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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

#341

Post by jacquesm »

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…

But you do pay for 'grid upkeep costs', the grid availability is a part of that connection fee, otherwise what would you connect to if not to the grid. Even if you consume zero KWh in a month you will still pay.

Re: Solar panels reduced my electric bill in 2022

#342

Post by jacquesm »

monkeydust wrote: post #267
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…

Just be glad your not in the UK. I pay 35p / kWh down and get only 5p / kWh for excess I sell to grid through Smart Export Guarantee. Price down has doubled in two years and way up has hardly moved. I joked with my neighbour that we should wire up our homes and sell my excess to him at mid point and we would both be better off.

> I joked with my neighbour that we should wire up our homes and sell my excess to him at mid point and we would both be better off.

I've been looking at this but not as a joke and you run into some fairly interesting problems when you start paralleling after the meter. Long story short: don't do this unless you have a lot of electrical engineering chops or you might end up create a liability in case of a leak to ground or an overcurrent situation. This needs some special handling. The best way would be to just create an extra circuit and use a waterproof extension cord to power it, that way all GFPs see their real current and not a fraction of it and you can't accidentally feed into a distribution panel at more current than the breakers see, which is an excellent way to start a fire.

Re: Solar panels reduced my electric bill in 2022

#343

Post by reacharavindh »

monkeydust wrote: post #314
gnicholas wrote: post #296

Earlier quoted context omitted.

Low-effort version, if he has an EV: get a long charging cable and charge him up when you're generating excess.

He doesn't but few on the street do. Could hack something over the summer that provides some charge on my driveway when I am net producing. Not sure if any legal/tax issues with the setup though. An interesting community project.

It might even be a greater option to have a community battery booth(a bank of LFP or the upcoming Sodium ion batteries). Everyone throws their excess energy into it, and it can be a charging station for e-bikes, EVs etc.

Absolutely no clue about legal issues though.

Re: Solar panels reduced my electric bill in 2022

#344

Post by jacquesm »

if you don't have net metering you should consume as much as you can yourself, cook when the sun is out, run your washer / dryer / vacuum / dishwasher and whatever else you have when you have excess power and minimize during the times the sun is below the horizon. 60% self consumption is doable without too much effort, 70 is work and if you get to 80%+ please let me know how you are doing that.

Also: the big trick to running of renewables is conservation comes first, solar second and finally the grid as a fallback for the remainder.

Re: Solar panels reduced my electric bill in 2022

#345

Post by jksmith »

The conversation here seems a bit binary. Maybe I missed a few posts. The whole solar thing is not realized until cooperatives de-grid in favor of their own local grids, along with an arbitrage sharing model. That has the potential to to manage all power needs (including electrical cars). It's a scaling issue sort of in between entirely centralized and rugged individualism.

Of course the tech for this is a real threat for utilities, so it wouldn't surprise me if they would go to any length to stop such and effort. Same could be said for any deflationary tech like micro reactors.

Re: Solar panels reduced my electric bill in 2022

#346

Post by danans »

notJim wrote: post #281
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…

This incentivizes storage and time-shifting usage to solar peak times, which seem to be needed in California. Does anyone know if there are pricing signals to help with that? For example, if I (as a power-plant operator or whatever) found a way to sell electricity right as the sun is going down, am I rewarded for that? As an individual with a solar install, I think this also encourages people to use the energy they p…

> This incentivizes storage and time-shifting usage to solar peak times, which seem to be needed in California. Does anyone know if there are pricing signals to help with that? For example, if I (as a power-plant operator or whatever) found a way to sell electricity right as the sun is going down, am I rewarded for that?

NEM3.0 incentivizes exactly that. It prices exported electricity at the avoided cost rate. During the late summer and early fall, between 7-9PM that can be more than $1/kWh, or 3x the average NEM2.0 rate [1]. Of course to maximize that rate you need to store energy and sell it back at the optimal time.

The average rate with NEM3.0, however, is much lower.

1. https://www.cpuc.ca.gov/-/media/cpuc-website/divisions/energ...

Re: Solar panels reduced my electric bill in 2022

#347

Post by carschno »

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.

This is effectively similar to the "energy price ceiling" that the Netherlands have introduced for this year: https://www.government.nl/topics/energy-crisis/cabinet-plans...

Note: the most recent English document still describes this as "planned", but it has been approved and has gone into effect with the start of 2023.

The difference is though that the state subsidies the "cheaper" rate. When a customer has consumed the subsidized amount of electricity or gas, they pay the full market price.

Re: Solar panels reduced my electric bill in 2022

#348

Post by saltcured »

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…

With PG&E, we have networked meters that report fine-grained usage in order to support the newly standard time-of-use rate plan. It is not an average over a metering period like a month but able to resolve usage at different hours of the day. Even my bill shows peak and off-peak usage as daily bar graphs, and I think I can login to see more fine-grained data at the power company website if I wanted to.

But I agree with the message several posts up. The old net metering was a subsidy and I understand it going away. It makes sense to me at a technical level that you would be billed your fine-grained net usage, so if your solar supports your daytime load then you didn't consume power, but you can't expect daytime excess to 1:1 cancel your nightime grid load, unless you install local batteries to time-shift your own power.

The old net metering did that. People generate excess during the day and consume power at night from the grid and expect it to all cancel out.

Re: Solar panels reduced my electric bill in 2022

#349

Post by koyote »

CorrectHorseBat wrote: post #14

I'm always surprised about the price of solar panels in the US, I think we paid about €1.2/W. It's not like labor is cheap in Belgium.

Australia is even cheaper, I paid around USD 0.6/W for my system (including subsidies, it's closer to USD 1.0/W excluding subsidies). Break-even will be in around 3-4 years.

I noticed (by following the solar sub-reddit) that almost every single US install has either Enphase or Solaredge inverters (which happen to be on the pricier side). I am not sure if that's an indication for the lack of competition but surely this seems like an industry where disruption is possible?

Re: Solar panels reduced my electric bill in 2022

#350

Post by dpierce9 »

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…

Net metering means utilities sell the power your system produces at full price to your neighbor. They pocket the avoided cost of producing and delivering that power (and during price spikes the cost of fuel can be higher than the value of producing power).

Net metering does create stranded assets if everyone does it. But not everyone does. Further, the idea that the utility gains NO benefit from net metering is wrong.

The corresponding view that rate payers are subsidizing solar by paying additional grid costs is wrong. Solar reduces grid demand. This reduces required generation capacity. Capacity is very expensive.

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