• NekuSoul@lemmy.nekusoul.de
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    8 months ago

    We also shouldn’t just focus on generation, but also on consumption. If we had a smarter grid that could shift demand to fit the dynamic power generation of renewables better, that should reduce the required capacity for backup power generation quite a bit.

    • ThePyroPython@lemmy.world
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      8 months ago

      Base load is not the same as back up power.

      Base load is the lowest amount of power that gets used throughout the whole 24 hour period of a day, usually between 02:00 and 05:00. This usually runs hospitals, data centres and other critical infrastructure. The pick-ups during the day, peaking in the mornings, midday, and the biggest one in the evening is consumption by businesses, homes, schools, and basically everyone else.

      This increase in demand draws more power from the generation side of the grid and drags the grid frequency down (50 Hz here in the UK & Europe, 60Hz in North America).

      So the base load needs to increase output to accommodate these slower pick-ups to balance the frequency and if there is a sudden spike (like everyone boiling the kettle at halftime during a football match) then an quick response power system like hydro storage is used to quickly deliver power.

      And when demand lowers, the grid frequency increases so you need to reduce the amount of power being generated else you’ll burn out the equipment being used to transmit and distribute the power.

      Now technically it is possible to balance the grid frequency using just renewables if you have enough of them, for example you just apply the breaks on wind turbines you don’t need to generate power.

      However, and this is the kicker, peak power generation from renewables like wind and solar won’t align with the demand for the power.

      And changing people’s habits based on what power is available would be practically impossible. “Sorry lads, no football today the wind isn’t blowing fast enough”, “Sorry madam, we can’t perform an MRI today, it’s overcast and still and we’ve already used our carbon credits running the emergency coal/gas/diesel generators we have on site and we can’t spare the power” etc.

      A smarter grid helps balance the supply by better predicting the demand through data collection and work out which areas are consuming more power than others.

      If we have enough energy storage to store excess power from renewables to be used during high points during the day then great, we can do away with base load power stations.

      But all of the technologies for grid-scale power stages are still in the research and prototyping stage. And no, Lithium Ion batteries are NOT suitable for grid-scale storage because their capacity is effected too much by temperature variations and they can’t be deep cycled (fully discharged and fully recharged).

      So the result is we will need some form of base generation in the near term. This is why a lot of Europe has switched to Gas Generation. Because it produces much less pollutants than coal or oil burning (though only slightly less CO2) and they’re much quicker to build, a year or two, than traditional nuclear power stations which take about a decade.

      • NekuSoul@lemmy.nekusoul.de
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        8 months ago

        Oh yeah, I kind of skipped over that, but I actually meant that more flexible consumption helps bring down baseload demand, and in turn the need for backup generation as well once we reach that point where that matters.

        Really good explanation of the issue though. Personally, I’m a bit more optimistic about being able to be more flexible demand. Particularly EVs and heat pumps are two areas where a smart grid can help shape demand without even being noticed by the people (apart from cheaper tariffs) as long as the car is fully charged in the morning and the room temperature is maintained.

        • ThePyroPython@lemmy.world
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          8 months ago

          Those are both good points.

          Yes a smarter grid with dynamic control over high powered devices like heat pumps and EV/Hybrid Car-to-Grid chargers to actively control consumption would be a good idea.

          Heck, there’s even been trials for micro-grids with local power generation being distributed out with something called Open Energy Monitor to schedule in things like washing machines and dryers for members of the small community co-operative that run the micro grid.

          The biggest cost with EV Car-to-Grid is the cost of the vehicle and then after that, if your house / business premises is older than roughly 30 years, the power cables into the house are not rated for the power delivery and will have to be replaced.

          With heat pumps you again have the issue of the cost of the heat pump itself and the installation.

          Both are solvable but it will require large amounts of government grant money to do so.