| > PV needs physical resources that aren't for free or unlimited. PV needs space. We have about 10,000 times as much space as we need for a pure-solar economy at current power use, 1,000 times what we need if we raise everyone to the power use of the average American, but still better than 100 times what we need if we want to do that while having a 10% efficient storage system because most energy is used while the sun is up anyway. > Most energy used has still an high negative impact on the atmosphere. Yup, and will do until it’s renewable. If it was already renewable, using that power to make more renewables has no impact whatsoever. > Low efficiency somewhere is energy potentially wasted that could reduce carbon emissions somewhere else. Sure, but the ideal is a global superconducting grid, and even if you do that the easy way [0] we’re a long way from the necessary industrial base to get it done. This option is sufficiently good to be interesting in the meantime. [0] a ballistic superconductor, specifically a charged non-conductive ring in orbit. Second best option: a few square meter cross section HVDC cable encircling the planet, which needs quite a big investment in mining to get the materials for but has the advantage we can get most of it done gradually just by continuously upgrading existing grids until the very last step of crossing the Atlantic and/or Pacific. |