Comment on Anon questions our energy sector

• Blue_Morpho@lemmy.world ⁨21⁩ ⁨hours⁩ ago

  This is old news now! Here’s a link from 5 years ago. forbes.com/…/new-solar--battery-price-crushes-fos…

  This is from last year: lazard.com/…/2023-levelized-cost-of-energyplus/

  As to uptime, they have the same legal requirements as all utilities.

  I was pro nuke until finding out solar plus grid battery was cheaper.

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  • iii@mander.xyz ⁨20⁩ ⁨hours⁩ ago

    Source (1)

    Later this month the LA Board of Water and Power Commissioners is expected to approve a 25-year contract that will serve 7 percent of the city’s electricity demand at 1.997¢/kwh for solar energy and 1.3¢ for power from batteries.

    The project is 1 GW of solar, 500MW of storage. They don’t specify storage capacity (MWh). The source provides two contradicting statements towards their ability to provide stable supply: (a)

    “The solar is inherently variable, and the battery is able to take a portion of that solar from that facility, the portion that’s variable, which is usually the top tend of it, take all of that, strip that off and then store it into the battery, so the facility can provide a constant output to the grid”

    And (b)

    The Eland Project will not rid Los Angeles of natural gas, however. The city will still depend on gas and hydro to supply its overnight power.

    Source (2) researches “Levelized cost of energy”, a term they define as

    Comparative LCOE analysis for various generation technologies on a $/MWh basis, including sensitivities for U.S. federal tax subsidies, fuel prices, carbon pricing and cost of capital

    It looks at the cost of power generation. Nowhere does it state the cost of reaching 90% uptime with renewables + battery. Or 99% uptime with renewables + battery. The document doesn’t mention uptime, at all. Only generation, independant of demand.

    To the best of my understanding, these sources don’t support the claim that renewables + battery storage are costeffective technologies for a balanced electric grid.

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    • Blue_Morpho@lemmy.world ⁨17⁩ ⁨hours⁩ ago

      It looks at the cost of power generation

      Yes.

      But then you added the requirement of 90% uptime which is isn’t how a grid works. For example a coal generator only has 85% uptime yet your power isn’t out 4 hours a day every day.

      Nuclear reactors are out of service every 18-24 months for refueling. Yet you don’t lose power for days because the plant has typically two reactors and the grid is designed for those outages.

      So the only issue is cost per megawatt. You need 2 reactors for nuclear to be reliable. That’s part of the cost. You need extra bess to be reliable. That’s part of the cost.

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      • iii@mander.xyz ⁨11⁩ ⁨hours⁩ ago

        But then you added the requirement of 90% uptime which is isn’t how a grid works.

        I’m referring to the uptime of the grid. Not an individual power source.

        We’ve successfully banned fossil fuels and nuclear, as is the goal of the green parties

        How much renewable production, and bess, does one need to achieve 90% grid uptime? Or 99% grid uptime?

        If it’s just 90%, I can see solar + bess beating nuclear, price wise. If the goal instead is a reliable grid, then not.

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• mosiacmango@lemm.ee ⁨21⁩ ⁨hours⁩ ago

  Uptime is calculated by kWh, I.E How many kilowatts of power you can produce for how many hours.

  So it’s flexible. If you have 4kw of battery, you can produce 1kw for 4hrs, or 2kw for 2hrs, 4kw for 1hr, etc.

  Nuclear is steady state. If the reactor can generate 1gw, it can only generate 1gw, but for 24hrs.

  So to match a 1gw nuclear plant, you need around 12gw of of storage, and 13gw of production.

  This has come up before. See this comment where I break down the most recent utility scale nuclear and solar deployments in the US. The comentor above is right, and that doesn’t take into account huge strides in solar and battery tech we are currently making.

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  • iii@mander.xyz ⁨20⁩ ⁨hours⁩ ago

    Uptime is calculated by kWh, I.E How many kilowatts of power you can produce for how many hours.

    That’s stored energy. For example: a 5 MWh battery can provide 5 hours of power at 1MW.

    What uptime refers to is: how many hours a year, does supply match or outperform demand.

    So to match a 1gw nuclear plant, you need around 12gw of of storage, and 13gw of production.

    This is incorrect. Under the assumption that nuclear plants are steady state, (which they aren’t), to match a 1GW nuclear plant, you need a 1GW battery, with a capacity of 1GWh.

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    • mosiacmango@lemm.ee ⁨16⁩ ⁨hours⁩ ago

      My math assumes the sun shines for 12 hours/day, so you don’t need 24 hours storage since you produce power for 12 of it.

      My math is drastically off though. Assuming that 12 hours of sun, you just need 2Gw production and 12gw of battery to supply 1gw during the day of solar, and 1gw during the night of solar, to match a 1gw nuclear plants output and “storage.”

      Seeing as those recent projects put that nuclear output at 17bil dollars and a 14 year build time like, and they put the solar equivalent at roughly 14billion( 2 billion for solar and 12 billion for storage) with a 2 - 6 year build timeline, nuckear cannot complete with current solar/battery tech, much less advancing solar/battery tech.

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      • iii@mander.xyz ⁨11⁩ ⁨hours⁩ ago

        Assuming that 12 hours of sun, you just need 2Gw solar production and 12Gw of battery to supply 1Gw during the day of solar, and 1Gw during the night of solar,

        Again, I think you might not understand the difference between W and Wh. The SI unit for Wh is joules.

        When describing a battery, you need to specify both W and Wh. It makes no sense, to build a 12GW battery, if you only ever need 1GW of output.

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