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Solar panels reduced my electric bill in 2022

mattbruenig.com

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Re: Solar panels reduced my electric bill in 2022

#321

Post by baq »

jrochkind1 wrote: post #279
dahfizz wrote: post #273

Earlier quoted context omitted.

> You can still totally offset your own actual consumption at retail rate AFAIK, most home solar is not set up this way. You don't use the energy from your solar panels. The solar panels feed directly into the grid, and your usage comes directly out of the grid. So if you use 100kwh, and generate 100kwh, then you will pay 100kwh at retail rate, and receive 100kwh at wholesale rate.

Hm, while I understand what you mean about where the actual energy goes, my understanding of how the costs are accounted are that there isn't any separate metering for "electricity out" vs "electricity in". The Solar out actually runs your meter backwards, so does actually reduce the amount the meter shows you owing to charge you at the retail rate. There is no metering present to make it possible to charge you for t…

My 3.5kWp PV installation is hooked up to one phase in the house and that power is definitely being used without being counted by the (2-way) meter.

Re: Solar panels reduced my electric bill in 2022

#322

Post by baq »

jackmott42 wrote: post #194
praxulus wrote: post #144

Earlier quoted context omitted.

Net metering just doesn't make sense though. Everyone who wants to rely on the grid for power availability ought to pay for grid upkeep costs. Net metering would make sense if it came on top of a baseline "connectivity fee" that covered grid maintenance, but that's not the current policy, would likely be politically infeasible, and would hurt rooftop solar customers financially anyway. Subsidizing solar is a perfectl…

Agreed, at some point the grid will need to spend on storage to enable more solar users. So either you need to have a fee to pay for that, or push the storage burden onto the end users. Make that cost apparent and force people to deal with it and we will find creative ways to do so (like more EV vehicles that can act as storage, as the Ford Lightning can)

More likely at some point it will be uneconomical to run PV without attached storage. As an added bonus you’ll be able to pull cheap power on the winter from the grid overnight if you have that kind of tariff available.

Re: Solar panels reduced my electric bill in 2022

#323

Post by Ekaros »

chongli wrote: post #98
swagasaurus-rex wrote: post #3

> The unsubsidized all-in price for buying and installing the panels was $25,525.43... after counting this $6,636.61 tax credit, the subsidized price was $18,888.82 Looks like a 7 year return on investment after subsidies, 10 years without.

7-10 years to break even. If the panels last 15 years you'll see a net return of $21,416 on investment of $18,888. If they last 25 years, that net return grows to $48,186. In either case it works out to an annual rate of return of 5%, assuming electricity prices stay the same (BIG ASSUMPTION) and also assuming the weather doesn't change to get cloudier or more violent (also a big assumption).

Also there is a question if electricity produced by panels will match the peak demand or in general is utilized. Scenario where solar is overbuild and thus power generated by it has near zero price for large part of the day might happen.

Re: Solar panels reduced my electric bill in 2022

#324

Post by KaiserPro »

In the UK, I've had a battery plus solar for just over a year.

its a 5kwp set of panels and a 13kwhr battery. From mid march to late November, we only drew from the grid once (that was because we had a portable hottub setup, which took ~28kwhr to heat up.)

Its raining and january and december are shit months for solar, well mostly because of the short days. December we were 45% independent from the grid.

Currently we do not have heating or cooling from electricity. If that were the case we'd need 10kwp plus more storage.

Re: Solar panels reduced my electric bill in 2022

#325

Post by marvin »

maerF0x0 wrote: post #151
throwaquestion5 wrote: post #135

Earlier quoted context omitted.

They took 7 months to install the panels. I'm sure times during all that the OP thought if they forgot about him, called them to ask for a installation date, etc. As a way to curb any thought about undue wait time, the company made a contract guaranteeing installation between 6 month after signing. They didn't comply and the loan lapsed. Now the company needed to negotiate a new contract with OP or go for the legal r…

> There is nothing unethical about this. I dont consider strong arming someone due to your now advantageous position against something you previously agreed upon and reasonably similarly delivered (7 months instead of 6, we're not talking about multiple years later here). A similar ethical framework would allow someone in marriage say "I quit my job, can get alimony from you, better do as I say or I'm filing for divo…

Expand the argument to the economy as a whole, and it's just the Prisoner's Dilemma. You'll get screwed by someone else someday, the solar company will screw someone other than you etc. I'll certainly agree it would be better if everyone cooperated. Whether it's unethical depends on your ethical framework.

Re: Solar panels reduced my electric bill in 2022

#326

Post by TMWNN »

RC_ITR wrote: post #116
frankfrankfrank wrote: post #27

Earlier quoted context omitted.

That is technically true, but why is no one asking how and why his electricity bill is $223 at minimum, plied higher since the bill was only reduced by that amount. Also, “subsidies” are really just a quaint term for “made the working and lower middle class that can’t pay for such exorbitant luxuries pay for it through taxes and inflation”. I’m always a bit confused if seemingly otherwise smart people simply don’t un…

>Would anyone like to subsidize my next restaurant visit by paying for my entree? No? But making someone unknown working class person pay for my $25,000 solar install through inflation is ok? It's amazing how ignorant people can be to the world around them. Let's assume you live in the US, since the article is dealing with those subsidies. The food you're eating - c. 20% of US farm income is subsidies [0] The employe…

>The car you drove to the restaurant in - the US Federal government subsidized your gas (ever wonder why US gas is cheaper than Canada/EU?)

US gas is cheaper than elsewhere in the developed world because a) the US is self-sufficient in terms of supply and, more importantly, b) US fuel taxes are less.

If you actually read the EESI paper you cited, you see that the "subsidies", whether direct or indirect, are actually varying accounting treatments; basically, the same amount of taxes are collected but over a longer period of time. In any case, even if you were to remove all the direct "subsidies", the paper does not claim that tax revenue would rise more than about $40 billion over about a decade. $4 billion a year is a pittance for a federal government that collected $4.9 trillion in 2022.

Re: Solar panels reduced my electric bill in 2022

#327

Post by axus »

secabeen wrote: post #155
eppp wrote: post #128

Earlier quoted context omitted.

Because net metering is forcing the utility to purchase power at the retail rate. It doesn't make any sense. It isn't a profit margin issue. There is a massive infrastructure and expense to deliver wholesale power to an individual customer and it has to be recouped. Either you sell back your power at some percent of wholesale or solar installs need to get a corresponding increased delivery fee.

What we need is a fundamental change in electricity billing. The value in a grid connection is in its reliability, availability and demand response (you can demand anything from 1 Amp to 200 Amps at any time, with no notice). The current usage-only billing model is broken. What we should do is pay a large flat monthly fee for the grid connection, then a lower rate for generation/usage, rather than bundling the delive…

Why do power companies even buy back solar power in the first place? It seems like it's not in their interest to help their customers compete with them.

I do agree there should be a connection fee, like an Internet connection, that covers fixed costs. Watts cost more than bytes, so a usage fee makes sense too.

Re: Solar panels reduced my electric bill in 2022

#328

Post by baq »

manimino wrote: post #298
AndrewGaspar wrote: post #168

Can somebody explain where the return on investment comes from in residential solar? It just strikes me that if there was easy money to be had on solar installations, we'd just get tons of utility scale solar installs (which would likely by more capital efficient) and my utility bill would over time converge on the expected total utility bill for a home with residential solar. Is it just because we're in that transit…

Utility-scale solar is far more efficient than rooftop solar. With rooftop, the panels face whatever direction the roof does. But utility solar fields have panels that rotate to face the sun. Considering that power generation depends on the cosine of the angle between the sun and the panel - angle matters a LOT. Efficiency falls off fast if your angle is bad.

This should be at least somewhat offset by the fact that you generate power approximately where it is consumed, so the grid doesn’t have to grow as much. Turns out it isn’t so simple due to peak demand vs peak production etc but still. I wouldn’t have a problem with plastering PV on half of Nevada.

Re: Solar panels reduced my electric bill in 2022

#329

Post by cogman10 »

treis wrote: post #292
cogman10 wrote: post #197

Earlier quoted context omitted.

That's absolutely how snow on top of the roof works. Most building codes in snow heavy areas have pitch requirements. https://www.atozroofingdenver.com/how-does-roof-pitch-affect...

>That's absolutely how snow on top of the roof works. How do you explain that picture with ~1 foot of snow on the roof's peak?

It's a low pitch roof which allows for a lot more buildup.

Also, if you read the article I linked, you'll know that pitch isn't perfect (pun intended), but it does go a long way in preventing snow buildup. A major snow storm with wind blowing snow in the right direction can twart a high pitched roof. But that sort of condition is a lot more rare.

Re: Solar panels reduced my electric bill in 2022

#330

Post by jefftk »

NotYourLawyer wrote: post #251
acomjean wrote: post #132

Earlier quoted context omitted.

I know someone who did 5000W system for around 15,000 in 2018. Battert/Powerwalls let the solar work when the power goes out. (the dc to ac converters use the 60hz out of the grid to sync. There is no shutoff to the grid so for safety reasons her system shuts down when the power is out).

Oh sure, and I wanted a battery of some kind to keep things running in an outage. I just mean I don’t know why they bid a Powerwall specifically instead of some other battery system.

Any sort of battery system that lets you keep running in an outage is going to be pretty expensive, unfortunately.

But at that point your question isn't "what would be the payback period if I got solar" but "how much is it worth to me to have power when the grid is down". And so not surprisingly many people get solar but don't install a battery.

(Systems that provide a small amount of best-effort when-the-sun-is-shining emergency power when the grid is down seem like they should be a sweet spot here, because they can be implemented very efficiently. Unfortunately a combination of consumers not wanting it, the NEC not prioritizing it, and the shift to microinverters means that instead of adding ~$200 like it did when I got solar several years ago it's now more like $7k)

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