Live data from Hacker News

Solar panels reduced my electric bill in 2022

mattbruenig.com

481–490 of 510 posts

Re: Solar panels reduced my electric bill in 2022

#481

Earlier quoted context omitted.

There is typically a ten year warranty on the installation that covers leaks. An installer checks for roof age as part of qualification so you don't put panels on a roof that will age out before the panel warranty (typically 20 years, sometimes 25.) Roof leaks that are accidental are covered by insurance, and the work to remove or replace the panels is part of that. Typically you adjust your home insurance coverage b…

I don’t use any numbers. Just wanted to point out there is slightly more to it than the upfront cost. As with anything there is an associated maintenance cost that is variable depending on circumstance. To be clear I think solar panels can be a great idea, but it’s misleading to present only a single upfront cost when determining the years to break even

I understand. It's not bad to keep in mind (I made a spreadsheet with anticipated expenses before I got my panels), but I think it can be more misleading to dwell on small risks than not to if it keeps someone from buying an asset with a good lifetime ROI for most people.

Re: Solar panels reduced my electric bill in 2022

#482

Earlier quoted context omitted.

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?

A lease just doesn't make financial sense for a long-term (likely permanent) asset.

Re: Solar panels reduced my electric bill in 2022

#483

Earlier quoted context omitted.

My brother-in-law's panels produce just as much electricity at noon in the winter time as they do in the summer time. Winter sun in the Canadian prairies is quite intense, and the panels are more efficient at -20C than they are at +20C.

sure but the sun is going down at 3pm, canada gets 1.5 hours of peak sunlight at best in the winter… on a lot of houses the cost of removing the snow is more than what’s gained during the short daily window of direct sunlight… eventually the sun solves the problem for free :)

Keeping those panels clear is saving him almost $100/month.

Re: Solar panels reduced my electric bill in 2022

#484
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?

It's not hard. There is type of inverters that called "Hybrid inverter", I have one that can keep power off-grid or on-grid or even on-grid in import mode only (so only import any needed power without exporting...), and it can work off-grid even without battery (from solar) but that is not recommended unless you know that your load is much smaller than the solar output, even small lead-acid battery can mitigate this issue. The way the inverter work is that when the grid goes off it will automatically switch the power export off and keep the load running from solar and/or battery in isolated mode.

Re: Solar panels reduced my electric bill in 2022

#485
post #436
post #405

Earlier quoted context omitted.

Oh fun! I love when people Dunning-Kruger themselves on accounting (I literally just sat up straight in my chair!) Let's go through your argument (would you believe I did both read and understand the document I linked!?), but before we do that, let's look at some more traditional subsidies that O&G gets in America: [0] The GAO has reported extensively that taxpayers have not received a fair rate of return due to outd…

>Underpriced use of public land sure sounds like a subsidy to me! I have no problem with raising lease rates for Federal land to market rates. >>US gas is cheaper than elsewhere in the developed world because a) the US is self-sufficient in terms of supply >Oh, I was unaware that the cheap gas phenomenon started in 2008 when we started approaching energy independence. Thanks Obama, I guess. Oh, come now. It is a fact…

>I have no problem with raising lease rates for Federal land to market rates.

I don't care what your opinion is. Again, just pointing out that it is a subsidy.

>Oh, come now. It is a fact that, both historically and today, part (not all, but part) of the reason why US gas prices are lower than in the rest of the developed world is because the US is relatively self-sufficient.

That's simply not true! 2008 was the beginning of the trend toward energy self sufficiency; please look at the data [0]. The US was far from self-sufficient for most of the 20th Century.

>You and I both know that when people here and on Reddit claim that "the US subsidizes gas and that's why it's so cheap", 99% of the time it's meant to convey the claim "US gas companies get zillions in handouts from the government" (in the sort of bags with dollar signs that Mayor Quimby receives his bribes in), as opposed to "gas is taxed less in the US than elsewhere" (much less "US gas isn't appropriately pricing in externalities"), and 99% of the time that's the message that's taken away by the reader.

This is hard to follow, but we do not agree there. I am just making the point that subsidies are poorly understood by you and the people on Reddit, yet no one seems to want to learn more about them.

>Your statement, however, implies that other countries' gax taxes are higher because they are more appropriately pricing said externalities. We both know that Canada or Belgium or Portugal's gax taxes are not higher than in the US because their governments have duly, nobly, and wisely calculated the impact of climate change and have set the tax rates accordingly. (Maybe Norway.) Said taxes are higher because their governments believe they are acceptable to the public, and are spent accordingly as part of general funds as opposed to being all (or even part) sent to a "global warming lockbox", or somesuch.

Again, pricing externalities does not work that way. It's not a "pay to solve the problems" thing, it's a "make the true cost apparent to the consumer" thing. Politicians often use the funds to solve the problem because that's a popular thing to do, but it's usually not the best use of funds anyway (receipts and expenditures, in general, should not be tied because then you're just randomly skewing markets rather than rationally governing).

>First, both the degree and kind matter.

Agreed, but again, what does the US Federal government receipts have to do with how much these subsidies skew the market?

>Second, EIA says (https://www.eia.gov/tools/faqs/faq.php?id=23&t=10>) that in 2021 135 billion gallons of gas were consumed in the US. We'll simplisticly say that every cent of of the $4 billion a year in "subsidies", which the EESI is presumably citing as a worst-case figure, can be assigned to gas. So each gallon is being "subsidized" by about $0.34. Not nothing (and, again, this is a worst-case figure), but relatively small versus the massive swing we saw in 2022 in the price per gallon (https://www.cnn.com/2022/12/29/energy/oil-gas-prices-2022/in...>). More importantly, said amount is absolutely not the explanation for the difference in price per gallon/liter between the US and other developed countries, either.

This is the most wildly incorrect part of your comment. Subsidies skew supply/demand curves, both of which have slopes. If it were as easy as you make it seem, we'd all be Economics PhDs.

The government does not give Exxon $0.34 per gallon it sells, it gives them incentives to do things they wouldn't otherwise do, and given supply and demand dynamics that has complex effects on the market.

And again, circling back here, all I'm trying to say is that the US meaningfully subsidizes energy, which they do. I honestly think it's a good thing! It's been the economic engine of growth for the US. I don't think we should stop! (notice how you assumed I had an agenda just by trying to state facts, maybe examine that a little...)

If you go up to my top comment, you'll see the GP was trying to imply that it's somehow unfair to subsidize solar and I was pointing out that they were ignoring all the other subsidies that we've gotten used to/take for granted.

[0]https://www.eia.gov/energyexplained/us-energy-facts/imports-...

Re: Solar panels reduced my electric bill in 2022

#486

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.

Most solar panels are angled to the South to capture the most sun. I read somewhere that fixed installations are better because:

1) The money spent on panel rotators can be invested into having more solar panels.

2) Affixed solar panels are significantly more storm and hurricane proof. If there’s one bad storm with rotating panels, your investment principal is gone.

3) Maintenance costs increase when these moving parts eventually break. Fixed panels have no moving parts.

Re: Solar panels reduced my electric bill in 2022

#488
post #99

My system generated 14.36 MWh in 2022, which comes out to roughly $4,308 USD. The ROI is about 5-6 years for the system itself. But a new roof was also in order.... so more like 10-12 years. Still a great deal if you can afford to invest for the long term. Especially with a 30 year warranty on most of the equipment.

Another way to say that is that you installed solar panels and they paid for your new roof

How does having solar affixed to your roof affect or complicate getting a new roof on your home every 10 years?

Re: Solar panels reduced my electric bill in 2022

#489

Earlier quoted context omitted.

From my read, the solar company delivered late, causing the original loan to fall through and requiring the homeowner to refinance at a higher rate. Since that delay cost money it does seem fair that the company should bear the cost.

Going from, say, 3% to 4% on a $20k 10-year loan would cost him about $1100. He squeezed them for $5k.

Interest rates increased by 4 basis points from Dec 2021 to Dec 2022.[1] So a 3% loan then would be a 7% loan now or a 5% loan then would be a 9% loan now. The starting rate would depend on your credit score or other factors.

Citation: [1] https://fred.stlouisfed.org/series/FEDFUNDSLa

Re: Solar panels reduced my electric bill in 2022

#490
post #99

Earlier quoted context omitted.

Another way to say that is that you installed solar panels and they paid for your new roof

How does having solar affixed to your roof affect or complicate getting a new roof on your home every 10 years?

Well you need to have the solar removed before you can get your roofing work done. Then re-installed afterwards. Typically roofing and solar work is very different, so two different companies involved - just makes things a little more complicated.

Most solar companies that I've spoken to won't (or will strongly recommend against) installing solar on roofs with less than 10 years of useful life remaining.

That being said, roofs typically have a 30 to 50 year lifespan. Depending on the material, location, etc. Most quality solar panels have a warrantied life of at least 25 years. So if you're like me and had an old roof, that gets replaced first before solar gets installed.

And by the time the solar panels are EOL, the roof will be close to it as well. So they'll both get replaced again. Assuming I'm still in the same house in 30 years time.

Post reply on HN