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For Germany: "Der Anteil der Wasserkraft an der Stromerzeugung aus erneuerbaren Energien ist über die Jahre gesunken und liegt gegenwärtig noch bei ca. 8 Proze

For Germany: "Der Anteil der Wasserkraft an der Stromerzeugung aus erneuerbaren Energien ist über die Jahre gesunken und liegt gegenwärtig noch bei ca. 8 Prozent. Dieser Anteil wird in Zukunft weiter sinken, da die Potenziale der Wasserkraftnutzung in Deutschland weitgehend erschlossen sind..." The situation is similar in most of the developed world. > Your comments about intermittency are demonstrated to be wrong by detailed modeling Actually: they are not. All the detailed models show this exact problem, such as the paper I linked. > The "insane" comment is just a handwave. No, the "insane" comment is exactly the conclusion of the people who do the detailed modeling. As this paper (and many others) show, renewables are great as long as they are used for part of energy production. Trying for 100% renewables is the part that's insane. I recently had a close look at one of the "studies" by Fraunhofer that are frequently touted by renewable advocates as showing how feasible 100% renewables are. I can't imagine they actually read the study. For Germany, they say we need 750 GW of Wind/Solar + 500 GWh of batteries + 150 GW of gas plants + the electrolysers to produce the gas. In addition they also assume a massive increase in efficiency and thus reduction in consumption. Our current electricity generation needs are around 70 GW. OK, some of that is for electrification of other sectors, but for that they also assume massive synergy effects. This is fantasy-land material that makes the Brexiteer visions of "sunny uplands" appear to be voices of restraint and reason.

pfdietz 2y ago
> "The share of hydropower in electricity generation from renewable energies has fallen over the years and is currently still around 8 percent. This proportion will continue to fall in the future, as the potential for hydropower use in Germany has been largely exploited..." That's primary hydro. As I already told you, that's not pumped hydro. You don't seem to be understanding this point, so let me explain in more detail. Primary hydro involves exploiting natural water flows, extracting energy from water that falls at higher elevations as it flows down to lower elevations. It is limited by these natural water flows, and the need to be on the rivers in which the water is flowing. Pumped hydro, on the other hand, creates its own water flow. It does not need to exploit natural precipitation. It can recycle the water it uses, getting much more energy flow per unit of water (until the water seeps or evaporates away, but that is slow.) It can be placed in locations that aren't on rivers. As an example, consider this PHES project in an arid part of the Great Basin in Nevada: https://www.whitepinepumpedstorage.com/ https://www.whitepinepumpedstorage.com/ Notice the graphics with two reservoirs, constructed on flat areas by surrounding them with earthen walls, sitting in the middle of a desert without any permanent rivers in sight. The potential for this sort of pumped hydro is enormous anywhere there is sufficient vertical relief. In Australia, for example, the potential is some 100x what would be needed for a 100% RE grid. They've built a global PHES geographical database for finding places around the world (where they have data; Russia is excluded for example). http://re100.eng.anu.edu.au/global/ http://re100.eng.anu.edu.au/global/ Go play with this; the opportunities are vast. PHES is not suitable for flat terrain, so it can't be a complete solution in general, but to call it maxed out is very wrong. > Actually: they are not. All the detailed models show this exact problem, such as the paper I linked. Let's look at a review paper. https://ieeexplore.ieee.org/document/9837910 https://ieeexplore.ieee.org/document/9837910 "With every iteration in the research and with every technological breakthrough in these areas, 100% RE systems become increasingly viable. Even former critics must admit that adding e-fuels through PtX makes 100% RE possible at costs similar to fossil fuels. These critics are still questioning whether 100% RE is the cheapest solution but no longer claim it would be unfeasible or prohibitively expensive." > For Germany, they say we need 750 GW of Wind/Solar + 500 GWh of batteries + 150 GW of gas plants + the electrolysers to produce the gas. In addition they also assume a massive increase in efficiency and thus reduction in consumption. Battery storage is approaching $100/kWh (not cells, the whole turnkey system) in China now. So, 500 GWh would be $50B. If the batteries have a lifespan of 20 years that's $2.5B/year (+ interest). Can you not afford this? That's less than half of what Germany spends on pizza. Also, consider how many GWh of storage in cars would be needed if all the cars in Germany were BEVs (I get about 3 TWh).
- mpweiher 2y ago
  > As I already told you, that's not pumped hydro. Yes, you made that claim. However, it's not true. The page is about all hydro in Germany. https://www.umweltbundesamt.de/themen/klima-energie/erneuerbare-energien/nutzung-der-wasserkraft https://www.umweltbundesamt.de/themen/klima-energie/erneuerb... You also need geography for pumped hydro. Somewhere to pump the water to. > Battery storage is approaching $100/kWh "Approaching". A Tesla Megapack is more than 3x that. It's funny how EE fanboys just extrapolate trends into the future. At the rate nuclear power plants were getting cheaper they'd be free now. Well, had we not stopped building them. ¯\_(ツ)_/¯ Of course, this is very little battery, because that particular Fraunhofer study did most of the backup using gas. With 150 GW of gas fired plants. 150 GW. Let that sink in. That's more than double the current total demand. Just for backup of the 750 GW of intermittent generators. No wonder that scenario doesn't need all that much battery. Now add the cost of the electroylysers needed to create all that gas. https://taz.de/Wasserstoffprojekt-abgebrochen/!5974569/ https://taz.de/Wasserstoffprojekt-abgebrochen/!5974569/
  - pfdietz 2y ago
    Read it again. The limits it discusses are on hydro generation, not hydro storage. > "Approaching". A Tesla Megapack is more than 3x that. If your argument depends on selecting expensive rather than cheap versions of a technology, I'll do the same with nuclear. Let's use the most disastrous expensive nuclear efforts as representative, shall we? Or, we could just acknowledge that once a lower price point has been demonstrated for storage, the market will move in that direction. Storage, unlike nuclear, doesn't experience out of the blue cost escalation, and many forms are easily shipped worldwide. > Of course, this is very little battery, because that particular Fraunhofer study did most of the backup using gas. With 150 GW of gas fired plants. > That's more than double the current total demand. The gas generators would not run in baseload mode; they'd be for seasonal and Dunkelflaute coverage. Most energy from the renewables would go either directly to the grid or through batteries and then to the grid. The fraction into gas would be modest. BTW, simple cycle gas turbine + generator is about 1/20th the capital cost of a nuclear plant per unit power (combined cycle, 1/10th). So 150 GW is not nearly as much as you might imagine.

pfdietz 2y ago

> "The share of hydropower in electricity generation from renewable energies has fallen over the years and is currently still around 8 percent. This proportion will continue to fall in the future, as the potential for hydropower use in Germany has been largely exploited..." That's primary hydro. As I already told you, that's not pumped hydro. You don't seem to be understanding this point, so let me explain in more detail. Primary hydro involves exploiting natural water flows, extracting energy from water that falls at higher elevations as it flows down to lower elevations. It is limited by these natural water flows, and the need to be on the rivers in which the water is flowing. Pumped hydro, on the other hand, creates its own water flow. It does not need to exploit natural precipitation. It can recycle the water it uses, getting much more energy flow per unit of water (until the water seeps or evaporates away, but that is slow.) It can be placed in locations that aren't on rivers. As an example, consider this PHES project in an arid part of the Great Basin in Nevada: https://www.whitepinepumpedstorage.com/ https://www.whitepinepumpedstorage.com/ Notice the graphics with two reservoirs, constructed on flat areas by surrounding them with earthen walls, sitting in the middle of a desert without any permanent rivers in sight. The potential for this sort of pumped hydro is enormous anywhere there is sufficient vertical relief. In Australia, for example, the potential is some 100x what would be needed for a 100% RE grid. They've built a global PHES geographical database for finding places around the world (where they have data; Russia is excluded for example). http://re100.eng.anu.edu.au/global/ http://re100.eng.anu.edu.au/global/ Go play with this; the opportunities are vast. PHES is not suitable for flat terrain, so it can't be a complete solution in general, but to call it maxed out is very wrong. > Actually: they are not. All the detailed models show this exact problem, such as the paper I linked. Let's look at a review paper. https://ieeexplore.ieee.org/document/9837910 https://ieeexplore.ieee.org/document/9837910 "With every iteration in the research and with every technological breakthrough in these areas, 100% RE systems become increasingly viable. Even former critics must admit that adding e-fuels through PtX makes 100% RE possible at costs similar to fossil fuels. These critics are still questioning whether 100% RE is the cheapest solution but no longer claim it would be unfeasible or prohibitively expensive." > For Germany, they say we need 750 GW of Wind/Solar + 500 GWh of batteries + 150 GW of gas plants + the electrolysers to produce the gas. In addition they also assume a massive increase in efficiency and thus reduction in consumption. Battery storage is approaching $100/kWh (not cells, the whole turnkey system) in China now. So, 500 GWh would be $50B. If the batteries have a lifespan of 20 years that's $2.5B/year (+ interest). Can you not afford this? That's less than half of what Germany spends on pizza. Also, consider how many GWh of storage in cars would be needed if all the cars in Germany were BEVs (I get about 3 TWh).

mpweiher 2y ago
> As I already told you, that's not pumped hydro. Yes, you made that claim. However, it's not true. The page is about all hydro in Germany. https://www.umweltbundesamt.de/themen/klima-energie/erneuerbare-energien/nutzung-der-wasserkraft https://www.umweltbundesamt.de/themen/klima-energie/erneuerb... You also need geography for pumped hydro. Somewhere to pump the water to. > Battery storage is approaching $100/kWh "Approaching". A Tesla Megapack is more than 3x that. It's funny how EE fanboys just extrapolate trends into the future. At the rate nuclear power plants were getting cheaper they'd be free now. Well, had we not stopped building them. ¯\_(ツ)_/¯ Of course, this is very little battery, because that particular Fraunhofer study did most of the backup using gas. With 150 GW of gas fired plants. 150 GW. Let that sink in. That's more than double the current total demand. Just for backup of the 750 GW of intermittent generators. No wonder that scenario doesn't need all that much battery. Now add the cost of the electroylysers needed to create all that gas. https://taz.de/Wasserstoffprojekt-abgebrochen/!5974569/ https://taz.de/Wasserstoffprojekt-abgebrochen/!5974569/
- pfdietz 2y ago
  Read it again. The limits it discusses are on hydro generation, not hydro storage. > "Approaching". A Tesla Megapack is more than 3x that. If your argument depends on selecting expensive rather than cheap versions of a technology, I'll do the same with nuclear. Let's use the most disastrous expensive nuclear efforts as representative, shall we? Or, we could just acknowledge that once a lower price point has been demonstrated for storage, the market will move in that direction. Storage, unlike nuclear, doesn't experience out of the blue cost escalation, and many forms are easily shipped worldwide. > Of course, this is very little battery, because that particular Fraunhofer study did most of the backup using gas. With 150 GW of gas fired plants. > That's more than double the current total demand. The gas generators would not run in baseload mode; they'd be for seasonal and Dunkelflaute coverage. Most energy from the renewables would go either directly to the grid or through batteries and then to the grid. The fraction into gas would be modest. BTW, simple cycle gas turbine + generator is about 1/20th the capital cost of a nuclear plant per unit power (combined cycle, 1/10th). So 150 GW is not nearly as much as you might imagine.