fear of needing to replace that far more often than anything else in the system. In order to get NY incentives, I must be connected to the grid also.
My other problem is my electric bill averages about $175 in a 2500sq ft house. We only run AC in the bedrooms, and heat with wood/propane. Our ROI is going to take a while to pull off.
![20 kW solar system: Full Installation Walk-Through](http://cdn.globalso.com/bicodi/31.jpg)
550w Solar Panel This is on the TODO list if my wife ever lands a job again. Having a little trouble in that department.