SOLAR POWER

post your experiences with it

ie: i have a 1 inch solar car or my house is solar

or news

http://www.treehugger.com/renewable-energy/walmart-more-solar-power--capacity-38-us-states.html

I have a solar powered wireless keyboard, which is pretty cool I think

I was always told that if your roof doesn't face south then in cloudy N. European climates they are mostly useless.

I was just reading they should face west - at least if you get billed for peak use

http://www.evoenergy.co.uk/wp-content/uploads/home-suitability_orientation_Aug20123-320x239.jpg

A perfect roof for solar PV would be large, south facing and pitched at an angle between 30º and 45º

http://thinkprogress.org/climate/2014/04/30/3432172/arizona-solar-property-tax/

yes let's make it more unattractive to use clean renewable energy source

Some time circa 1980 I bought a Casio solar-powered calculator for about $8. It still works. I still use it.

http://thinkprogress.org/climate/2014/04/30/3432172/arizona-solar-property-tax/

these fucking ALEC people... it's gratifying that they've been failing for the most part but just grrr

I am also dismayed at the net metering battles

http://www.solarcity.com/learn/understanding-netmetering.aspx

climate change = the need to help clean energy grow , not treat it like any other business

oh hi, this is my field

ALEC sucks

most people feel that the subsidies are hindering the industry in the long run, it needs to go toe to toe with fossil - since the modules are dirt cheap, the barriers esp. in America are permitting costs & red tape.

more later maybe

I live in Southern California with a clear south facing roof. A guy came by one day to run the numbers on a solar panel system lease. He was really excited about the roof and said it would be a big savings. It turns out I would have been guaranteed to save $35/month which wasn't very exciting to me - especially since it was a 20 year lease/commitment. I just kept thinking that in even 10 years, these panels will probably cost nothing.

I also wonder why there aren't more living people wearing solar watches on 'The Walking Dead'.

the solar lease thing was attractive to me for a little bit but now I'm thinking that's basically lining the pockets of a bank somewhere.

xp
Ditto for me (SoCal south-facing roof) but my electric bill isn't that high. If I ever break down and get A/C, or a plug-in electric car, I'd do it.

u guys ya gotta take the rebates into account - payback time on a 5 KW system in CA right now is just over 6 years

(I really am busy, but had to note that)

solarpowerrocks dot com has a good rundown of rebates & incentives

That included the rebates/incentives etc etc, which were all rolled into the lease. This was about a year and a half ago. He recently came by having quit the (leading) lease company and was selling systems outright and the savings would have been similar but with a much shorter loan commitment.

He's annoyed that i won't sign up for guaranteed savings, but I just feel like it will get cheaper and cheaper so why commit now?

A perfect roof for solar PV would be large, south facing and pitched at an angle between 30º and 45º
― under the cobblestones, le dogshit (xelab), Saturday, 3 May 2014 03:04 (3 days ago) Bookmark Flag Post Permalink

Not necessarily so, it depends whether you want to maximise your grid exports or minimise your grid consumption. A decision you have to make base don the relative value of the feed in tariff versus retail electricity price. Although south* facing panels (angled appropriately) maximises electricity production. East and west facing panels match typical domestic loads (morning and evening) . Given that panels are so cheap right now a better array would be oversized, relative to the inverter, and cover all three aspects.

*Flip south for north for my hemisphere

Panels and inverters are getting cheaper, but as they become a smaller proportion of total system cost, the effect to total system cost will be lessened so there will be a levelling off of prices. US has very high installation costs relative to Germany and especially Australia. Solar systems cost a lot more because of these 'soft' costs. There's obviously room for improvement there as both Australia and Germany are high wage economies, but soft costs will be hard to reduce.

http://www.nrel.gov/news/press/2013/5306.html

If you should lock in a good FiT then you should go for it because the premium FiT backlash in Australia was savage and quick when it happened.

Solar is cost competitive with grid power in the absence of subsides in Australia although this is partly due to ridiculously high electricity prices, inflated by over investing in the electricity grid (also population density, cross subsides etc. etc.)

grid parity!! see also: Hawaii

Ed totally otm, of course

yeah yolu don't get the rebates under the lease plans. the company installing does, and 'passes that savings on to you' if you believe that.

lol don't get me started abt leasing, what a scam

see here (I don't know these people but the video is good)

http://vimeo.com/70888784

I think electrical rates will increase in thte future but solar will be cheaper - thus they have an incentive to fight people getting solar - just like the oil industry woudl fight if people could harevst and refine gasoline from their backyards.

I am getting heat pumps heater and domwestic hot water and I hope to in the future have them powered by solar

http://www.pressherald.com/news/Net-zero_energy_homes_a_building_trend_.html

envious

The next cool thing will be putting your hetapump or watever on the DC bus. 80% of what you have in your home runs on DC and solar panels produce DC. DC to DC conversion is much more efficient than DC-AC-DC. Some of the AC-DC conversion is criminally inefficient <50% doesn't get wasted.

Are you doing solar thermal for your hot water as well? Solar thermal with an electric/gas boost is very popular down here, probably the best playback for solar, plus you get storage.

NO to solar for hot water, not really a good roofspace for it right now (trees)

so you could have yoru whole house on DC if you just ran it all from solar panels? WHat abotu connection to the grid? have yoru house get inverted to dc from the street?

Pretty much, although it would be a bit heath robinson at the moment. The infrastructure in terms of plugs and sockets, DC-DC converters isn't there yet but its coming. Most of the DC focus has been in data centres at 380V and commercial lighting at 48V but 3 wire 120V DC would be pretty effective in the home.

You'd have to invert/rectify for a 2 way grid connection but that would be more efficient than all the little wall warts you currently have.

lotta new construction has 5 VDC built in, it's funny because aiui USB was never intended as a power delivery source, just data.

as Ed says, DC appliances for the home are coming soon/already here - some DC fridges are on the market now.

we'll probably still see long distance grid transmission in AC, but more and more DC at a local level - see also all the discussion around microgrids, once again folks in developing countries can leapfrog technology like they did w/cell phone infrastructure and have localized power grids.

I think you'd still have to have batteries or some other form of energy storage (flywheel etc, I have seen all kinds of zany ideas) to use solar-generated DC effectively in a home DC environment. That storage seems like the weak link in all of this right now, although lithium ion has promise it is very expensive.

this summer I am gonna put a small 300-400 watt kit together to run our chest freezer and whatever else I can throw on the inverter without hitting 50% depth of discharge on the batteries. I'll probably use MK Deka AGM type, my understanding is that they're good for 5-7 years depending on how hard you cycle them.

Deka, Trojan, Sonnenschien seem to be the brands that people talk about the most as far as storage goes right now. What brand of BMS/Charge controller are you going to use?

well Outback would be my top choice, and Morningstar my second. Since the Outbacks are around $500, I think I'll probably use an MPPT Morningstar with a 45 amp limit (maybe $350?)- both those brands have high input voltage limits so you can stack the panels in series to reduce voltage drop. If my budget can't handle it, I'll put the panels in parallel, use a Xantrex C35, and upgrade later.

feasibility of generating wind power? I mean you would have to have a really windy location I would think to get any juice

Xantrex really is the best I can think of where solar +storage are concerned. I was at a solar trade fair last week and a local integrator that has previously been all about Xantrex was repping for a Chinese brand called Solax, although when questioned they hadn't installed many.

Outback and Midnite are very popular with the Northern California Weed growing crowd.

Wind, wind isn't particularly economical at small scale, the turbines are OK but you then have to build a sacking great tower to get it to a height that will lift it out of the wind shadow of trees and other structures. Permitting for a decent size wind tower is going to be way, way harder than solar.

what aboout many many littel windmills?
they woudl be cute anyway

My concern is how to store power generated from solar in the summertime that is excess from what you need, so you can use it later in winter months. Some kind of huge batteries? would the power stay for months?
somehow convert the power to a fuel?

omfg let us ridicule these scum (C & P'd from National Report so as not to give them clicks)

<National Report>This week, a scientific research facility in Wyoming made a startling discovery that is certain to change the way millions of Americans look at the environmentalism movement, after they found conclusive evidence that solar panels not only convert the sun’s energy into usable energy, but that they are also draining the sun of its own energy, possibly with catastrophic consequences far worse than global warming.
Scientists at the Wyoming Institute of Technology, a privately-owned think tank located in Cheyenne, Wyoming, discovered that energy radiated from the sun isn’t merely captured in solar panels, but that energy is directly physically drawn from the sun by those panels, in a process they refer to as “forced photovoltaic drainage.”
“Put into laymen’s terms, the solar panels capture the sun’s energy, but pull on the sun over time, forcing more energy to be released than the sun is actually producing,” WIT claims in a scientific white paper published on Wednesday. “Imagine a waterfall, dumping water. But you aren’t catching the water in buckets, but rather sucking it in with a vacuum cleaner. Eventually, you’re going to suck in so much water that you drain the river above that waterfall completely.”

WIT is adamant that there’s no immediate danger, however. “Currently, solar panels are an energy niche, and do not pose a serious risk to the sun. But if we converted our grids to solar energy in a big way, with panels on domestic homes and commercial businesses, and paving our parking lots with panels, we’d start seeing very serious problems over time. If every home in the world had solar panels on their roofs, global temperatures would drop by as much as thirty degrees over twenty years, and the sun could die out within three hundred to four hundred years.”
The study was commissioned in August 2011 by the Halliburton corporation, who wanted to learn if the energy giant should start manufacturing and selling solar panels domestically and internationally. Halliburton’s executives wanted to know more about the sustainability of solar energy and how photovoltaic technology might evolve over the next ten years. But based on the findings of WIT’s research in the field, Halliburton revealed on Friday that they will not be entering the solar energy market.
“Solar panels destroying the sun could potentially be the worst man-made climate disaster in the history of the world, and Halliburton will not be taking part in that,” the company stated in a press release issued Friday morning. “It’s obvious, based on the findings of this neutral scientific research group, that humans needs to become more dependent on fossil fuels like oil and coal, not less. Because these so-called `green technologies’ are far more dangerous to the Earth than any hydrofracking operation or deep-water drilling station. What good is clean air when our very sun is no longer functional?”
- See more at: http://nationalreport.net/solar-panels-drain-suns-energy-experts-say/#sthash.w1rwE6tn.dpuf

oh n/m it's a parody site

http://www.thermodynamicpanelsuk.com/

anyone knwo much abotu this

solar leasing vs. owning - which is the better?

even w/o my knowledge of the industry, as a homeowner I'd never lease:

http://www.pv-tech.org/guest_blog/the_true_costs_of_solar_leasing

leases don't make sense for residences afaik

Solar Tariffs Seem Certain To Hurt U.S. Installation Market

http://www.revisionenergy.com/maine-nh-solar-financing-loans.php

thinking of doing this

Does anyone have any thoughts about solar roadways?

(Is there a separate thread where it's being discussed?)

fuckin Nevada, it blows my mind

thanks to WmC for the link

http://www.vox.com/2016/1/20/10793732/nevada-solar-industry-explained

not sure what can be done at this point, the brazen bait-and-switch move here is just insane

yeah this is ridiculous and will bite them in the ass

they're not the only states where investor-owned utilities are trying to roll back net-energy-metering - distributed generation systems are basically a death knell for the traditional utility distribution system model

awful

but no fear, the Republican Party is almost dead

PUC is caving on the retroactive issue, hopefully:

https://www.greentechmedia.com/articles/read/nevada-puc-to-reconsider-grandfathering-rooftop-solar-customers-into-new-ne

there's no way this entire debacle doesn't get reversed at some pt imo - either because of lawsuits or political pressure

boo

I haven't posted or even been on ILX for a long time but this seems like a good time to decloak.

Naturally net-metering is important but providing parity payment is unsustainable and although the way it was handled in Nevada was utterly boneheaded it probably had to go in time. My understanding was that NV provided no-sunset for parity net metering payments and rather than closing the scheme for new installs pulled the rug from under existing owners. In a market with so many PPAs and people having bought into sola under assumptions of payback over time that was plain wrong.

Over here in Australia we've had all kinds of incentive scheme from Carbo based credits, generous (66c/kWh) and less generous gross metering, and net metering. Currently every new customer gets the carbon credit (Renewable Energy Target) up front and a net metering create of ~5c/kWh for the avoided wholesale cost of electricity. There is no credit for the avoided transmission and distribution costs and the benefit that that solar offers the network is not compensated for - that said the extra costs that solar customers (and those with big A/Cs and pools) impose not he network are not fairly distributed either.

All of this is leading to much more generous pricing and compensation models. We've had a regulatory process (called Power of Choice) which is leading to more cost reflective network pricing (Residential Demand Charges and or Time of Use) which will penalise A/C use and reduce the self-consumption benefit of solar (without storage). Further off It something I've been working on if the Local Generation Network Credit which is a proposed mechanism for compensating distributed generator owners for the value they do offer the network. It will go some way to recognise that solar on a residential zone sub at 2pm is not very useful but at 4pm it is very useful. There's a good description of the way it works in other jurisdictions in the briefing paper for one of the workshops I've been involved in.

https://www.uts.edu.au/sites/default/files/LNCVNM_towards_an_LNC_methodology.pdf

The TL;DR on this: this shit is complicated

thanks, gonna dig into that when I have time.

I am sympathetic to the "costs of distribution" argument in terms of reforming net metering, but as you note the retroactive penalty was where the PUC really fucked up in NV.

CA PUC smarter than NV PUC:

http://www.sfgate.com/business/article/Solar-companies-and-customers-win-big-in-6790872.php

great news

congress looking into some pre-emptive legislation forbidding retroactive net metering changes:

http://www.pv-magazine.com/news/details/beitrag/us-senators-move-to-preserve-solar-net-metering-through-energy-bill-amendment_100023050/#axzz3z6VXCpq9

Hope that passes, good on them. Murkowski being in charge is of course disgusting and counterproductive.

Ah but when everyone has a telsa powerwall the grid will no longer be of any concern!

incorrect, those batteries don't store enough power to run a house, the stored power is used for peak shaving and load reduction

they also quietly discontinued the larger model last week:

http://www.greentechmedia.com/articles/read/Tesla-Discontinues-10kWh-Powerwall-Home-Battery

cuz guess what? they are just too expensive.

sad lol

someone really needs to crack this battery storage issue

i'm probably going to do a solar lease. I know this doesn't give me the tax benefits purchase would do, but I already owe the IRS money so on a monthly basis leasing saves me more. I'm guessing that CA already worked out the issues that are plaguing NV and ruining the industry for them over there.

recent CA PUC ruling preserving net metering is posted upthread

oddly I JUST NOW got a CREDO email saying that they are challenging that. Fuckers.

http://www.sandiegouniontribune.com/news/2016/mar/08/utilities-net-metering-decision/

so not gonna happen

good range of comments on that article

Galatians! lol

the key is to convert solar power to heated magma to be used later!

https://www.theatlantic.com/science/archive/2016/12/the-solar-industry-has-paid-off-its-carbon-debts/510308/

Well that's neat

more trade war details for anyone who is interested

https://www.greentechmedia.com/articles/read/suniva-solarworld-file-new-trade-remedy-proposals#gs.96pEz6E

as I mentioned in the Global Warming thread, one of the big problems with all of this is that four years isn't a long enough window to actually build cell factories if the tariffs that make them cost-effective disappear after that point.

Circa 1980 I bought a Casio solar-powered calculator, just the kind that does basic arithmetic operations. It has only just now bit the dust, after providing me with 37 years of faithful service and not a single battery required, let alone daily recharging. It was perfection of its kind. Of course, with mobile phones now performing the same functions, I will never be able to replace it.

Ha! I have such a Casio, bought at about the same time, and it's still working fine.

Mine was dropped once too often.

waiting for the penny to drop on Monday w/r/t tariffs or cell quotas

this speech does not bode well:

http://www.smh.com.au/world/us-will-no-longer-be-taken-advantage-of-on-trade-trumps-sharp-rebuke-to-china-20171110-gzj60v.html

idk that reads like his usual empty bluster

and nothing specific about the solar tariff issue

I know, I'm just paranoid.

The ITC recommended like four different options, nobody has any idea what's going to happen and it's the uncertainty that's wearing on me

60 more days of misery, uncertainly, market disruption, and fear. This is the worst.

https://pv-magazine-usa.com/2017/11/13/the-clock-ticks-itc-turns-section-201-over-to-president-trump/

pv magazine staff has found no sources that can tell us more about this confidential report, and ITC staff has stated that a public version will be released at an unspecified later date. {...}

In other words, President Trump can do just about anything. There are precious few limitations, but these include that initial trade action can last four years (and be extended to up to eight years), and that tariffs are limited to 50% of the price of products “above the rate existing before the proclamation of action”.

This last detail may be more complex than it first appears. While all the commissioners who recommended import duties would have the tariff values calculated on the cost when solar products enter the nation, SolarWorld and Suniva have asked for duties equal to 50% of the prices during timeframes covering previous years when solar cells and modules were much more expensive.

Neither SolarWorld nor Suniva has done much to mitigate these proposals, which we at pv magazine feel are dangerous and unreasonable.

"uncertainty"

dumbfucks

both of those companies can burn in hell, forever

so selfish and stupid

yeah it's rather remarkable

Other solar groups have stepped up to support the cause using social and advertising campaigns. A coalition of manufacturers, U.S. Made Solar, has been running TV advertisements during shows that President Trump watches regularly, such as Fox & Friends.

https://www.greentechmedia.com/articles/read/solar-industry-makes-last-ditch-lobbying-against-solar-tariffs#gs.rMpfhZI

we'll know within two weeks, probably. good article.

30% tariff, could have been worse, hopefully Solar World and Suniva die now

https://www.greentechmedia.com/articles/read/breaking-trump-admin-issues-a-30-solar-tariff#gs.8mgzsVs

well looks like Solar World found a way out

https://www.greentechmedia.com/articles/read/sunpower-acquires-solarworld-americas#gs.E0HOHd0

Anyone here have experience getting solar at home? I've been intrigued for years, but the numbers seem completely unappetizing. When I put our address into the supposedly close to accurate free google solar calculator, for example (https://www.google.com/get/sunroof), it claims savings of $6000 over *20 years*. $300 a year for two decades seems a pretty paltry reward for putting five-figures into the system, even with (dwindling) tax write-offs and rebates. And yeah, floating somewhere in there is environmental impact, but on that front it seems much more efficient/easy to just find ways to use less power, or if you're feeling generous just donating that huge amount of upfront install cost to a food pantry or something, where every dollar given gets exponential returns.

I dunno. Am I looking at this all wrong?

(caveats: i don't own a home, and i haven't payed close attention to this stuff for a while)

i think you're generally looking at it in a reasonable way. a couple thoughts:

- solar panels are getting less expensive and are a lot cheaper than they used to be, but they still typically have long payback periods (the amount of time it takes to recoup the upfront cost) for individual homeowners.
- some utilities have amazing financing programs where they'll pay quite a bit of the upfront costs and gradually bill it to you on your utility statement every month. some don't.
- in general, solar is much more economical at scale. at some point if we don't have the dumbest person of all time as our president, maybe we'll upgrade our grid and energy policies so that individual homeowners with solar can even feed excess energy INTO the grid and make a little money. but instead we live in this world.
- you're spot on, i think, about looking for other ways to use less power and using that money for something else right now. you can get a free home energy audit (disclosure: i work in this field) from your utility that will identify energy saving measures, and in a lot of cases the utility will even install free equipment (smart thermostats, energy-saving aerators for faucets, etc). energy efficiency measures typically have a MUCH shorter payback period than solar panels on a roof.

oops, my link was broken. i meant to link to an image of concentrated solar power:

https://news.energysage.com/wp-content/uploads/2018/11/11.14.18_solar.jpg

curious to hear from people from other non-chicago places though! like i said, i haven't followed it closely in a while and it's possible that people in warm sunny progressive places are able to take advantage of residential solar in a more cost-efficient manner

final, contradictory, thought - if you're planning on staying in your house for 15 to 20 years (long enough to cover the payback period and start recouping costs) and have extra money, you should still consider it!
just know that in 5 years there will be better, cheaper solar and your neighbors will be putting it on their roofs and recouping their costs in 8 years instead of 15 (or whatever). the price of solar is likely to keep dropping, so the longer you wait, the better the deal. i'm sure there are people who put solar on their roofs 10 years ago that are insanely jealous of the current tech and prices.

final final thought: i don't think IL has a state tax credit for residential solar right now. if it were me and i had a home and some money, i'd wait until we get a state tax credit, in addition to the federal incentives.

Yeah, thanks for all that. We have a relatively new home, so everything is running pretty efficiently. Our total power bill last year was $1100, which ... doesn't seem that high. Now, if solar could take *$600* off the bill annually ... that would still be kinda low for the investment, since it's not even a sure thing we'll even be in this house for another 15-20 years; incredibly, we're (likely) empty nesters in about six!

I have three friends that have gotten or are about to get solar, and the stories/numbers/savings they cite just don't jibe with my (casual) research. I, too, would love to hear stories from places that are not Chicagoland, though.

detailed breakdowns for IL available here:

https://www.solarpowerrocks.com/illinois/

8-year payback period and 15.73% IRR on average

a lot of those saving are due to the 26% tax credit - do you have a tax burden? that's where the real savings are with this.

Thanks. It looks like the tax credit expires after 2021, and President Asshole could just order it ended tomorrow, couldn't he? Either way, in theory I'd get a 26% tax rebate for 2020, then 21% in 2021, then nothing after that. But if that website is more or less accurate, and the avg. savings is more or less what I pay in power annually, then yeah, 8 (or maybe 10) year payback seems possible. We have a consult with someone tomorrow, I'm curious what they say.

no the tax credit is 26% if you get it installed in 2020 - then, if the credit is more than your tax burden, you can spread the credit out over an up-to-five-year period. but it's a one-time credit, 26% of your total cost *including* installation.

the difference in payback times between states is based entirely on state or utility-based incentives, so if you have time dig in to the state incentives on that page.

According to that site it looks like IL offers no rebates or tax incentives.

ah yeah looks like the incentives ran out (that happens frequently)

this might help:

There is still hope for residents of Springfield and Chicago, which each have their own solar grant programs. Your installer (click here to see what you can save with solar power on your home) will give you all the details on those and any other grants and rebates you may qualify for.

for what it's worth I'm a big fan of the SMA inverters that have an optional outlet you can install that provides 15-amp 120V power during the day if there is a power outage

SMA is so bloody expensive though. Buy Chinese either Ginlong or Sungrow. I’ve visited both their factories and their quality systems are great. I commissioned a full quality audit on Ginlong a few years back and they rated really highly and I only ever had one quality issue in dealing with them over 1000s of installs. (a weird clipping issue at maximum output that got solved in subsequent models)

If you have a difficult roof or shading issues, get SolarEdge.

I agree with Ed, Sungrow is good as well and SolarEdge is the best choice for shaded roofs - SMA won't work well with shade

I just *really* like the Secure Power Supply feature on SMA

also, Ed I would love to hear the gory details about that clipping issue if you are so inclined

We've got an ideal house and roof for a lot of this, so we'll see what the guy says tomorrow.

Just got off the phone with a good friend of mine who deals with these issues on a regular basis, and he is dubious about solar. Very bullish on geothermal though, because it's a constant. There's nothing to generate, no changing costs or production. It just does this thing. Vs. solar, which is beholden to myriad other factors.

He also, as Karl noted above, stressed the importance of simple shit, like insulation, to making sure your home is as efficient as possible. Doesn't matter where your power or heat or cooling is coming from if you lose half of it through your walls and windows.

Quick question: if I'm about to talk to this guy about solar, what specific questions do you think I should I ask him? What answers would be most useful for someone on the fence?

estimated payback time

price difference for different inverter options as Ed noted (Sungrow, Solar Edge, SMA if you want to spend a bit more for a backup outlet)

I dunno, what are your on-the-fence concerns? Like for example, this:

There's nothing to generate, no changing costs or production. It just does this thing. Vs. solar, which is beholden to myriad other factors.

I really don't agree with - solar is maintenance free, by design. set it and forget it. And the production is very consistent within seasonal variation. I've talked to people still getting 70% output from their Motorola panels made in the 1970s.

The guy I talked to was great, helped a lot. Estimated payback time with more efficient and reliable (which is to say, more expensive) panels could be about 7 years, which is not bad. And cost would in theory be reduced by 40% or so once you take into account tax rebates and SRECs and whatnot, with a lot of that coming back to you more or less the first year. Though it's still a *considerable* initial cash expenditure. Obviously a lower outright price would be better than a higher price with a promise of refunds, but that's not where we're at.

I think my friend's thing with geothermal is that the energy being generated is constant. It's not linked to sun or shade or snow or cloud cover or whatever, it's just there, year-round. There is no degradation of panels or reduction of panel efficiency, there is no fear of needing (or wanting) to upgrade in the near future, and it covers the biggest drag on a lot of homes, heating and cooling. Of course, it costs a lot more to install! But for example, solar, the Panasonic panels the guy prefers (with iirc solar edge inverter) have a 25 year warranty, which is great ... except who knows how things will look in 25 years, in terms of technology and options and the like. A similar consideration is that when it comes time for a new roof, the panels have to be removed and replaced, too, which could add thousands to the cost. And so on.

There is no degradation of panels or reduction of panel efficiency

this is not a thing that happens, panels have a 25-year output warranty for a reason, and work for even longer as noted above

no fear of needing (or wanting) to upgrade in the near future

also not an issue - don't replace existing panels to upgrade, just add more on a newer inverter.

the biggest drag on a lot of homes, heating and cooling

OK this I agree with.

fwiw my parents have had many painful and expensive difficulties with their geothermal system, they have had no issue with the solar at all.

sure there's an early-adopter price tag still. but as you have seen, the numbers are good in terms of IRR.

My mom has geothermal and loves it, but is not really a candidate for solar.

And panels absolutely do degrade, however slightly. So says the guy I just spoke with and everything I've seen. The cheaper the panel, the quicker (or more) they will start to degrade. The more expensive the panel (like the ones he was pitching), the better they work and the longer they work before any significantly reduced returns (plus better warranties). Granted, around 1% annual decline in productivity is not that big, but that still means 10% after 10 years, and so on, which is not nothing. If we were to, say, want to sell our house in ten years, solar may factor as a selling point, but esp. if we can say it offsets 100% of the house's consumption. It's still good to say 90%, or 85%, but it may not hit that magic psychological number, imo, to get the ideal ROI.

And adding to the system in the future obviously costs money, too. Just things to consider.

it's way less than 1% a year degradation, more like 1/4 of a %

there's a reason they guarantee >80% output for 25 years, 1% a year would be a lot more than that

and yeah you are correct that "100% coverage" is often not a good idea in terms of ROI

Just googling I saw something like an average of .5% annual degradation, and that's linked, like output and efficiency, to quality, which is to say, cost. But yeah, that's a relatively minor concern. Degradation, not cost, that is. A higher priced system here would go for around $22K. A lower cost system would go for around $18k. Both are huge numbers, and if you finance, obviously that number goes up.

fwiw that amount sounds just about right for installed cost on 5-6 KW

I just got his formal pitch, if you're curious, but it includes:

Panel degradation rate: 3% in year 1; 0.26% years 2-25 - 90% efficient @ yr 25

ah that's really interesting! thanks. I did not know that more degradation was assumed in year 1.

After saying my roof isn't great for solar I'm now starting to thing I should jump on this. The Roof is bad because it is flat and mainly taken up by my roof deck, but havingng Saturday up their a lot the shading on the exposed parts isn't actually as bad as I thought and now you can get a 400W standard size panel(SunPower), I could actually get some useful production out of it. There's an outside chance I could squeeze 6 on the eastern end of the roof and 2 on the western end, really its probably 4 and 2 but that could still be 2.4kW. Panels would probably have to be flat rather than on tilt frames or the homeowners association would flip and the shading means I'd have to have micro inverters (Enphase) or optimisers (SolarEdge) to get the best out of a system.

I've had the Enphase option priced out and it comes in at AU$3.74/W which makes me wince, especially as we won't qualify for the current VIC government rebate which would bring that down. I've got a mate going through the same process and his (much bigger) system is quoted out at $1.22/W or AU$1.08/W if he gets the rebate. Thats on a SolarEdge System with optimisers and and Longi 350W Mono PERC panels.

Not that it's really about payback but It would take me about 10 years to breakeven on that

26% solar tax credit extended for 2 years as part of the COVID bill, definitely a good thing

https://www.solarpowerworldonline.com/2020/12/solar-investment-tax-credit-extended-at-26-for-two-additional-years/

even better news

https://pv-magazine-usa.com/2022/07/28/solar-investment-tax-credit-to-be-extended-10-years-at-30/

Dunno if I mentioned it, but we did end up getting solar and have been very happy with it so far.

what inverter type, do you know?

also, Josh, note this key provision:

"The tax credit applies to residential adopters of solar technology. If the bill is passed, the 30% credit will be retroactively applied to anyone who installed their system since the beginning of 2022."

We had it done in 2020, so already got whatever rebates and whatnot we were expecting.

As for inverter type, I believe we have a Solar Edge Single Phase Inverter with HD-Wave.

i just got quoted £9k for installation of 10 panels. that includes batteries & inverter. Looking at my current energy consumption it would supply about the same amount of energy we use (though a bit more in the summer than we need, and a bit less in the winter than we need... grr)

10 x 425w Jinko N-Type All Black Solar Panels
3.7 kWh Fox ESS Inverter
5.8 kWh of Fox ESS Battery Storage.

thinkin about it...

so 4.25 KW, approx $11.5K, just under $3 a watt, that's a solid competitive price imho

especially with batteries

I do have one suggestion, which is to buy 1 or 2 extra panels and keep them around in yr garage or wherever, because five years from now if one breaks you probably won't be able to replace it wil one of similar dimensions. I hear this sad story like every couple of weeks at my job. Panel from 10 years ago hit with golfball or whatever, like yeah the "warranty" is still good but it's a moot point when panel design changes so fast

huh! I never thought of that. thanks for the feeback - it's so hard to know what yardsticks to use with any of this

for sure, ask me anything!

I've wanted to put solar on my property for so long. We had a rep come by some years back and when they showed the proposal, because we have so many trees around the property and the roof angles aren't pointing in the right direction - we were only going to get something like 30% of our usage from it. If we wanted to increase that we'd have to completely reconfigure the placement and it was going to turn into a completely unsightly mess. Have been considering geothermal as an alternative.

Think ours was just under £10k for a similar setup. got it installed when energy prices were mad and looked like we'd make it back in just under 10 years. prices have come down now so it's less of a saving but still good to have and we can add panels if we want.

Here's a question sleeve. i have a sloped roof, with the slopes facing E & W. not ideal but whatever. i also have a kitchen extension with what's essentially a flat roof. panels there COULD face south if we wanted. but the place i got the quote from told me that inverters can only handle two orientations at a time, so if i wanted to do that i'd have to get a second inverter. so i think the options would be

- 5 W panels, 5 E panels
- 5 W panels, 5 S panels (on flat roof)
- 5 W panels, 5 E panels, 5 MORE E panels (on flat roof)

or i get a second inverter to do the 15 panels in three different orientations.. but they told me that would be more expensive than it's worth

forget about the E facing slope and do W and S. or, forget about

whoops - stray editing cruft at the end there

Also... how long does charge actually stay in the batteries? I realise I'm not exactly going to be able to store the extra summer power for the winter, but... overnight? Two weeks? HOW DO IT WORK

haha ok bear with me here

1. don't do three azimuths, stick with south and west as those are typically most effective. especially if you have time-of-use rates that go up in the afternoon. so this is option #2 of yours.

2. the cool thing about lithium batteries is that they can hold charge for months on end with no issue! but the real use of batteries (assuming outages aren't a regular issue) is to use them for "peak shaving", basically you run off the batteries when power is expensive, and run off the grid (filling the batteries back up) when power is cheap.

OK I have a question! The south facing part of our roof is large enough for about nine panels, but the skylights mean that according to the three companies we got quotes from we can't fit any at all. I think if we could get smaller panels we could get some coverage but my vague efforts to find any (or rather companies that would supply and fit them) have proved fruitless. Are smaller panels (not titchy, maybe half size) a thing at all?

yes, smaller panels are out there, but they are not usually UL listed, meaning they can't be used in grid-tied systems. people use them for off-grid. however, Rich Solar does make a newer 250W model that is smaller, and is UL listed:
https://richsolar.com/products/250-watt-solar-panel

but, keep in mind that depending on where you live, the panels may also need to be listed in the CEC database to be part of a grid-tied setup. and although the Rich panels are "UL certified", they are not listed by the CEC: https://www.energy.ca.gov/media/2367

(CEC = California Energy Commission, who publish official estimates of the actual power produced by various panel models, which utilities use in their agreements w/customers)

thanks! I'm in the uk but I'll see if 250w panels are available over here. though given the reduced coverage even those would give us I've gone a bit cooler on the idea. I'm waiting to see if the new government will bring back subsidies.

UL doesn’t matter for UK it’s UKCA (fka CE, that matters)

More is better. I’d go three aspect ratios f you can but you’d want to get a quote on a micro inverter (eg. Enphase) or optimizer system (eg. SolarEdge), you may also be able to find a 3 string inverter. An old colleague went to work for solar edge in the UK and he might be able to scare up the name of a good installer.

Few considerations.

Down here I’d pick east west over throwing in a southern (ok northern down here) aspect but I think the high latitude means you’ll really value the southern aspect in the winter.

Not sure what the UK rules are but oversize the arrays to the inverter, multi aspect means there never all going to be at peak production. 12 panels is 5.1kW of panel capacity so 4.25kW of inverter is fine, could even go a bit lower depending on what they range, but at 8 panels (3.4kW) it’s a 3kW or maybe even a bit less that works for you.

In that latter scenario, depending on home working patterns, you might struggle to get much use out of a battery (although I may be applying Australian logic where AC and poor insulation drive up consumption).

Can you get your interval meter data, and has your installer taken that into consideration before quoting/selling you a battery?

thanks Ed!

The other thing to look at is what an energy retailer will do for you if you sign it up to their product. Octopus and Ovo have been pretty active at this. (I should really go take a look at the octopus product because one of our local retailers has bought a massive chunk of them).

Btw, have you got rid of gas because that might be a better investment than solar?

Btw, have you got rid of gas because that might be a better investment than solar?

I thought one of the main points of going solar was to mitigate carbon-based energy sources? or is it purely economic

It’s both. In a rapidly decarbonising grid like the one in the UK removing the gas connection means you move to much more efficient tech like induction cookers and heatpump hot water and heating so your overall energy demand goes down.

Plus you get rid of gas which suffer from a massive fugitive emissions problem all along the supply chain somewhere between 4 & 10% lost to the atmosphere - methane is 40 more potent as a greenhouse gas than carbon dioxide.

Ideally you’d do both, you’ll get more out of a solar system if everything is electric. however it’s almost always better to lower demand first; whether that’s through highly efficient electric appliances, insulation, shading, painting your house the right colour etc. etc.

I have a gas range (cooker) in my apartment and a couple years ago I finally bought an electric kettle, realizing that I was using gas to boil fucking water

but I'm doing pretty good because probably 2/3 (or more) of my utility bills say "no payment due," meaning that the credits for low-usage outweigh what I am using day to day.. maybe because I'm home in the day working, and leave in the early evening when usage is highest

Ledge, Japan is very good at small, and even shaped, solar panels to maximise roof coverage on small pitched roofs. They are pretty expensive and Japan gave up on exporting solar years ago.

https://jp.sharp/sunvista/feature/blacksolar/images/blacksolar_design.webp

https://jp.sharp/sunvista/feature/blacksolar/images/blacksolar_roofit04.webp

Here’s one that’s been bugging me: is it important to consider the age of the roof? I’ve got asphalt shingles that will probably need to be replaced in five or six years. Once the panels are installed, is it a huge pain to have roof work done afterwards?

Absolutely- you’ll get 20 years plus out of the panels and taking them off and putting them back on costs as much as installing them in the first place. So fix your roof first. You might get a contractor who will put the panels on when they put the new roof on - whilst they have the scaffolding up, but of course it costs a lot to do two major projects at once and the saving will be modest over staging it over a couple of years.

(Also new roof is an opportunity to upgrade your insulation and get it the right colour for your climate)

in the US at least, you can add the cost of reroofing the square footage with solar panels into your total that you get the tax credit on - in other words, whatever % of your roof ends up being covered with solar, you can add that reroofing cost into your grand total that you get the 30% tax credit on

Once you get solar power panels installed, does it work pretty well to charge an electric vehicle off it as well?

I have a relative with an EV who's thinking of getting panels for his home, and our family was thinking of getting this as a Christmas gift if he does.

It works great. However you have to be home when the sun is shining to charge the car.

Depending on how much they drive, if the car is parked up a few days a week when the sun is shining then they’ll be getting their mobility energy from the roof.

For maximum effect you need an EV charger that either integrates with the solar inverter or has the ability to follow the solar output. The solar installer should be able to sort this out.

The wallbox charger definitely does this, as do many others.

Didn't know this:

The smokestacks on the aging Sherco coal power plant tower over gleaming solar panels that stretch across thousands of acres of farmland. The polluting coal plant is on its way out, scheduled for retirement in the next five years. It’s generated billions of dollars’ worth of electricity in its 50-year life, but the most valuable of its parts is the plug — how it connects to the grid that powers our homes. Instead of letting it go to waste as the fossil fuel plant closes, Xcel Energy is going to leave it plugged in to connect the largest solar project in the Upper Midwest, and one of the largest in the entire country, directly to the grid.

Repurposing the so-called interconnection system is short-circuiting what could have been seven years of bureaucracy and red tape to get this electricity distributed to its customers. Experts say this is the secret to solving America’s clean energy dilemma: There is more electricity from clean energy waiting to get connected to the grid than the entire amount of energy currently on the grid. The years-long delays are an existential threat to many projects’ chances of getting built...The US could essentially double the capacity of its electrical grid overnight by plugging renewables projects into old fossil fuel power plants, University of California Berkeley researchers found, whether they be coal, gas or oil. And projects could be plugged into existing plants, not just ones that are retiring.

There is more electricity from clean energy waiting to get connected to the grid than the entire amount of energy currently on the grid.

I don't think people grasp the absolutely insane scale/what this represents. This is all because of Biden (and some serious market forces). When people complain about Dems climate policies it makes my head explode.

Shakey, thinking about doing solar soon as we probably need a new roof next year. Curious if you have any thoughts on best way to do it. Generally I understand my house is a good candidate (large, south facing roof space, no major tree blockage).

the economics of it depend more on where you live and what the utilities' policies/rates are (if you're in California, my advice is don't bother). To be clear though I don't deal with residential systems so it's not really my area.

also in that link they're talking about utility-scale generation, which is completely different than systems that are on residences, commercial properties etc.

Hi, residential expert here. I'd add that if you get a battery, California can still be worth it with peak shaving and other time-of-use tricks.

I think man alive is in NY?

average payback time is just under 8 years in New York fwiw

https://www.energysage.com/local-data/solar/ny/

FWIW we already have a geothermal-based electric heat pump and now an EV too, so there’s added benefit to being able to power that stuff off the solar.

I am in NY. Good companies to use?

ha no idea, look for ones that have good reviews and have been in business for at least 10 years?

also, I suggest buying a few extra panels and storing them in case one gets broken, after a few years they will be obsolete and impossible to replace.

Any long-term concerns about roof damage when getting panels installed, namely leaks? My house has a flat roof, and I live in a foggy area.

for flat roofs, you can get non-penetrating mounts, the only issue there is they use concrete blocks as ballast so weight loads can become an issue. But IronRidge makes flat roof mount solution using ballast for sure. I would not recommend a penetrating mount for a flat roof.

wild stuff

https://www.dw.com/en/how-hackers-capture-your-solar-panels-and-cause-grid-havoc/a-71593448

Interesting. On the wider US grid, solar capacity comes into the resource plan like any other, so if it suddenly drops to zero other fast-to-spin-up resources (wind, smaller hydro here in WA, the battery reserves of plugged in electric vehicles) are brought online to fill the gap. But definitely they should use stronger passwords my god.

yah they use VE.Can for tons of stuff like Victron, tombot hates that shit b/c it is also used in other industries and has zero opsec

and also Jaq it is really interesting how renewable-plus-storage has become the default for peak smoothing, replacing the gas peakers.

Agreed! Now that storage tech has finally gotten in the ballpark for feasibility!

Btw, I'm likely going back part time with [redacted previous employer] in a couple months so I'll be even more hands on with utility stuff again.

oh cool. PS follow commercialsolarguy on bsky, good stuff

id love lots and lots of detailed techy and etc solar discussion even tho there's no prospect of my adding anything to our existing setup due to space constraints

(xp) Done, thx! I like his "cup of coffee and a fruit cup" bet

xp well I still like Enphase and their micro-inverter/battery setup, altho I just had a guy bail on a purchase and return a smaller system b/c it costs too much to configure it for outage backup (where you don't even need a battery, the panels put out power (while the sun is shining) through a special circuit if the grid goes down). but it scales well once you get to 10+ panels. apparently most solar inverter companies are having a hard time right now, not really sure why.

dmac I forget what brand of inverter u have?

it came preinstalled with house im absolutely clueless meself

lol send pics <3