There are other gotchas like PACE loans being senior to your mortgage. So if you get a PACE loan, the loan is transferred to the person buying the home and is senior to your mortgage.
I'm also suspicious around the maintenance and longevity claims. For instance, from my experience, the energy efficient light bulbs do not live up to to their claims. I changed about half of my lightbulbs within three years and they supposedly have a 20+ year lifespan. It's fine that they don't have a crazy lifespan, but it just shows the industry is okay with outright false claims.
Overall I think the industry is so juiced by incentives and manipulated by regulations that it attracts shady players.
You can run a fridge, lights and a laptop 24.7 on about $300 of solar. You can add panels as your needs and budget increases. The biggest cost is the battery.
Besides the money issue, the biggest concern I have are balancing the batteries, getting the right inverters, keeping the panels clear and figuring out what inefficiencies are during the non-summer seasons.
My batteries have always been lead-acid, simply because L.A. is still much cheaper than Lithium and alternatives.
I've recently taken my first set of Lead-Acid batteries out of service. They powered a small fridge, etc, via 200W of solar panels for over 20 years with essentially zero maintenance, except for occasional top-up of distilled water.
Inverters were a problem at first. I had a series of Inverters die over the years, until I started buying Victron products. Have had zero problems since. Rule one, is "don't buy cheap inverters".
The best part is that secondhand solar panels are now very cheap. The reason is that Gov regulations for grid-tie prohibits the use of second-hand panels, so people doing upgrades will basically throw away their old panels.
My setup runs a conventional fridge/freezer, and a large computer which is on-line for most of the day, as well as my workshop full of electrical tools. I do have a large generator, but the only time it gets run is when I have some welding to do. I don't even gave a battery charger hooked to it.
There are so many myths about solar: Lead-Acid batteries don't last as they are destroyed by deep-cycles. Yes, but when you size the system, you should aim for a deep discharge maybe once a month. This still should result in twenty years life or so. I live in a wet and cloudy part of Australia, and this winter my batteries have never been as low as 80% capacity, and it is rare if the batteries haven't returned to 100% charge by 10:00am each day.
Probably the main problem with solar is that people are stupid. One of my neighbours installed a modest solar system, only to have it regularly fail due to low battery voltage. Long story short: The supplier fitted a Watt meter which tracked the consumption at each outlet. It showed that that the problem was in his daughter's bedroom. A quick search revealed a huge radiator under her bed that she was running each night. Problem solved.
Panel costs are accurate and the additional electronic expense is not super high. $1000 should be enough for most setups.
For most people the issue is space. This is going to be another thing where the poor are taxed. A significant amount of single family residences dropping off the grid will cause prices to go up for the people that don't have the luxury of 4000 sq ft to fill with solar panels.
Just a cursory look on Aliexpress gives $0.12wh for LiFePo4 batteries [0] [1].
Looking on Alibaba, I see some potential sellers that might get below that $0.12 but it takes looking around and potentially talking with sellers. I do think it's possible but it requires some hunting, especially in the 'consumer' quantities we're talking about (sub qty 100).
[0] https://www.aliexpress.com/item/3256803821576908.html?spm=a2...
[1] https://www.aliexpress.com/item/3256803518663847.html?spm=a2...
Not for nothing but there are solar bitcoin farms that are popping up for precisely this reason.
In the region where I live (upstate New York, USA), there are solar panel fields where just five years ago there was nothing.
Because this is not going to make all energy cheaper. It's going to massively increase the cost of "legacy" energy while making some types of energy free.
Perhaps they will use a "social" cost-sharing, or ... well I don't know, but essentially the time will come when living in the countryside will come with "free" energy (not unlimited though), and cities will come with punitively expensive energy.
As for costs, there's been concern for more than a decade about the "utility death spiral" scenario: some users disconnecting from a grid would spread the fixed costs of things like transmission and black start over a smaller number of remaining users, leading more of them to disconnect, and so on. So far it hasn't materialized anywhere, but as far as I know it could. I don't think the same scenario is likely with "legacy energy" like gasoline and natural gas, because the fixed costs are so low.
Taxation of energy is a big revenue stream for the governments. What happens when people start putting independent energy sources to power themselves and it causes significant revenue drop ? Would the government tax them for putting up solar on their property ? Couple this with electrification of transportation and you have another taxation source (fossil fuels) losing revenue. This would lead to a disruption in the social power dynamics in a country.
Yes, energy companies can invest in these too, but why would I buy from them if I have my own generation ?
The calculations I did for it in 2020 were that the payback period would be 7 years, or 6 with government incentives. That was when electricity was 15c/kWh though... if energy prices stay at the current level I will break even in less than 4 years. I generate around 8000kWh a year, which at current prices is €3200.
The panels should last forever (assuming no physical damage from hail storms etc), they just decrease in efficiency. The inverter should last at least 10 years, but that's easy to replace as it's not on the roof.
