5 ms·

It is not valid to compare the levelized cost of non-dispatchable sources of generation like wind and solar and dispatachable sources of generation like coal an

It is not valid to compare the levelized cost of non-dispatchable sources of generation like wind and solar and dispatachable sources of generation like coal and nuclear. It’s an apples to oranges comparison, unless you some storage costs to the wind and solar. In that study you see there is overlap between coal and PV systems and batteries.

ben_w 4y ago
Only for rooftop batteries. The estimate for utility scale batteries is entirely lower than coal.
- brnt 4y ago
  Afaik thats one of the challenges: there is no such thing as utility scale batteries. Nothing that stores a summers worth of PV and releases it in winter.
  - ben_w 4y ago
    That’s kinda why Tesla is doing what it’s doing. I’m not sure the exact production, but it looks like nearly 4 GWh in fixed storage last year, and at least 50 GWh (0.93 megacars * 54 kWh smallest battery) in their cars required the ability to rapidly make factories that can make batteries that could also be used in grid storage (I’m assuming making the batteries is the hard part of both electric cars and grid storage, if I’m wrong about that it breaks my argument). (And inter-season storage is too high a threshold: not many people are living in the artic/antarctic circles away from grids connecting them to places that still get some sun even in winter).
    - brnt 4y ago
      Its a decent effort, but to put 4GWh in perspective: my small house requires about 10MWh in heating over the winter. I can reduce that with a heat pump by a factor 4, but that till means the storage is only enough for about 1800 homes. We need a PWh+ of storage, and we need it in the next decade, and we are nowhere near on schedule.
      - ben_w 4y ago
        Very few people need seasonal storage, most people are on a grid connected to somewhere closer to the equator: https://en.wikipedia.org/wiki/Wide_area_synchronous_grid https://en.wikipedia.org/wiki/Wide_area_synchronous_grid
        brnt 4y ago
        All of Europese, far starters.
- belorn 4y ago
  A few weeks ago there was a link paper by an green energy investment advisor firm posted on HN. It displayed the economics pretty clear. Depending on location, a battery with capacity up to 6 hours can be economical viable as long they get a full discharge (ie they sell all the energy) each day at peak price and can charge when the price is at the bottom. It depend in location, how big the difference is between bottom and peak price, and how long that the price sits at each price point. For wind all those assumptions are wrong and thus won't work. You do not get a daily discharge where you can sell all the energy, you don't get a significant price change each day where you can utilize the price difference, and the capacity needed is a few orders of magnitude greater. Green hydrogen is one of the bigger bets people are hoping on, and right now it only cost several times more than nuclear. Except rather than using nuclear countries are burning fossil fuels because that is cheaper, and thus coal.
  - ben_w 4y ago
    (Wind + batteries) wasn’t something I saw in what I linked to, so in this sub-thread I’m focussed on (PV + batteries) even though the link said the LCOE of onshore wind (by itself) was lower than that of coal.
ZeroGravitas 4y ago
Or you sell the excess power to other countries like France does with excess nuclear. I wonder how much their power would cost if they were forced (for no reason at all) to store all that excess nuclear power and use it themselves rather than sell it to willing buyers. It would make nuclear look really uneconomic. Even more so than it already is.
olddustytrail 4y ago
Neither coal nor nuclear are dispatchable. Dispatchable means you can turn them on and off on demand. So grid storage batteries, hydro and gas turbine (in order of fastest to slowest).

ben_w 4y ago

Only for rooftop batteries. The estimate for utility scale batteries is entirely lower than coal.

brnt 4y ago
Afaik thats one of the challenges: there is no such thing as utility scale batteries. Nothing that stores a summers worth of PV and releases it in winter.
- ben_w 4y ago
  That’s kinda why Tesla is doing what it’s doing. I’m not sure the exact production, but it looks like nearly 4 GWh in fixed storage last year, and at least 50 GWh (0.93 megacars * 54 kWh smallest battery) in their cars required the ability to rapidly make factories that can make batteries that could also be used in grid storage (I’m assuming making the batteries is the hard part of both electric cars and grid storage, if I’m wrong about that it breaks my argument). (And inter-season storage is too high a threshold: not many people are living in the artic/antarctic circles away from grids connecting them to places that still get some sun even in winter).
  - brnt 4y ago
    Its a decent effort, but to put 4GWh in perspective: my small house requires about 10MWh in heating over the winter. I can reduce that with a heat pump by a factor 4, but that till means the storage is only enough for about 1800 homes. We need a PWh+ of storage, and we need it in the next decade, and we are nowhere near on schedule.
    - ben_w 4y ago
      Very few people need seasonal storage, most people are on a grid connected to somewhere closer to the equator: https://en.wikipedia.org/wiki/Wide_area_synchronous_grid https://en.wikipedia.org/wiki/Wide_area_synchronous_grid
      - brnt 4y ago
        All of Europese, far starters.
belorn 4y ago
A few weeks ago there was a link paper by an green energy investment advisor firm posted on HN. It displayed the economics pretty clear. Depending on location, a battery with capacity up to 6 hours can be economical viable as long they get a full discharge (ie they sell all the energy) each day at peak price and can charge when the price is at the bottom. It depend in location, how big the difference is between bottom and peak price, and how long that the price sits at each price point. For wind all those assumptions are wrong and thus won't work. You do not get a daily discharge where you can sell all the energy, you don't get a significant price change each day where you can utilize the price difference, and the capacity needed is a few orders of magnitude greater. Green hydrogen is one of the bigger bets people are hoping on, and right now it only cost several times more than nuclear. Except rather than using nuclear countries are burning fossil fuels because that is cheaper, and thus coal.
- ben_w 4y ago
  (Wind + batteries) wasn’t something I saw in what I linked to, so in this sub-thread I’m focussed on (PV + batteries) even though the link said the LCOE of onshore wind (by itself) was lower than that of coal.

ZeroGravitas 4y ago

Or you sell the excess power to other countries like France does with excess nuclear. I wonder how much their power would cost if they were forced (for no reason at all) to store all that excess nuclear power and use it themselves rather than sell it to willing buyers. It would make nuclear look really uneconomic. Even more so than it already is.

olddustytrail 4y ago

Neither coal nor nuclear are dispatchable. Dispatchable means you can turn them on and off on demand. So grid storage batteries, hydro and gas turbine (in order of fastest to slowest).