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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

#271

Post by secabeen »

aidenn0 wrote: post #258
prettychill wrote: post #123

Earlier quoted context omitted.

Hottest month for me was aug, I paid around 161 ~$135 1190kWh (charged at ~$0.114 / kWh) ~$10.50 tax ~15.50 other fees/riders which can not be recouped with panels OP is somehow paying ~25c/kWh, though I have to believe they are counting the connections fees etc in their estimate, based on natl averages they would be an outlier for most states. https://www.eia.gov/electricity/state/

Yes, that price is insane! I don't have A/C, do have net metering and do have solar panels, so I intentionally picked the plan with the highest costs during the day in the summers and I pay 24c/kWh only in peak hours during the summer. Author may be a high energy user and on a tiered monthly-usage plan rather than a TOU plan; if that is the case than the solar panels may be saving energy billed at the highest margina…

California rates (not sure the OP is in California, but still) are just high. Lowest Off-Peak rate is $0.22/kWh in my area, and On-Peak (4-9pm) can be as high as $0.62/kWh.

Re: Solar panels reduced my electric bill in 2022

#272

Post by zombielinux »

CTmystery wrote: post #199
cheald wrote: post #126

Earlier quoted context omitted.

Solar won't keep you online through a power outage. The inverter is required by law to cut power from solar panels when there is not power from the grid, so as to avoid feeding electricity back into the grid lines (which technicians may be working on!) - this is known as anti-islanding protection. If you want to be online through a grid outage you need a battery array.

From a circuit perspective, it seems trivial to open a switch back to the grid to prevent grid-feed, while still feeding the internal circuit that is the house. Can you help me understand why this is hard?

The problem is that its not a DC connection to the grid.

Not only do you have to match voltage on re-connection, but you have to match frequency AND phase.

Its "doable" but to do so reliably without a stable reference can be challenging. That's why the DC requirement is there. They want some form of reliable power to well tested electronics to match phase and frequency when the grid comes back up.

A heavily loaded AC line will drift in voltage and frequency stability (say when your AC kicks on and browns out your solar panels).

Re: Solar panels reduced my electric bill in 2022

#273

Post by dahfizz »

jrochkind1 wrote: post #247
ihaveajob wrote: post #217

Earlier quoted context omitted.

Yes it is, there's a connection fee of approximately $10/month for that same reason. Net metering is a totally unrelated topic. What's being argued about is the rate. Until now, rooftop solar customers get a retail-level payback for excess production sent to the grid. Under the proposal, this payback would be at the wholesale price, which is significantly lower.

You can still totally offset your own actual consumption at retail rate, but any negative over your actual consumption for the month, you only get paid cash at wholesale rate? Without knowing anything about this or any context... that does not seem unreasonable to me. Note that OP didn't even require net negative at all to have it still totally be a great investment. He only offest a portion of his actual usage. So n…

> 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.

Re: Solar panels reduced my electric bill in 2022

#274

Post by _whiteCaps_ »

VintageLight wrote: post #120
jefftk wrote: post #35

Earlier quoted context omitted.

Having 21 panels requires a rectangle 17ft by 24ft (each panel is 5.4ft by 3.25ft). That's far from an estate: if it's a two story home with a flat roof you're talking 816sqft compared to a US median of 2,300sqft.

1. Most roofs aren't flat. 2. For pitched roofs, you're only going to want to install on the south or west facing sides. So only some percentage of your roof area is ideal.

Wouldn't the panels be the same pitch as the roof, so you'd reduce the footprint there as well?

Re: Solar panels reduced my electric bill in 2022

#275

Post by killjoywashere »

moffkalast wrote: post #253
isanengineer wrote: post #77

I worked in the solar industry for years and this is a very good summary of the residential install process from the customer side. I’ll also second one of the main points of the author: do NOT get a solar lease. Either finance it through a solar loan or pay cash. A good solar company will not push you into a lease. If they try, talk to someone else.

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 unpleasant. We had 0 capital to play with but switching to solar was a no brainer. Even the lease is cheaper than paying PG&E.

Would I do it that way again? Probably not. But I have more wiggle room now.

Re: Solar panels reduced my electric bill in 2022

#276

Post by secabeen »

birken wrote: post #219
hinkley wrote: post #184

Earlier quoted context omitted.

I think you’re missing a different piece of the puzzle here which is that if I pay $10 for the first gallon of water and next to nothing for the next 500, I have an incentive to use more water and not less. I’ve paid for it anyway. When you’re trying to solve public policy problems especially where conservation is concerned the notion of math gets complicated very quickly.

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.

Re: Solar panels reduced my electric bill in 2022

#277

Post by hinkley »

birken wrote: post #219
hinkley wrote: post #184

Earlier quoted context omitted.

I think you’re missing a different piece of the puzzle here which is that if I pay $10 for the first gallon of water and next to nothing for the next 500, I have an incentive to use more water and not less. I’ve paid for it anyway. When you’re trying to solve public policy problems especially where conservation is concerned the notion of math gets complicated very quickly.

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…

I’m told that Industry gets charged not by how much current they draw but by how much it distorts the grid power waveforms. In fact there are experimental designs out there for power correction facilities that delay the waveforms by for instance 90% of a wavelength (so everything lines up again) and convert the delta to DC to store in batteries. The battery power can be used for their own purposes or to reinject in low voltage situations.

Re: Solar panels reduced my electric bill in 2022

#278

Post by [deleted] »

CTmystery wrote: post #199
cheald wrote: post #126

Earlier quoted context omitted.

Solar won't keep you online through a power outage. The inverter is required by law to cut power from solar panels when there is not power from the grid, so as to avoid feeding electricity back into the grid lines (which technicians may be working on!) - this is known as anti-islanding protection. If you want to be online through a grid outage you need a battery array.

From a circuit perspective, it seems trivial to open a switch back to the grid to prevent grid-feed, while still feeding the internal circuit that is the house. Can you help me understand why this is hard?

[deleted]

Re: Solar panels reduced my electric bill in 2022

#279

Post by jrochkind1 »

dahfizz wrote: post #273
jrochkind1 wrote: post #247

Earlier quoted context omitted.

You can still totally offset your own actual consumption at retail rate, but any negative over your actual consumption for the month, you only get paid cash at wholesale rate? Without knowing anything about this or any context... that does not seem unreasonable to me. Note that OP didn't even require net negative at all to have it still totally be a great investment. He only offest a portion of his actual usage. So n…

> 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 the 100kwh you used at one rate, but then you pay you for the 100kwh you generated at a different rate. The electricity you generate runs the meter backwards, and reduces what you are charged for consumption -- which monetarily means you are "being paid" for it at the retail rate.

But if your meter goes negative in a given time period, they can tell at the meter you actually generated more than consumed, and could pay you out a different rate for that. (Or as OP notices, in some places, they allow you offset your use, but don't actually pay out for net negative at all. )

This is why the metering is called "net", it's your "net" use, consumption minus generation. I believe that's how it works for my friends here in Baltimore who have solar panels.

Are there other places in the USA where they install more sophisticated metering capable of separately metering out and in, and charge different rates for it?

Or, anyway, since we're talking about California, if anyone wants to clarify how it actually is going to work in CA, rather than speaking in hypotheticals based on our theoretical understanding of how things work, that would be even better!

Re: Solar panels reduced my electric bill in 2022

#280

Post by hinkley »

notJim wrote: post #225
hinkley wrote: post #184

Earlier quoted context omitted.

I think you’re missing a different piece of the puzzle here which is that if I pay $10 for the first gallon of water and next to nothing for the next 500, I have an incentive to use more water and not less. I’ve paid for it anyway. When you’re trying to solve public policy problems especially where conservation is concerned the notion of math gets complicated very quickly.

Theoretically, you could add a third type of charge related to the externalities associated with your consumption. I'm not sure exactly how the accounting would work, but maybe an escalating fee based on the amount you consume. My utility actually does this with electricity, where the rate goes up after your first 1000 kWh. Obviously this could get more elaborate.

That’s a fancy way to say carbon tax, which I agree with but also recognize has been turned into a political landmine.

Also I thought PG&E still had the reverse situation, of people voluntarily paying more for green power.

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