10 ms·

Where are you getting this claim? Natural gas costs somewhere between $40 and $70 per MWh [1]. Storage costs for batteries range from $100/KWh (very optimistic)

Where are you getting this claim? Natural gas costs somewhere between $40 and $70 per MWh [1]. Storage costs for batteries range from $100/KWh (very optimistic) to $300/KWh [2]. But that's per kilowatt hours. That's $100,000 per MWh to $300,000 per MWh. Solar and wind's dispatchability remains its key weakness. Storage at anywhere near the required amounts remains a fantasy. That's why Germany and California are still burning fossil fuels for ~40% of their energy, while France's share of fossil fuel generation is under 10%. 1. https://blog.aee.net/the-numbers-are-in-and-renewables-are-winning-on-price-alone#:~:text=With%20the%20cost%20of%20coal,competitive%20resources%20in%20today's%20marketplace https://blog.aee.net/the-numbers-are-in-and-renewables-are-w.... 2. https://www.nrel.gov/docs/fy19osti/73222.pdf https://www.nrel.gov/docs/fy19osti/73222.pdf

reitzensteinm 6y ago
You can use batteries more than once! If you cycle them once per day for ten years to store solar power until night, your numbers given mean they add $30-100 per MWh to the cost of that stored power (but not daytime use). Not cheap, but in no way a "fantasy". Certainly not in a world with sane carbon pricing.
- VBprogrammer 6y ago
  So the cost of storage would exceed the cost of generating the same power via a CCGT plant?
  - reitzensteinm 6y ago
    I just took parent's numbers at face value to show how they were misinterpreting them. I haven't seen much in the way of true apples to apples comparisons. Most solar plants with storage don't have much storage. For instance I saw a link this week on HN for $30 + $15/MWh for solar + storage, but the storage was only one hour of the nameplate capacity. Based on the falling prices of batteries, I don't think it will be long before solar + storage providing power evenly over 24h (an unrealistic worst case) becomes economical. At a 30% capacity factor, assuming the batteries are charging for 8 hours and draining for 16, that plant would need 5x as much storage for a cost of $30 + $75/MWh. More realistically you'd only need 3-4x as much storage as you get small amounts of sunlight later and earlier in the day, and demand curves are not flat. Halve the price of batteries, which already happened in the 2010s, and that's looking economical even with a zero price on carbon. But most countries are pretty far from saturating solar potential, so you can still build solar without storage for a while. Once you need the battery backing, it's probably going to be cheap enough.
    - emteycz 6y ago
      Are you sure it was $15/MWh? That seems more than 1000x cheaper than state of the art batteries.
      - reitzensteinm 6y ago
        That's how much the storage added to the price of power in the bid, not the capital cost of the batteries.
        emteycz 6y ago
        Oh! Thank you.
      - teraku 6y ago
        I just checked some prices for small scale PV farms you can plant to your house. It's 16,83 euro-cent for the PV per KWH and 23,74 euro-cent for the storage. Production is 10KWH, storage is 11KWH. So if we (naively) multiply by 1000 we get 23,74€/MWh. And that is for the home market. I know battery storage doesn't scale linearly, but also if you were to build this as a highly-scaled farm, I'm sure prices would also drop as well.
        bedosh 6y ago
        23 euro cents * 1000 is 230 Euros, not 23. But that is still a factor of 1000 lower then the prices mentioned in https://www.nrel.gov/docs/fy19osti/73222.pdf https://www.nrel.gov/docs/fy19osti/73222.pdf and other web publications. Are you sure about those numbers and what kind of storage do they refer to?
    - macspoofing 6y ago
      > solar + storage providing power evenly over 24h (an unrealistic worst case) becomes economical. That's not the the worst case. Solar output varies by season. So you have to have enough storage for multiple weeks. This also means you have to greatly over-provison solar panels so that they not only provide power, but also enough to charge batteries.
- Manfredo_1 6y ago
  No, that's not this works. Batteries currently cost ~$150 to $250 per KWh. As in, if you want to store one kilowatt hour, you need to spend $150 to $250 dollars on batteries. If you want to store one megawatt hour, then that's $150,000 to $250,000 worth of batteries. Yes, you can cycle this battery multiple times. I'm not sure how you think that this somehow makes storage cheaper. The fact that you can charge a 1 KWh battery and discharge it 1,000 times doesn't magically make it a 1 MWh battery. Battery cost is measured in terms of cost of capacity, in watt hours. It absolutely is a fantasy to use this for grid storage. To put this in perspective, the US uses 11.5 TWh of electricity each day. The entire world produces 300 GWh of batteries every year. In order to achieve the 12 hours of storage for 80% renewables we'd consume global battery production for several years. To reach the 3 weeks storage for 100% renewable we'd need 805 years of the entire world's battery production at current levels. Sure, battery production is set to double over the next decade. But we're still talking centuries worth of global battery production to fulfill the storage demands of just the United States. And we're ignoring the fact that batteries wear out after a few thousand cycles. Again, the idea that batteries are going to make wind and solar feasible is a fantasy.
  - reitzensteinm 6y ago
    Parent compared the price of one MWh of power from a natural gas plant with the capital cost of building batteries that can store one MWh. This is a type error.
    - Manfredo_1 6y ago
      The enormous capital costs demonstrates how expensive it makes solar and wind in simple terms. Even if we measure in terms of cost per watt hour stored and drawn over the lifetime of the batter it's still hugely expensive. Most batteries can support 300 to 1,000 charge and discharge cycles. So in terms of overall cost of storage, that's still in the range of $200 to $700 per MWh of energy stored and drawn over the lifetime of the battery. This point is largely moot because we don't even have the manufacturing capacity to deliver the amount of batteries required. We only build 300 GWh of batteries globally each year. To reach 12 hours of storage, the US would need 6 TWh - 20 years of global production at current production rates.
choeger 6y ago
You are mixing up the price of capacity vs. the price of generating the electric energy. A battery for 100/kwh can be used several 100 to 1000s of cycles.
- Manfredo_1 6y ago
  > A battery for 100/kwh can be used several 100 to 1000s of cycles. You're making the same error as reitzensteinm. The fact that you can charge and discharge a 1 KWh battery a thousand times doesn't make it a 1 MWh battery. If the United States wants to use 80% renewables we need 12 hours of energy storage, which works out to 6 TWh. Even at a very generous cost estimate of $100/KWh, this works out to 600 billion dollars. The fact that batteries can be cycled for a few thousand cycles doesn't make this any cheaper. It just means we "only" need to spend 600 billion dollars every 5 to 10 years. And we'd still be burning fossil fuels at about 1/3rd the rate we currently do.
  - adrianN 6y ago
    You can avoid a lot of storage requirements by making your grid smarter and electrifying transportation and heating. 60% renewables are possible with hardly any storage at all, certainly less than 12 hours. Shifting demand is always cheaper than storage. Once you've electrified transportation, you have hundreds of millions of car batteries that can help out with demand spikes. That distributes the high upfront cost of battery storage somewhat. Car batteries that are no longer good for transportation can than be repurposed for grid storage, hopefully much cheaper than buying new batteries. To get to 100% renewables you most likely need chemical storage as hydrogen or methane.
    - Manfredo_1 6y ago
      Electrifying heating doesn't improve this situation, it worsens it drastically. People come back home after work and turn on the heat or AC right as the sun goes down. A big part of why renewable generation is so high in Germany is because they mostly heat their homes with gas (which emits carbon, but doesn't factor into electricity generation statistics). Using car batteries for storage doesn't solve the fundamental mismatch between the staggering amount of batteries that get produced and the amount of storage that is required. Not to mention, I'm dubious if this scheme would even work. Why would I hook my car storage up to the grid? It's going to eat away at the battery life of my car. This essentially just offloads the cost of battery storage to consumers by decreasing the battery life of their EVs due to the constant charge and discharging.

reitzensteinm 6y ago

You can use batteries more than once! If you cycle them once per day for ten years to store solar power until night, your numbers given mean they add $30-100 per MWh to the cost of that stored power (but not daytime use). Not cheap, but in no way a "fantasy". Certainly not in a world with sane carbon pricing.

VBprogrammer 6y ago
So the cost of storage would exceed the cost of generating the same power via a CCGT plant?
- reitzensteinm 6y ago
  I just took parent's numbers at face value to show how they were misinterpreting them. I haven't seen much in the way of true apples to apples comparisons. Most solar plants with storage don't have much storage. For instance I saw a link this week on HN for $30 + $15/MWh for solar + storage, but the storage was only one hour of the nameplate capacity. Based on the falling prices of batteries, I don't think it will be long before solar + storage providing power evenly over 24h (an unrealistic worst case) becomes economical. At a 30% capacity factor, assuming the batteries are charging for 8 hours and draining for 16, that plant would need 5x as much storage for a cost of $30 + $75/MWh. More realistically you'd only need 3-4x as much storage as you get small amounts of sunlight later and earlier in the day, and demand curves are not flat. Halve the price of batteries, which already happened in the 2010s, and that's looking economical even with a zero price on carbon. But most countries are pretty far from saturating solar potential, so you can still build solar without storage for a while. Once you need the battery backing, it's probably going to be cheap enough.
  - emteycz 6y ago
    Are you sure it was $15/MWh? That seems more than 1000x cheaper than state of the art batteries.
    - reitzensteinm 6y ago
      That's how much the storage added to the price of power in the bid, not the capital cost of the batteries.
      - emteycz 6y ago
        Oh! Thank you.
    - teraku 6y ago
      I just checked some prices for small scale PV farms you can plant to your house. It's 16,83 euro-cent for the PV per KWH and 23,74 euro-cent for the storage. Production is 10KWH, storage is 11KWH. So if we (naively) multiply by 1000 we get 23,74€/MWh. And that is for the home market. I know battery storage doesn't scale linearly, but also if you were to build this as a highly-scaled farm, I'm sure prices would also drop as well.
      - bedosh 6y ago
        23 euro cents * 1000 is 230 Euros, not 23. But that is still a factor of 1000 lower then the prices mentioned in https://www.nrel.gov/docs/fy19osti/73222.pdf https://www.nrel.gov/docs/fy19osti/73222.pdf and other web publications. Are you sure about those numbers and what kind of storage do they refer to?
  - macspoofing 6y ago
    > solar + storage providing power evenly over 24h (an unrealistic worst case) becomes economical. That's not the the worst case. Solar output varies by season. So you have to have enough storage for multiple weeks. This also means you have to greatly over-provison solar panels so that they not only provide power, but also enough to charge batteries.
Manfredo_1 6y ago
No, that's not this works. Batteries currently cost ~$150 to $250 per KWh. As in, if you want to store one kilowatt hour, you need to spend $150 to $250 dollars on batteries. If you want to store one megawatt hour, then that's $150,000 to $250,000 worth of batteries. Yes, you can cycle this battery multiple times. I'm not sure how you think that this somehow makes storage cheaper. The fact that you can charge a 1 KWh battery and discharge it 1,000 times doesn't magically make it a 1 MWh battery. Battery cost is measured in terms of cost of capacity, in watt hours. It absolutely is a fantasy to use this for grid storage. To put this in perspective, the US uses 11.5 TWh of electricity each day. The entire world produces 300 GWh of batteries every year. In order to achieve the 12 hours of storage for 80% renewables we'd consume global battery production for several years. To reach the 3 weeks storage for 100% renewable we'd need 805 years of the entire world's battery production at current levels. Sure, battery production is set to double over the next decade. But we're still talking centuries worth of global battery production to fulfill the storage demands of just the United States. And we're ignoring the fact that batteries wear out after a few thousand cycles. Again, the idea that batteries are going to make wind and solar feasible is a fantasy.
- reitzensteinm 6y ago
  Parent compared the price of one MWh of power from a natural gas plant with the capital cost of building batteries that can store one MWh. This is a type error.
  - Manfredo_1 6y ago
    The enormous capital costs demonstrates how expensive it makes solar and wind in simple terms. Even if we measure in terms of cost per watt hour stored and drawn over the lifetime of the batter it's still hugely expensive. Most batteries can support 300 to 1,000 charge and discharge cycles. So in terms of overall cost of storage, that's still in the range of $200 to $700 per MWh of energy stored and drawn over the lifetime of the battery. This point is largely moot because we don't even have the manufacturing capacity to deliver the amount of batteries required. We only build 300 GWh of batteries globally each year. To reach 12 hours of storage, the US would need 6 TWh - 20 years of global production at current production rates.

choeger 6y ago

You are mixing up the price of capacity vs. the price of generating the electric energy. A battery for 100/kwh can be used several 100 to 1000s of cycles.

Manfredo_1 6y ago
> A battery for 100/kwh can be used several 100 to 1000s of cycles. You're making the same error as reitzensteinm. The fact that you can charge and discharge a 1 KWh battery a thousand times doesn't make it a 1 MWh battery. If the United States wants to use 80% renewables we need 12 hours of energy storage, which works out to 6 TWh. Even at a very generous cost estimate of $100/KWh, this works out to 600 billion dollars. The fact that batteries can be cycled for a few thousand cycles doesn't make this any cheaper. It just means we "only" need to spend 600 billion dollars every 5 to 10 years. And we'd still be burning fossil fuels at about 1/3rd the rate we currently do.
- adrianN 6y ago
  You can avoid a lot of storage requirements by making your grid smarter and electrifying transportation and heating. 60% renewables are possible with hardly any storage at all, certainly less than 12 hours. Shifting demand is always cheaper than storage. Once you've electrified transportation, you have hundreds of millions of car batteries that can help out with demand spikes. That distributes the high upfront cost of battery storage somewhat. Car batteries that are no longer good for transportation can than be repurposed for grid storage, hopefully much cheaper than buying new batteries. To get to 100% renewables you most likely need chemical storage as hydrogen or methane.
  - Manfredo_1 6y ago
    Electrifying heating doesn't improve this situation, it worsens it drastically. People come back home after work and turn on the heat or AC right as the sun goes down. A big part of why renewable generation is so high in Germany is because they mostly heat their homes with gas (which emits carbon, but doesn't factor into electricity generation statistics). Using car batteries for storage doesn't solve the fundamental mismatch between the staggering amount of batteries that get produced and the amount of storage that is required. Not to mention, I'm dubious if this scheme would even work. Why would I hook my car storage up to the grid? It's going to eat away at the battery life of my car. This essentially just offloads the cost of battery storage to consumers by decreasing the battery life of their EVs due to the constant charge and discharging.