When I was in elementary school, the cafeteria switched to disposable plastic trays because the paper ones hurt trees. Stupid, I know… but are today’s initiatives any better?

  • JasSmith
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    21 year ago

    Renewables will never replace stable energy production until the storage problem as been solved. At present there are no practical mass storage solutions available. So on days when the sun doesn’t shine or the wind doesn’t blow, there isn’t sufficient energy generation without LNG/coal/nuclear. This will be true for decades. Nuclear is currently the best option of those three. Some places are lucky with hydro generation, but even this is subject to variable rainfall. Tidal generation has come a long way, but it’s still not ready for prime time, and it also suffers from variability.

      • JasSmith
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        11 year ago

        I wrote, “renewables will never replace stable energy production until the storage problem as been solved.”

        It appears you read, “renewables are currently not economically viable.”

        That’s not my argument. I didn’t write that.

        • Hugohase
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          11 year ago

          The first link about growing storage wasn’t enough?

          • JasSmith
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            1 year ago

            The storage problem is solved it’s just not necessary

            False. There is currently no technology which enables an economically viable solution for 100% renewable grids.

            Just to give you an example, Denmark’s wind generation just yesterday fluctuated 92%. Over the last year, wind generation has fluctuated across Europe by more than 555%. Europe currently produces around 6,480GWh per day. To buffer even half this during periods of low wind/low sunshine would require 60+ million Tesla batteries. For reference, Tesla has only ever produced three million batteries.

            For now, power grids require reliable generation. Unless you want coal and LNG, it has to be nuclear.

            • Hugohase
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              1 year ago

              False. There is currently no technology which enables an economically viable solution for 100% renewable grids.

              Do you have any proof of this other than your own conclusions? Because a lot of experts see this very differently.

              It seems Denmark is doing fine at the moment, so I don’t really see your argument there.

              By the way, the EU wants to develope hydrogen for long term storage.

              If you want expensive, sure you can use nuclear.

              https://www.lazard.com/research-insights/2023-levelized-cost-of-energyplus/

              • JasSmith
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                11 year ago

                Do you have any proof of this other than your own conclusions? Because a lot of experts see this very differently.

                One cannot prove a negative. Can you prove that god does not exist? Typically the burden of proof lies with the one making any positive claims such as you are.

                The report you cite doesn’t appear to indicate that batteries could smooth a fully renewable grid. Perhaps I’ve missed that important part. Would you cite the page?

                • Hugohase
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                  11 year ago

                  One cannot prove a negative. Can you prove that god does not exist? Typically the burden of proof lies with the one making any positive claims such as you are.

                  Of course it would be possible to proof that something isn’t economicly viable exept in this case, because it is.

                  Here is a model of an economicly viable stand-alone system.

                  https://www.sciencedirect.com/science/article/abs/pii/S2352152X22007836

                  The link above was about how insanely expensive Nuclear is compared to, well, everything else.

                  • JasSmith
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                    11 year ago

                    Thanks for the study. Super interesting. So they used Grand Canary Island as a proof of concept for the study. The two proposed storage mechanisms were li-ion batteries and hydro. They propose 5.82GWh, which is the equivalent of 108,000 of the cheaper 54KWh Tesla batteries. Hydro works well there because of their 2,000m elevation over a short distance. Their daily energy production is around 17.5GWh, and their proposed storage solution appears sufficient given the variability in predicted wind.

                    It looks like a good use case for this location, but I’m not convinced this can be scaled to entire continents. Let’s take Europe (because I’m familiar with the data in Europe). Much of the continent is very flat. Denmark, Southern Sweden, Netherlands, and Northern Germany, for example, cannot take advantage of hydro storage, and this comprised the largest storage component of the proposed solution. In fact, given the elevation requirements, hydro would comprise a much lower proportion of storage than batteries, if scaled across Europe.

                    This leads to the second problem. Even if we assumed all of Europe had as high an elevation gradient as the Grand Canaries, the power requirements are on a complete different scale. Using the same ratios, with 37% of storage coming from batteries, and 89% of daily storage required to smooth variance, Europe would require 106.8 million Tesla batteries. For reference, Tesla has only ever produced around three million batteries in its entire existence. In reality, Europe would require far more batteries than this, as hydro storage is not possible in many locations, and economical line transmission distances cap out at around 500km.

                    We need new battery technologies or other means of economical storage to make such a grid work in Europe. I suspect the numbers are similar in the U.S. Biomass and geothermal help close the gap, but not nearly enough.

                    For posterity, I’m not proposing that at present, renewables can’t comprise an even larger share of the existing mix. I’m arguing that renewables cannot comprise the entire mix at present.