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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

#351

Post by pydry »

praxulus wrote: post #144
hbarka wrote: post #109

Assuming you are grid-tied, the reduction of electric bills is predicated on net metering, where the utility company gives you (ideally) 1-for-1 credit for the electricity you produce. In California, this was called NEM 1.0 and NEM 2.0. Every few years the California utilities lobby the Public Utilities Commission (PUC) to chip away at the NEM program. This year the PUC voted unanimously to cut net energy metering an…

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…

This kind of attitude only really make senses if there is a carbon tax.

Net metering is as good a subsidy for green energy which we DIRELY need as any.

Making perfect the enemy of the good is bad enough as a general principle but is 100x worse when the future of the planet is at stake.

Re: Solar panels reduced my electric bill in 2022

#352

Post by danans »

KerrAvon wrote: post #139
hbarka wrote: post #109

Assuming you are grid-tied, the reduction of electric bills is predicated on net metering, where the utility company gives you (ideally) 1-for-1 credit for the electricity you produce. In California, this was called NEM 1.0 and NEM 2.0. Every few years the California utilities lobby the Public Utilities Commission (PUC) to chip away at the NEM program. This year the PUC voted unanimously to cut net energy metering an…

If there’s no net-zero metering, aren’t they incentivizing people to be completely disconnected from the grid, or at least not incentivizing them to be connected? (Which is bad for the grid.) Why would I fuck around with the utility at all if I’m installing enough solar/battery to power my needs?

> Why would I fuck around with the utility at all if I’m installing enough solar/battery to power my needs?

What will you do when it has been raining/cloudy for weeks straight like it has recently in California? For this period, wind has dramatically outproduced solar [1]. Even in the summer/fall, when there was severe wildfire smoke in the area, my solar+battery barely produced anything.

Sure, you can set up a propane generator (very expensive at the size needed for a full house backup), but then you are dependent on the propane-distribution grid. The dirty secret of "no-sacrifice off-grid" lifestyles is how much they are dependent on propane for heating and electricity.

Also, the grid's up-time is going to be better than your home battery setup up-time both because it is constantly maintained and it has access to a greater diversity of energy sources (wind, nuclear, fossil, large-scale storage) that are firmer than anything you can attach to your house.

The fact is that modern living standards (cars, TVs, comfortable temperatures) require a much larger amount of energy and energy-availability than most people can produce on their properties with solar. The additional energy has to be imported somehow, either from the electric grid or as liquid or gaseous fuels.

1. See Renewables Trend at http://www.caiso.com/TodaysOutlook/Pages/supply.html

Re: Solar panels reduced my electric bill in 2022

#354

Post by NotYourLawyer »

jefftk wrote: post #330
NotYourLawyer wrote: post #251

Earlier quoted context omitted.

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-shin…

I get that it’s not gonna pay for itself any time soon, and I’m on board with paying for the privilege of keeping things running when the grid is down. But 50 grand? Come on.

Re: Solar panels reduced my electric bill in 2022

#355

Post by nicoburns »

secabeen wrote: post #276
birken wrote: post #219

Earlier quoted context omitted.

Additionally, the worst strains on the grid are really measured by the peak loads, so if you change billing a way that makes the peak energy less expensive, and therefore disincentivize people to (a) reduce usage at peak times or (b) install solar panels/batteries to mitigate their peak usage, then it actually might make the grid more unreliable. Water is different in that we really only have usage concerns about wat…

Yes, that's what you see in the commercial side, where demand charges based on your highest peak usage in a month are common. However, they are un-intuitive and easy to generate big bills for small amounts of power used, so I agree with the general idea that they're not a good idea for residential users.

You could institute something like time-of-day-based fees based on average demand for residential users without having the large unexpected bill problem.

Re: Solar panels reduced my electric bill in 2022

#356

Post by Kirby64 »

akira2501 wrote: post #241
prettychill wrote: post #5

I am surprised at these power bills, at least in my area the implied "savings" are 2-3 times what my bill is on any given month. Huge house maybe?

I don't find his methods particularly rigorous. He's just taking total generated kWh and multiplying it by current utility rates and then saying this represents savings. Does it, though? We don't know how much of the generated power was actually used instead of sold back into the grid, or if this is even a grid tied installation, and what the return sales rate would be. The only way to actually compare this is to loo…

If you live in a place that does net metering, it truly just is as simple as generated kWh * utility rate. That's what net metering means. Each kWh you provide via solar offsets the cost of a kWh from the grid.

Additionally, if you live in a place where power is $0.20-$0.30/kWh, then $233/mo is not a particularly large amount of electricity, especially for a single-family house. At $0.30/kWh, that's only ~775kWh of electricity.

Re: Solar panels reduced my electric bill in 2022

#357

Post by NotYourLawyer »

JanisErdmanis wrote: post #315
NotYourLawyer wrote: post #42

I looked into solar in 2022. The bid I got for a 9.5 kW system and one Tesla Powerwall ended up being right around $50,000. No thanks.

That's an insane number. 25 solar panels + 9 kW inverter + bindings and wires would result in around 8000$.

Seemed crazy to me too. If it had been $8k plus battery costs I would have done it.

Re: Solar panels reduced my electric bill in 2022

#358

Post by secabeen »

ok_dad wrote: post #335
axus wrote: post #327

Earlier quoted context omitted.

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.

> 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. Good question! The more power you generate locally, the less you need to transmit along expensive infrastructure, so it is actually in the interest of utilities to utilize and pay for all of the generation capacity they can as close to the consumer as possible. You…

> The more power you generate locally, the less you need to transmit along expensive infrastructure,

This is true, but I don't think the savings on infrastructure scales linearly with the distributed power generated. For example, if you generate 1 MW of distributed power, that reduces the load on wires, transformers and towers across the grid, and may even mean you can eventually use cheaper gear at your next replacement, but it's not going to eliminate the baseline costs (towers, wires, transformer sites, etc.) of serving any particular customer or region.

Re: Solar panels reduced my electric bill in 2022

#359

Post by forbiddenlake »

killjoywashere wrote: post #275
moffkalast wrote: post #253

Earlier quoted context omitted.

Why are the leases so problematic? If you don't have the funds nor credit score to finance it, why not just rent out the roof space so to speak? Any return you get from it is better than nothing.

We got a house in San Diego near the bottom of the last market (2012) and I was a medical resident at the time with two school age children. The previous owner had installed electric everything (even had to get a larger trunk line run and breaker panel). So our electric bill was a little nuts, randomly hitting tier 3 pricing and landing $350+ electric bills. For a household with negligible marginal income, that was u…

So why wouldn't you get a lease now?

Re: Solar panels reduced my electric bill in 2022

#360

Post by Nathanael_M »

jeffbee wrote: post #86
Nathanael_M wrote: post #43

Earlier quoted context omitted.

Sorry, life after 25 years? That's WAY higher than I thought. That's incredible.

The idea that PV panels become trash in a decade is a lie promulgated by oil companies. According to NREL, reputable panels degrade as little as 0.1% per year, which means they will still be above 90% of rated output after 100 years. The trashiest panels NREL has tested degrade at 1.1% per year which would put them at 75% rated capacity in 25 years. https://www.nrel.gov/pv/lifetime.html

This is very exciting. Does this mean the biggest continuing expense would be batteries if you wanted to self-sustain with solar?
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