alt Hacker NewsIncentivizing usage during peak times makes total sense, but if price swings are this wild, how are grid scale batteries not highly economical? My rough ballpark math was that you need roughly 20 kilowatts of battery storage to make this issue basically nonexistent, and that would cost about 10 billion dollars, which doesn't seem that much for this.
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I think it's less a question of batteries being economical, and more a question of the relative economics of batteries vs solar panels.
After all, if the highest demand is between 16:30 and 19:00 you could use batteries to store power at 12:00 and sell it at 18:00 - or in famously sunny Australia you could build enough solar panels that solar output at 18:00 matches power demand.
If batteries have a solid 9% return on investment, but solar panels have an even better 12% return on investment, panels will outpace batteries even though the batteries are a decent investment.
(Also, from a politican's perspective, making batteries highly economical is how you get batteries built. And an awful lot of pro-environment policies involve raising taxes, banning things and creating new chores; it's nice to have some green policy announcements that actually benefit voters in the short term.)
One of my co-workers (I'm Australian) has 500 kilowatt-hours of storage at home...which is wild. Much more common is the 10-20 kilowatt-hours of domestic storage for a house.
They are, but they still take time to build, and loans to finance.
Here are two of SA's (which has the most renewable generation): https://en.wikipedia.org/wiki/Hornsdale_Power_Reserve https://web.archive.org/web/20220523164905/https://www.elect...
> but if price swings are this wild, how are grid scale batteries not highly economical
They are super economical in Australia and the government even offers discounts and interest free loan of 15k to buy them.
One issue with grid scale batteries is that the solar is predominantly generated in the suburbs, but the grid wasn’t built for a huge “generator” in the suburbs. It requires retrofitting the grid for this huge excess. It would be better to instead store it in the suburbs in household batteries (which they are also building out like crazy).
Yeah this is why a lot of people were thinking that the Australian opposition asking for spending $40-50 billions for nuclear that would come online in 20-30 years and to keep using coal and gas till then were being stupid.
They are, and they are being rapidly rolled out and the "post sunset" spikes are rapidly being flattened by both grid storage and "behind the meter" home batteries.
Maybe they just don't work? Otherwise someone's leaving tons of money on the table. Which implies nobody is.
They've already burned at least $15bn on that disastrous Snowy Hydro "battery" project... Could've just rolled out consumer batteries on a large scale instead.
Affordability is always relative. Australia can't afford that much battery storage, it has to spend $368bn on nuclear submarines. /s
(did you mean 20kwh per user, or 20GW overall?)
Grid scale batteries and household batteries are being widely deployed.
Australia is the third largest market in the world for grid scale batteries, and has the highest per-capita capacity in the world; https://www.pv-magazine.com/2025/10/21/australia-becomes-wor...
Not to mention more than 200k new household batteries installed in 2025 (out of roughly 10 million households).