Solar panels reduced my electric bill in 2022 • Hacker News Board

Re: Solar panels reduced my electric bill in 2022

#221

Post by kibwen » Tue, Jan 03, 2023, 7:05 PM UTC

shostack wrote: post #137

chongli wrote: post #98

Earlier quoted context omitted.

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).

Is net return all that matters? Seems like with increasing heat waves, power outages etc, being able to generate and store your own electricity has value from a resiliency standpoint.

Note that merely having solar panels on your house doesn't automatically let you run your house off of the panels in the event that the grid goes down. Firstly, if you're connected to the grid, then a single house trying to push power into a downed grid would be like trying to refill the ocean with a super soaker. Even with lots of houses doing it, the frequency would be wildly unstable at best and cause damage to equipment. Secondly, it poses dangers for lineworkers who are probably trying to resolve the outage, by putting surprise voltage into wires.

It's certainly possible to have a solar installation that does let you disconnect from the grid, but it requires extra hardware (including a battery backup).

Re: Solar panels reduced my electric bill in 2022

#222

Post by spockz » Tue, Jan 03, 2023, 7:06 PM UTC

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…

In the Netherlands you a fixed price for being connected. The amount varies on the size of the connection. Usually 1 phase 40A is as expensive as 3 phase 25A. Anything above that easily triples in price. Aside from this you have net metering still and you pay for what you consume. No “usage bundle” is included in the connection fee.

Also, the companies for infrastructure and that provide the actual energy are separate but the energy supplier charges for the infrastructure provider. The infrastructure provider is semi privatised while the energy supplier is fully privatised.

It kind of works, except that we need like everyone else, to upgrade the power grids to deal with increased consumption and we haven’t invested in that.

Re: Solar panels reduced my electric bill in 2022

#223

Post by swayvil » Tue, Jan 03, 2023, 7:06 PM UTC

mdorazio wrote: post #145

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…

Over the last 8 quarters their average profit margin is a whopping 3.25%. If you think that’s just too high I’m not sure what to tell you. An alternate way to look at the CA rule change is that CA needs more installed storage to shore up the shitty grid, and incentivizing people to install solar alone via net metering isn’t a great idea anymore. Remember that peak power demand is right around and just after sunset.

3.25% of fifty bazillion ain't so bad.

Re: Solar panels reduced my electric bill in 2022

#224

Post by Someone1234 » Tue, Jan 03, 2023, 7:06 PM UTC

foobarian wrote: post #170

I have a pretty ideally angled roof near Boston and was considering a solar setup. However as far as I can tell we won't get paid for excess generation in any given month, so since we don't really use much electricity it seems this is not a good investment. Are there any common updates possible to take advantage of the excess power? Before ETH switched to POS I thought about mining crypto... otherwise we could switch…

> otherwise we could switch to electric heat but that is a huge outlay.

You can walk into any major retailer, buy a space heater, and plug it into any outlet in your home. Keep in mind that your gas furnace is turned on/off using a thermostat and temperature setting, so if you reduce the set-point e.g. 1 degree, and then either locate the coldest parts of your home or areas you want to prioritize (e.g. livingrooms/bedrooms), you can then target space heaters into that location to offset the savings from gas.

In terms of deployment heating or cooling, electric heat is the cheapest and easiest. You're just thinking that it must be whole-home or nothing, which isn't the case, you can reduce your whole-home and spot-heat as needed.

Re: Solar panels reduced my electric bill in 2022

#225

Post by notJim » Tue, Jan 03, 2023, 7:07 PM UTC

hinkley wrote: post #184

secabeen wrote: post #155

Earlier quoted context omitted.

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…

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.

Re: Solar panels reduced my electric bill in 2022

#226

Post by BrentOzar » Tue, Jan 03, 2023, 7:07 PM UTC

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…

> Can somebody explain where the return on investment comes from in residential solar?

During the run-up on housing prices over the last couple of years, there was a belief that an owned solar system would raise your house's sale price in much the same way that a kitchen or bathroom renovation would.

Couple that with the supply and labor constraints, which made it hard to get the panels, battery, and installers you wanted in a timely basis - that raised the perceived home value yet again, because if you wanted to add your own solar later, it wasn't seen as easily doable.

I don't know that the ROI was ever great, but with both of those factors gone today, it's worse than it ever was. (Source: shopped for homes in 2020-2021, bought in 2022, tried to get solar installed, ROI made no sense.)

Re: Solar panels reduced my electric bill in 2022

#227

Post by gnicholas » Tue, Jan 03, 2023, 7:07 PM UTC

> if you use a 5 percent discount rate, 20 years of $2,677 of annual electricity bill savings yields a net present value of $33,361.

Yes, but with an 8% discount rate, the PV is $26,283. It's true that the cost of electricity will probably rise over time, as he notes. But current interest rates make this a much less attractive proposition from a financial perspective (that is, assuming you don't care about solar generation for environmental reasons). The homeowner takes on significant risk, and the gain is not all that great. Your panels can be destroyed by hurricane, earthquake, or falling trees, rendering them worthless, for example.

I'm not saying this isn't worth doing, just that the financial calculations seem a bit flawed in today's economic environment.

Re: Solar panels reduced my electric bill in 2022

#228

Post by foobiekr » Tue, Jan 03, 2023, 7:08 PM UTC

heythere22 wrote: post #133

ck2 wrote: post #64

Weird question and probably rare but what happens if solar array is hit by lighting? Are they insured? Do they get damaged? Does the inverter/batteries get damaged or is there likely a circuit breaker?

> Are they insured? You are better off if you add them to your already existing coverage for your roof. So probably yes. > Do they get damaged? You typically don't expect trees to fall onto your solar panels. So where should any damage come from?

Hail.

Re: Solar panels reduced my electric bill in 2022

#229

Post by ceejayoz » Tue, Jan 03, 2023, 7:09 PM UTC

gnicholas wrote: post #227

> if you use a 5 percent discount rate, 20 years of $2,677 of annual electricity bill savings yields a net present value of $33,361. Yes, but with an 8% discount rate, the PV is $26,283. It's true that the cost of electricity will probably rise over time, as he notes. But current interest rates make this a much less attractive proposition from a financial perspective (that is, assuming you don't care about solar gene…

> Your panels can be destroyed by hurricane, earthquake, or falling trees, rendering them worthless, for example.

That’s what homeowners insurance is for.

Re: Solar panels reduced my electric bill in 2022

#230

Post by EricE » Tue, Jan 03, 2023, 7:09 PM UTC

malfist wrote: post #54

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…

Perhaps instead of being angry that people are using taxes that come from the working class, instead you should ask why the wealthy aren't paying their share of the taxes? And nobody pays for anything with inflation. That's not how inflation works.

"And nobody pays for anything with inflation."

other than inflation canceling the debt of the rich/government by moving to all of us.