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Well scaring people away from renewables is pretty counter-productive to the decarbonizing cause so that was not my intent. I happened upon that article when re

Well scaring people away from renewables is pretty counter-productive to the decarbonizing cause so that was not my intent. I happened upon that article when reading something else earlier today and thought it might be relevant. Certainly coal is worse. We should just be careful to not replace one problem with another. Obviously in mass, coal will dominate. It's most a question of raw material availability or economics of recycling that matter for the vast expansion of energy harvesting we're talking about here. I'm glad that you as a knowledgeable person in the topic are not concerned about any negative implications of vast renewable buildout for electricity, transport, heating, and industry.

philipkglass 8y ago
There is one important material constraint before expanding solar PV technology to the multi-terawatt scale: silver. Right now silver-containing conductive pastes are the overwhelmingly popular choice for forming cell contacts. I expect copper contacts to replace silver pastes at some point. Plated copper has higher conductivity than printed silver paste and of course the raw metal is much cheaper, but it takes more effort to integrate plating into manufacturing flows. SunPower already uses copper metallization at gigawatt scale cell production levels, so I'm pretty confident that other manufacturers can follow when silver costs go up. The one important possibly-constrained battery material is cobalt as a component of lithium-ion battery cathodes. But stationary storage batteries don't need to maximize energy density and therefore don't need to use the same cobalt-bearing cathodes as those in mobile electronics and electric vehicles. The key attribute of a stationary grid-storage battery is lifetime -- encompassing both calendar life and cycle life. Long-life batteries don't need cobalt if the energy density is negotiable. FWIW you can see from my comment history that I have no qualms about the scalability or safety of nuclear power either. I think that deep decarbonization may require additional nuclear power. The cost trajectory for storage-backed renewables just looks more promising than the cost trajectory of new nuclear power right now. It appears that the least-cost decarbonization path will emphasize renewable/storage buildout until the marginal decarbonization cost rises high enough to justify more high-cost (but rock-steady) nuclear reactors.

philipkglass 8y ago

There is one important material constraint before expanding solar PV technology to the multi-terawatt scale: silver. Right now silver-containing conductive pastes are the overwhelmingly popular choice for forming cell contacts. I expect copper contacts to replace silver pastes at some point. Plated copper has higher conductivity than printed silver paste and of course the raw metal is much cheaper, but it takes more effort to integrate plating into manufacturing flows. SunPower already uses copper metallization at gigawatt scale cell production levels, so I'm pretty confident that other manufacturers can follow when silver costs go up. The one important possibly-constrained battery material is cobalt as a component of lithium-ion battery cathodes. But stationary storage batteries don't need to maximize energy density and therefore don't need to use the same cobalt-bearing cathodes as those in mobile electronics and electric vehicles. The key attribute of a stationary grid-storage battery is lifetime -- encompassing both calendar life and cycle life. Long-life batteries don't need cobalt if the energy density is negotiable. FWIW you can see from my comment history that I have no qualms about the scalability or safety of nuclear power either. I think that deep decarbonization may require additional nuclear power. The cost trajectory for storage-backed renewables just looks more promising than the cost trajectory of new nuclear power right now. It appears that the least-cost decarbonization path will emphasize renewable/storage buildout until the marginal decarbonization cost rises high enough to justify more high-cost (but rock-steady) nuclear reactors.