I have a modest set of solar panels on an entirely ordinary house in suburban London. On average they generate about 3,800kWh per year. We also use about 3,800kWh of electricity each year. Obviously, we can't use all the power produced over summer and we need to buy power in winter. So here's my question: How big a battery would we need in order to be completely self-sufficient? Background …
I’m very ignorant on this subject, but couldn’t you just sell excess to grid and get it back for a minimal markup?
Sure, but it depends on the incentives in your country. Afaik, excess energy could be sold, but you’ll have to checkout your local incentives and energy suppliers for specifics. In most parts of Europe, the are scaling down the prices for excess energy. Therefore, battery systems are being forwarded in some cases as sort of solution for solar panels maintaining like ca. 80% +? integrity efficiency over 20 to 30 years.
For example, I read that in The Netherlands the solar panel market has crashed completely or is crashing. Note here that saturation of the market ( many existing solar panels) can also cause that.
You need to find out;
energy usage
insulation options and materials
costs /benefits
energy contracts and energy incentives.
check out current physical electricity wiring and fuses in the house
DIY or professional?
budget
etc
TLDR: dont buy solarpanels if you want to be rich. And buy them according and after you’ve done everything possible to insulate your house, whether in the colder or warmer climates. The efficiency, added value, and comfort reached by insulation outweighs everything else. Then , after doing that, check your kwh usage, and buy solars according to that.
Hope this is helpful, but seems you need to go outthere and do some exploration on the topic.
And buy them according and after you’ve done everything possible to insulate your house, whether in the colder or warmer climates.
In the USA there are silly rules that you can only get 120% capacity of your last years worth grid consumption as solar installed. So if one were to follow your advice and do all the energy efficient improvement prior to solar, then you would be restricted to getting a much smaller array. I understand why they have the rule, but its easy to circumvent by just having artificially oversized consumption for a year in your house, and you can then get the larger array you want before then doing all the energy improvements post-array installation.
Sure, but it depends on the incentives in your country. Afaik, excess energy could be sold, but you’ll have to checkout your local incentives and energy suppliers for specifics. In most parts of Europe, the are scaling down the prices for excess energy. Therefore, battery systems are being forwarded in some cases as sort of solution for solar panels maintaining like ca. 80% +? integrity efficiency over 20 to 30 years.
For example, I read that in The Netherlands the solar panel market has crashed completely or is crashing. Note here that saturation of the market ( many existing solar panels) can also cause that.
You need to find out;
TLDR: dont buy solarpanels if you want to be rich. And buy them according and after you’ve done everything possible to insulate your house, whether in the colder or warmer climates. The efficiency, added value, and comfort reached by insulation outweighs everything else. Then , after doing that, check your kwh usage, and buy solars according to that.
Hope this is helpful, but seems you need to go outthere and do some exploration on the topic.
(Ed: layout)
In the USA there are silly rules that you can only get 120% capacity of your last years worth grid consumption as solar installed. So if one were to follow your advice and do all the energy efficient improvement prior to solar, then you would be restricted to getting a much smaller array. I understand why they have the rule, but its easy to circumvent by just having artificially oversized consumption for a year in your house, and you can then get the larger array you want before then doing all the energy improvements post-array installation.
Yes , I can see how that impacts the process. indeed checking the rules and doing some prior info digging is essential.
It’s also important to check whether solar overcacity is worthwhile in the UsA. Her3 it is not( anymore).