this post was submitted on 31 Aug 2026
416 points (99.5% liked)
Green Energy
4568 readers
156 users here now
Everything about energy production and storage.
Related communities:
founded 4 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
We could use the excess power to bank carbon, then if we need more power we can burn that same carbon.
Edit: This isn't to be efficient, it's to remove carbon from the atmosphere and reverse global warming. I meant that being able to use it as emergency fuel would just be a perk.
Seems super complicated when you could just pump water up a hill, then open a dam when we need more power.
My bad, the carbon banking would be to clean the atmosphere, being able to burn it is just a side effect.
Have you tried boiling water?
Jokes aside:
Instead of boiling that water to run a turbine perhaps we could use a Thermal Electric Generator to extract energy without said turbine and everything that comes with it.
Dont know how well this would scale or what it's hard use limits would be. But I hear a common solution to "too much solar" is to run the excess energy into heating a pool.
A Thermo Electric Generator could allow people to recapture that energy in their pool.
Heat pumps work like this. They pump heat into the ground during hot months, then take some of it back during cold months.
Hear pumps do this, but they pump energy into the ground during hot months to cool the house, then during cold months they pull some of it back.
Pumped hydroelectric storage is really hard to do at scale, because gravitational potential energy requires a gargantuan amount of mass raised a very tall height.
A containerized battery storage system can fit up to 5 MWh of storage in a single 40-ft shipping container. 5MWh is 18 gigajoules, or 18,000,000,000 joules.
Raising 1 kg (or 1 liter of water) by 1 meter stores 9.8 joules of gravitational potential energy. So you need to scale this upwards and find 1.8 billion to fit into mass or height in order to match the storage of one measly shipping container battery system. So basically any gravity storage system needs very favorable geography, and can't really scale the way that battery storage systems can.
Right, but I was comparing pumped hydro electric to carbon capture for fuel...
I'm still hopeful for synthetic hydrocarbon production from power-to-liquid Fischer-Tropsch processes, especially the ones that convert captured CO2 and H2 into kerosene for jet fuel. That same 5 MWh/18 gigajoules of energy I was discussing in my earlier comment can be stored in about 390 kg of synthetic kerosene, at 46.4 MJ/kg.
There's no doubt that it will require a lot of technological and engineering advancement for carbon capture + hydrolysis + the whole PtL process to approach the round trip energy efficiency of charging a lithium ion battery (90%) or pumped hydro (75%), but if we do intentionally overbuild solar and run the chemical plants at near-negative energy prices based on time of day, it could lead to a more broadly sustainable global supply chain for decarbonizing existing fossil fuel systems (like airplane jet engines).