Almost all simulations I've done across 3 countries with 3 different payback models for selling back to grid (one of the three doesn’t allow selling back almost anything above your consumption), I could never make investing in Solar not being a gamble.
You really need to gamble on odds of replacing equipment being very low for it to make sense. And in practice most people I anecdotally know that run it, after 5-7 years have already done additional purchases. The payback time keeps getting pushed back to the point that when payback will happen your panel will be worthless in efficiency compared to new ones. At industrial / commercial scale it makes sense, but humans like to move houses, and do stuff in the houses and that messes with the payback plans at the individual level.
So either I was in the wrong countries or most people just gamble on the equipment lifetime, but for that I'd rather buy SPY calls, less drama.
Outside transfer switch and a 10-20kw portable generator is like $4-5k. It requires manual switching but it works for us in our hurricane-prone region. Helped with last years 1 in a 100 year winter storm in our southern region.
Battery/solar doesn’t make sense in my opinion. Too many years to break even like this parent comment said and by the time you break even at 10 years, your system either is too inefficient or needs replacing. At least with the portable generator, you can move it with you to a new home and use it for other things like camping or RVing.
Context: I’m in the Netherlands. With taxes, power is around 25cent/kWh for me. For reference: Amsterdam is around a latitude of 52N, which is north enough that it only hits Alaska, not the US mainland.
I installed 2800Wp solar for about €2800 ($3000, payback in: 4-5 years), and a 5kWh battery for €1200 ($1300) all in. The battery has an expected payback time of just over 5 years, and I have some backup power if I need it.
I’m pretty sure about the battery payback, because I have a few years of per second consumption data in clickhouse and (very conservatively) simulated the battery. A few years ago any business case on storage was completely impossible, and now suddenly we’re here.
I could totally see this happen for the US as prices improve further, even if it’s not feasible today.
Is it priceless? I literally wouldn't pay more than $200 to have electricity for a day while the whole neighborhood doesn't. Anything more and I'd prefer to just keep the money in my pocket to be honest.
In my country I've never had to deal with more than 15 minutes, twice in my life. In other countries its sometimes been a day but really I just go on with my life.
Whats funny about that -- is you assume thats the case - but a lot of solar isn't installed to be backup power. With Storage yes, but straight up solar -> no.
99% of systems are grid tie, so unless you’re spending another $7k for an ATS and associated infrastructure or you’re 100% off grid, your power still goes off.
"An ATS (Automatic Transfer Switch) for solar is a crucial device that seamlessly switches your home's power between the utility grid, your solar panels/battery bank...
And I should clarify that you technically can get away with a less expensive interlock system, but you're still paying a few thousand dollars to have your panel replaced (unless you feel comfortable doing that sort of electrical work yourself).
Making a system non-grid-tie is comparatively expensive, that's why grid tie is so common. People think you add solar + batteries and you're ready for doomsday - not quite.
im a systems engineer and cost analyst who has put together some modeling myself as well. as a personal investment on your house, i agree. The economic value of solar seems to be best applied as neighborhood or block purchases, like as part of a co-op or hoa. they would need dedicated infrastructure like a communal parking lot with solar overhead, or running them on the property line borders with an easement underneath for servicing, using property fencing as main support (with upgraded fencing)
basically, the way it really makes sense (to me) is to integrate it as part of a micro-grid system, possibly with generator backups and everything to also keep the lights on in the entire neighborhood if the main grid goes down.
its a higher upfront cost on paper, but way less variables with the roof and you are grouping multiple peoples needs together so the gamble goes down on repairs. the poles for ground-mounting can be used for 40 - 60 years, so you would get multiple panels out of them
This is also true of heating and cooling, and I've never understood why we (in the US) build relatively dense housing communities but don't implement things like this. Having a separate air conditioner for each home, especially in a condominium/townhouse complex, has never made sense to me as it's so inefficient compared to central heating/cooling.
It could be as simple as a different model. In one of those it was easy to make it feasible if you had no cap on how much to sell back, but it was limited to consumption plus like 10% or something like that. Since the property used very little energy but had a big roof we thought itd be a good thing to produce green energy while making a little money or even just breaking even, but to break even we'd have to use way more energy which was completely against the original objective. So its not like the technology isn't able to do it but the rules can make it very hard and a few years less of operation for some components make the math very difficult if you're conservative and want to ensure break even within some reasonable timeline
You really need to gamble on odds of replacing equipment being very low for it to make sense. And in practice most people I anecdotally know that run it, after 5-7 years have already done additional purchases. The payback time keeps getting pushed back to the point that when payback will happen your panel will be worthless in efficiency compared to new ones. At industrial / commercial scale it makes sense, but humans like to move houses, and do stuff in the houses and that messes with the payback plans at the individual level.
So either I was in the wrong countries or most people just gamble on the equipment lifetime, but for that I'd rather buy SPY calls, less drama.