alt Hacker News> And don't let perfect be the enemy of good. Yes there are times when solar doesn't produce energy, but there are also times where it OVERproduces.
When solar OVERproduces you have to literally pay someone to consume that energy, most probably wind farms, which could be producing energy instead. So you pay actually twice. When the solar underproduces, you need to bring in alternative sources, but those now have to cover all their fixed costs and generate return on investment over this limited timeframe, which means the actual backup prices hit stratospheric levels.
What's the actual cost of solar with actual net-billing?
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This is not how curtailment works.
Curtailment is when an energy company has successfully bid on delivering electricity for the next block of time (an hour, for example) but it can’t provide that agreed amount of power because it would overload the grid. There are various reasons why that would happen: faults and unexpected lack of demand, for example. In that case the company is paid for the energy it was contracted to deliver, only for that period of time, even though it did not provide power.
It is wrong to say that overproducers HAVE to be paid. They don’t. They only have to be paid if there was an agreement to buy that power but for whatever reason the grid can’t take it. Normally if there is a generation surplus, the cheapest companies will win the bid to provide power and the others will simply not be paid.
> When solar OVERproduces you have to literally pay someone to consume that energy,
Can't we just throttle the solar panel? In a worst case, you just pull the plug. It's not like a nuclear power plant which needs to be shut down carefully, or am I misunderstanding something?
> When solar OVERproduces you have to literally pay someone to consume that energy, most probably wind farms, which could be producing energy instead.
You don't have to do this with solar, you can just disconnect the panel and have it go a bit hotter. For producers that have a long-ish bringup time, yes, you might need to do this at time.
>you have to literally pay someone to consume that energy,
Here's the thing. That's a rule and not a technical problem. Absolutely no reason to do this other than rules and regulations.
Here in Finland electricity prices can drop to under 1c/kWh due to renewables, basically every time it's sunny and/or windy electricity is practically free (the transfer costs are static though).
A few times the price has actually been negative, people got paid for using electricity due to overproduction =)
Cheap home solar installations usually have a disconnect- do they not use those in larger scale installs?
I'm also surprised they aren't using batteries to capture overproduction. They've been clutch in the US, and we're not exactly pushing the envelope of green energy nowadays
There will be connected batteries in every home solving this problem faster than the fossil fuel lobby can come up with a new talking point about why it’ll never work.
Inverters can be configured with export limits to limit, or entirely halt, energy exports based on market or grid signals. Term of art is "curtailment."
No you don’t, you could just ground it. Paying them is a choice.
When there's an OVERproduction of energy, that really means there's an UNDER-availability of storage. Battery tech continues it's march towards cheaper prices, and alternatives such as thermal storage are making inroads as well.
It borders on criminal to have abundant energy production be disservice.
"If you find dollar bills on the ground you need to pay someone to collect it as litter"
Charge batteries, do electrolysis, or a multitude of other uses (I know some companies do that already)
Home installations just cut it off. In both of these cases.
I did my own battery backed installation. When I'm underproducing I can shed load (I turn off my AC - almost always that's enough, and it's automated by relay). When I'm overproducing (ex - my battery is full and my load is still not enough to consume input) I just don't let the panels generate more current than I can consume.
Managing grid scale power is different concern, and not particularly relevant to small household generation. Especially not relevant in the 800W category for "balcony solar" (which is much smaller than what I'm working with).
Solar is fucking coming, whether you continue to shove head into the ground or not.
It's just way more affordable. Getting easily more affordable as batteries continue to improve.
I honestly doubt I'll still be connected to a local utility grid for electric 10 years from now, and I live in a region of the US that has considerably cheaper grid power than most areas.