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I don't disagree with you—I've been to an 800 MW geothermal facility in northern California and was taken aback by the giant heaps of sulphur everywhere—but oth

I don't disagree with you—I've been to an 800 MW geothermal facility in northern California and was taken aback by the giant heaps of sulphur everywhere—but other renewables come with their own downsides. - contemporary photovoltaic panels require all sorts of strange metals to make, which have environmental impacts via mining. This might change with new materials. Solar also tends to have quite high carbon dioxide impacts due to the manufacturing process. These are obviously way less than gas or coal, but about double compared to other renewables and nuclear. - hydroelectric is notorious for destroying huge ecosystems stretching far above and far below the dam and its reservoir. Hydro is so bad that California doesn't let large projects count in the Renewable Portfolio Standard. It's tough; there's no perfect energy source.

tajen 9y ago
> Hydro is so bad that California doesn't let large projects count in the Renewable 10 cubic kilometers of water: It's the worldwide-recognized ratio under which hydro is considered renewable, and above which the ecosystem destruction is too important.
philipkglass 9y ago
...contemporary photovoltaic panels require all sorts of strange metals to make... This is not quite right. A few kinds of contemporary PV require exotic elements such as indium, gallium, and tellurium. But the market is dominated by crystalline silicon cell technology (about 93% market share in 2015): https://www.ise.fraunhofer.de/content/dam/ise/de/documents/publications/studies/Photovoltaics-Report.pdf https://www.ise.fraunhofer.de/content/dam/ise/de/documents/p...
crdoconnor 9y ago
"contemporary photovoltaic panels require all sorts of strange metals to make" Certain kinds do (e.g. CdTe and CIGS), but not the kind that you'd put on your house. If modern solar panels required significant amounts of rare earths they wouldn't be as cheap as they are. "Solar also tends to have quite high carbon dioxide impacts due to the manufacturing process." About 30g/kwh of CO2 vs. coal's ~900g/kwh, and a lot of that is simply because it is usually currently made without green power (i.e. it will go down). "It's tough; there's no perfect energy source." There's a lot of half truths told about really good energy sources.
- mrbabbage 9y ago
  Yeah, coal is obviously WAY worse than solar vis a vis carbon dioxide. I'm not disputing that. But compared to other renewables, it doesn't do as well as you'd expect: - wind: 11 g / kWh [1] - nuclear: 12 g / kWh [2] - solar PV: 45 g / kWh [3] - gas: 450 g / kWh [4] Of course, 12 g vs 45 g is NOTHING compared to 45 g vs 450 g (and coal is another 2x atop gas!), so I'm making a bit of a mountain out of a molehill. [1] http://www.nrel.gov/analysis/sustain_lca_wind.html http://www.nrel.gov/analysis/sustain_lca_wind.html [2] http://www.nrel.gov/analysis/sustain_lca_nuclear.html http://www.nrel.gov/analysis/sustain_lca_nuclear.html [3] http://www.nrel.gov/analysis/sustain_lca_pv.html http://www.nrel.gov/analysis/sustain_lca_pv.html [4] http://www.nrel.gov/analysis/sustain_lca_ngas.html http://www.nrel.gov/analysis/sustain_lca_ngas.html
  - crdoconnor 9y ago
    Gas actually contributes more to global warming even than coal does because of the methane (~100x as powerful a warming gas as CO2) also released during extraction: http://inhabitat.com/updated-cornell-study-shows-fracking-causes-more-global-warming-than-coal/ http://inhabitat.com/updated-cornell-study-shows-fracking-ca...
    - Filligree 9y ago
      On the other hand, methane breaks down fast. It's only an immediate problem; if we didn't release more CO2 than could be absorbed, then we'd have a fairly decent methane budget as well. As it stands, of course, it makes everything worse.

tajen 9y ago

> Hydro is so bad that California doesn't let large projects count in the Renewable 10 cubic kilometers of water: It's the worldwide-recognized ratio under which hydro is considered renewable, and above which the ecosystem destruction is too important.

philipkglass 9y ago

...contemporary photovoltaic panels require all sorts of strange metals to make... This is not quite right. A few kinds of contemporary PV require exotic elements such as indium, gallium, and tellurium. But the market is dominated by crystalline silicon cell technology (about 93% market share in 2015): https://www.ise.fraunhofer.de/content/dam/ise/de/documents/publications/studies/Photovoltaics-Report.pdf https://www.ise.fraunhofer.de/content/dam/ise/de/documents/p...

crdoconnor 9y ago

"contemporary photovoltaic panels require all sorts of strange metals to make" Certain kinds do (e.g. CdTe and CIGS), but not the kind that you'd put on your house. If modern solar panels required significant amounts of rare earths they wouldn't be as cheap as they are. "Solar also tends to have quite high carbon dioxide impacts due to the manufacturing process." About 30g/kwh of CO2 vs. coal's ~900g/kwh, and a lot of that is simply because it is usually currently made without green power (i.e. it will go down). "It's tough; there's no perfect energy source." There's a lot of half truths told about really good energy sources.

mrbabbage 9y ago
Yeah, coal is obviously WAY worse than solar vis a vis carbon dioxide. I'm not disputing that. But compared to other renewables, it doesn't do as well as you'd expect: - wind: 11 g / kWh [1] - nuclear: 12 g / kWh [2] - solar PV: 45 g / kWh [3] - gas: 450 g / kWh [4] Of course, 12 g vs 45 g is NOTHING compared to 45 g vs 450 g (and coal is another 2x atop gas!), so I'm making a bit of a mountain out of a molehill. [1] http://www.nrel.gov/analysis/sustain_lca_wind.html http://www.nrel.gov/analysis/sustain_lca_wind.html [2] http://www.nrel.gov/analysis/sustain_lca_nuclear.html http://www.nrel.gov/analysis/sustain_lca_nuclear.html [3] http://www.nrel.gov/analysis/sustain_lca_pv.html http://www.nrel.gov/analysis/sustain_lca_pv.html [4] http://www.nrel.gov/analysis/sustain_lca_ngas.html http://www.nrel.gov/analysis/sustain_lca_ngas.html
- crdoconnor 9y ago
  Gas actually contributes more to global warming even than coal does because of the methane (~100x as powerful a warming gas as CO2) also released during extraction: http://inhabitat.com/updated-cornell-study-shows-fracking-causes-more-global-warming-than-coal/ http://inhabitat.com/updated-cornell-study-shows-fracking-ca...
  - Filligree 9y ago
    On the other hand, methane breaks down fast. It's only an immediate problem; if we didn't release more CO2 than could be absorbed, then we'd have a fairly decent methane budget as well. As it stands, of course, it makes everything worse.