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Surplus power from renewables when supply exceeds demand. Haven’t you seen all these stories about how renewables will hit a wall because there’s not enough ene

Surplus power from renewables when supply exceeds demand. Haven’t you seen all these stories about how renewables will hit a wall because there’s not enough energy storage? Japan thinks that hydrogen is the solution for that.

kwhitefoot 8y ago
Electric vehicles are the solution. When a country has roughly half as many cars as people you have a tremendous buffer. Combine this with a grid connection to another country that has peak demand at a different time of day from your own and a lot of the problem goes away. A back of the envelope calculation might go something like this. Vehicles are idle 95% of the time on average, most countries have something like one vehicle for every two people, if all are electric and all have a 40 kWh battery (more than a original Leaf, a bit over half my Tesla S) that is on average 50% charged then in a country like Norway (roughly 5 million population) there is a storage buffer that can source or sink something like: (5e6/2) cars * (40 * 0.5) kWh capacity * 0.95 that is 47.5e6 kWh , also known as 47.5e3 MWh, or 47.5 GWh. With real time pricing and the ability to deliver current from the car as well as to it and you have pretty much solved the problem. The total installed generating capacity in Norway is just over 30 GW. If we harnessed just the batteries in the cars we already have we would have a buffer of something like 200e3 cars times 20 kWhr * 0.5 battery capacity that is about 2000 MWh, or 2 GWh. Something between one and two hours full power for the whole country. I hope I haven't got a power of ten wrong in there.
- Gibbon1 8y ago
  I think your numbers are good. Brings up a point I've seen about the difference between renewable power systems and fossil fuel based ones. Apologists for the latter will often try and impose the same reliability standards on renewables as fossil fuel systems, the day storage requirement. Then they declare renewable economically unworkable. The fallacy is fossil fuel systems are susceptible to supply disruptions. So they need to store 7 days worth of fuel to keep the thermal plants running. Less than that and they could potentially run out of fuel. Renewable's never run low on fuel due to war, accidents, and hurricanes like oil and gas does. Capacity issues (dark and stormy) is solved by long distance interties not local storage.

kwhitefoot 8y ago

Electric vehicles are the solution. When a country has roughly half as many cars as people you have a tremendous buffer. Combine this with a grid connection to another country that has peak demand at a different time of day from your own and a lot of the problem goes away. A back of the envelope calculation might go something like this. Vehicles are idle 95% of the time on average, most countries have something like one vehicle for every two people, if all are electric and all have a 40 kWh battery (more than a original Leaf, a bit over half my Tesla S) that is on average 50% charged then in a country like Norway (roughly 5 million population) there is a storage buffer that can source or sink something like: (5e6/2) cars * (40 * 0.5) kWh capacity * 0.95 that is 47.5e6 kWh , also known as 47.5e3 MWh, or 47.5 GWh. With real time pricing and the ability to deliver current from the car as well as to it and you have pretty much solved the problem. The total installed generating capacity in Norway is just over 30 GW. If we harnessed just the batteries in the cars we already have we would have a buffer of something like 200e3 cars times 20 kWhr * 0.5 battery capacity that is about 2000 MWh, or 2 GWh. Something between one and two hours full power for the whole country. I hope I haven't got a power of ten wrong in there.

Gibbon1 8y ago
I think your numbers are good. Brings up a point I've seen about the difference between renewable power systems and fossil fuel based ones. Apologists for the latter will often try and impose the same reliability standards on renewables as fossil fuel systems, the day storage requirement. Then they declare renewable economically unworkable. The fallacy is fossil fuel systems are susceptible to supply disruptions. So they need to store 7 days worth of fuel to keep the thermal plants running. Less than that and they could potentially run out of fuel. Renewable's never run low on fuel due to war, accidents, and hurricanes like oil and gas does. Capacity issues (dark and stormy) is solved by long distance interties not local storage.