Sure but if we succeed at mitigating cimate change effects to a reasonable degree, civilization will survive for centuries, during which a reactor that uses itmight become available. It’s a minor problem blown out of proportion, as opposed to CO₂ emissions, which are the opposite.
Even if this were true this doesn’t help with the very real issue that we can’t build the nuclear capacity fast enough whereas renewable energy can be built fast, is already being built, and doesn’t have that problem that needs wishful thinking for it’s solution.
Because batteries aren’t as dangerous as reactors, are still making massive improvements on energy density and seem feasible to me. Doing anything useful with nuclear waste has been discussed for decades and no-one has come forward with any really promising results. The waste has been around for long enough if anyone could have done something productive with it it likely would have happened already.
It’s just an example number. No matter what if you are building a grid that has 0 baseload power generation, you need some amount of storage capacity for each KWh of consumption. We can argue how much you actually need, but the fact remains that when you start storing large amounts of power, which you would need in-order to keep a city running during times of reduced generation, it takes a large amount of space.
In order to demonstrate that, I chose a pretty straight-forward scenario of a city of 1million for just one day. Let’s assume that this amount of stored energy would be sufficient for a 100% renewable grid for say New York City.
So how much energy storage would be needed and how much space would such a storage facility take up?
For the fun of it I did do the calculation. Berlin uses about 12TWh per year. That’s about 33GWh per day.
Assuming an energy density of 450Wh/l (a number car batteries apparently were able to reach 2020) that’s about 80.000 m³.
A soccer field is about 4000 m². So a space of 10 soccer fields with 20m high battery stacks would do that.
Now assume that energy density will have improved in the last 4,5 years and that maybe storage batteries can be different from batteries in cars and that can go down by a lot. Seems reasonable enough for the biggest city in Germany.
That is a currently realized grid storage facility, the largest and really only one of it’s kind. Today’s renewables do not do storage at all, they rely on fossil fuels to make up the baseload.
Some numbers. This facility stores 1400MWh, on 2,000 acres or (~8,000,000 sq meters) Much greater then your 40,000sq meter estimate. Plus you said about 33GWh for a day. Well you’d need ~24 of these facilities to cover just Berlin.
Yes it wouldn’t have to be monolithic like that facility is, but regardless of how you distribute it, it’s a non-trivial amount of space taken up. Totally ignoring the costs, and sourcing the materials for the batteries of such facilities.
But just for fun that facility was ~$550M So you’d need to spend about $2.3T for the initial building of that storage.
The premise of powering a complete city just from one singular facility is a false one. It’s unnecessary to build such a facility. You can build multiple smaller ones to supply sectors of a city according to the needs of that sector. The answer also depends on how smart the usage of the power is. Are people using power when it’s available? Are people trying to use a lot of power when it’s not available but must come from storage? There are so many factors your scenario doesn’t take into account. The answer has to be: it depends.
This also feels a lot like a gotcha question not posed in good faith. Because again: you won’t need to power anything solely from storage. Wind and sun will always supply a base level of energy.
Wind and sun will always supply a base level of energy.
That is objectively false. The sun doesn’t shine at night, and wind doesn’t blow 100% of the time. So logically there is some amount of time that you do not get a base load provided only by sun and wind. Hence the need for storage at all. And yes it is a gotcha question, because it’s something that anti-nuclear people hand-wave away as if the significant storage infrastructure to support a 100% renewable is just a rounding error, and not worth thinking about.
Sure but if we succeed at mitigating cimate change effects to a reasonable degree, civilization will survive for centuries, during which a reactor that uses itmight become available. It’s a minor problem blown out of proportion, as opposed to CO₂ emissions, which are the opposite.
Even if this were true this doesn’t help with the very real issue that we can’t build the nuclear capacity fast enough whereas renewable energy can be built fast, is already being built, and doesn’t have that problem that needs wishful thinking for it’s solution.
Why do you not include city-scale energy storage as wishful thinking? Unlike nuclear reactors, that amount of storage doesn’t exist.
Because batteries aren’t as dangerous as reactors, are still making massive improvements on energy density and seem feasible to me. Doing anything useful with nuclear waste has been discussed for decades and no-one has come forward with any really promising results. The waste has been around for long enough if anyone could have done something productive with it it likely would have happened already.
How big would a battery need to be to power a single city of 1000000 for 1day?
Why would you want to do that? Do you fear that there might be absolutely pitch black days with absolutely zero wind?
It’s just an example number. No matter what if you are building a grid that has 0 baseload power generation, you need some amount of storage capacity for each KWh of consumption. We can argue how much you actually need, but the fact remains that when you start storing large amounts of power, which you would need in-order to keep a city running during times of reduced generation, it takes a large amount of space.
In order to demonstrate that, I chose a pretty straight-forward scenario of a city of 1million for just one day. Let’s assume that this amount of stored energy would be sufficient for a 100% renewable grid for say New York City.
So how much energy storage would be needed and how much space would such a storage facility take up?
For the fun of it I did do the calculation. Berlin uses about 12TWh per year. That’s about 33GWh per day.
Assuming an energy density of 450Wh/l (a number car batteries apparently were able to reach 2020) that’s about 80.000 m³.
A soccer field is about 4000 m². So a space of 10 soccer fields with 20m high battery stacks would do that.
Now assume that energy density will have improved in the last 4,5 years and that maybe storage batteries can be different from batteries in cars and that can go down by a lot. Seems reasonable enough for the biggest city in Germany.
Unfortunately your rough math misses a lot of the picture. This is where the gotcha comes in.
https://electrek.co/2022/10/19/the-worlds-largest-single-phase-battery-is-now-up-and-running/
That is a currently realized grid storage facility, the largest and really only one of it’s kind. Today’s renewables do not do storage at all, they rely on fossil fuels to make up the baseload.
Some numbers. This facility stores 1400MWh, on 2,000 acres or (~8,000,000 sq meters) Much greater then your 40,000sq meter estimate. Plus you said about 33GWh for a day. Well you’d need ~24 of these facilities to cover just Berlin.
So now the big question, how much energy storage will be needed in a >90% renewable grid? It’s obviously a difficult question based on a lot of factors, but one such estimate I found here: https://www.pv-magazine.com/2022/01/24/us-zero-carbon-future-would-require-6twh-of-energy-storage/ ~6TWhrs for the US or about 4300 of those facilities.
Yes it wouldn’t have to be monolithic like that facility is, but regardless of how you distribute it, it’s a non-trivial amount of space taken up. Totally ignoring the costs, and sourcing the materials for the batteries of such facilities.
But just for fun that facility was ~$550M So you’d need to spend about $2.3T for the initial building of that storage.
The premise of powering a complete city just from one singular facility is a false one. It’s unnecessary to build such a facility. You can build multiple smaller ones to supply sectors of a city according to the needs of that sector. The answer also depends on how smart the usage of the power is. Are people using power when it’s available? Are people trying to use a lot of power when it’s not available but must come from storage? There are so many factors your scenario doesn’t take into account. The answer has to be: it depends.
This also feels a lot like a gotcha question not posed in good faith. Because again: you won’t need to power anything solely from storage. Wind and sun will always supply a base level of energy.
That is objectively false. The sun doesn’t shine at night, and wind doesn’t blow 100% of the time. So logically there is some amount of time that you do not get a base load provided only by sun and wind. Hence the need for storage at all. And yes it is a gotcha question, because it’s something that anti-nuclear people hand-wave away as if the significant storage infrastructure to support a 100% renewable is just a rounding error, and not worth thinking about.