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I'm completely ignorant about this field, but I've heard Bill Gates and others say there are many problems with clean energy, such as land-efficiency (particula

I'm completely ignorant about this field, but I've heard Bill Gates and others say there are many problems with clean energy, such as land-efficiency (particularly in the case of solar), of course storage, etc. What might be some counterpoints to these objections?

zanny 8y ago
Storage at nation-state levels is largely solved by pump-storage hydro[1]. Yes, its expensive, especially if you lack natural reservoirs to convert into pump basins, but the economics of it are well known, the technology is mature, and implementations already exist. The real barrier is the chicken and egg problem that until there is urgent need for such storage it won't be built and building it will be time consuming and centralized-cost expensive to do. [1] https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
- kristianp 8y ago
  That's only where a mountainous area is close enough. There are limits to how far transmission losses allow you to go.
  - cesarb 8y ago
    > There are limits to how far transmission losses allow you to go. These limits are higher than you might think. The currently longest HVDC link in Brazil (https://en.wikipedia.org/wiki/Rio_Madeira_HVDC_system https://en.wikipedia.org/wiki/Rio_Madeira_HVDC_system) is 2300 km; there is another one being built that will be over 2500 km. For comparison, a quick web search tells me that the "width" of the USA (from the east coast to the west coast) is only 4500 km.
aidenn0 8y ago
For the US, at least, land efficiency is not a huge deal since the places with greatest solar intensities are largely also the areas with the fewest other uses (i.e. desert). For most other countries it's a much harder problem. Northern africa may be fairly close geographically to Europe, but the political climate is such that Europe probably won't want to rely on power coming from Africa. What seems to make the most sense currently as far as solar goes for places that don't have cheap sunny land is distributed PV plus large scale concentrated solar. CSP is about twice the power density of traditional PV in terms of land use, but typically requires a much higher capex. If battery storage continues to improve at the rate it has for the past 10 years, the storage problem will solve itself fairly quickly, though the economics are hard to figure: if NG becomes used only for peaking, then the price of NG will probably drop substantially making the target for battery pricing much lower than todays costs of NG generation. If NG keeps being used for heating (which seems likely in the near-to-medium term in the US), then that will help to keep the costs of NG up.

zanny 8y ago

Storage at nation-state levels is largely solved by pump-storage hydro[1]. Yes, its expensive, especially if you lack natural reservoirs to convert into pump basins, but the economics of it are well known, the technology is mature, and implementations already exist. The real barrier is the chicken and egg problem that until there is urgent need for such storage it won't be built and building it will be time consuming and centralized-cost expensive to do. [1] https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...

kristianp 8y ago
That's only where a mountainous area is close enough. There are limits to how far transmission losses allow you to go.
- cesarb 8y ago
  > There are limits to how far transmission losses allow you to go. These limits are higher than you might think. The currently longest HVDC link in Brazil (https://en.wikipedia.org/wiki/Rio_Madeira_HVDC_system https://en.wikipedia.org/wiki/Rio_Madeira_HVDC_system) is 2300 km; there is another one being built that will be over 2500 km. For comparison, a quick web search tells me that the "width" of the USA (from the east coast to the west coast) is only 4500 km.

aidenn0 8y ago

For the US, at least, land efficiency is not a huge deal since the places with greatest solar intensities are largely also the areas with the fewest other uses (i.e. desert). For most other countries it's a much harder problem. Northern africa may be fairly close geographically to Europe, but the political climate is such that Europe probably won't want to rely on power coming from Africa. What seems to make the most sense currently as far as solar goes for places that don't have cheap sunny land is distributed PV plus large scale concentrated solar. CSP is about twice the power density of traditional PV in terms of land use, but typically requires a much higher capex. If battery storage continues to improve at the rate it has for the past 10 years, the storage problem will solve itself fairly quickly, though the economics are hard to figure: if NG becomes used only for peaking, then the price of NG will probably drop substantially making the target for battery pricing much lower than todays costs of NG generation. If NG keeps being used for heating (which seems likely in the near-to-medium term in the US), then that will help to keep the costs of NG up.