>Until 80% the carbon optimal mix is Gas + Renewables. I don't understand what we're arguing about? All I said was that renewables (solar and wind specifically

>Until 80% the carbon optimal mix is Gas + Renewables. I don't understand what we're arguing about? All I said was that renewables (solar and wind specifically) need natural gas backup. In an ideal world where carbon emissions weren't a problem, that would be a non-issue, but we are trying to completely remove carbon emissions - so how is solar and wind actually helping? >For the last 20% you need to start producing the Gas from excess energy during times when renewables outstrip demand. This is hopeful thinking. The most efficient process for creating syngass is from fossil fuels. Syngas from renewables ... that's not technology that is currently viable, and it may never be viable. The other issue is that you need to greatly overprovision solar and wind infrastructre to generate a huge amount of excess energy to brige the intermittency gaps. I remember seeing some numbers on that, and they are astronomical. >A number of authors have mapped out different aspects of the transition towards 100% systems [3]. The big problem with these estimates is that they use 'biomass' to plug in the gaps that wind and solar have. Do you know what that means? It means burning garbage or using huge swaths of land to grow corn or soy or whatever to burn. That is the technology of the future? And even in that situation Germany can't be emission neutral until 2050 (i.e. never)!! This is the insanity I'm talking about. We're willing to destroy the environment we have to grow crops just to burn (not to feed people, and we still need to do that), just so that we don't use nuclear. Jesus. Why is Germany not following France, and increasing their nuclear infrastructure? Because insanity, that's why. Because of the cult of renewables. >Also, gas is incredibly much better for carbon footprint than coal Maybe. Natural gas is certainly efficient, though efficiency in this case is a little bit of a detriment, as more efficiency means more CO2 emissions. Ironically coal's dirty particulate emissions (the ones that kill humans) are actually good for cooling the planet by blocking or sun's rays. But yeah, overall natural gas is much more efficient and less CO2 is emitted per generated Watt, though the gains may be lost if the pipelines are not properly maintained and there is leakage. The big hope is that natural gas is a bridging fuel, but to what exactly? >But again, we already have 100% systems on islands today. What islands? We're talking about a grid for a modern, developed economy with millions (or hundreds of millions) of people and heavy industry, not some dinky little island. >Of course then we still have to face the hard problems: Industry and agriculture.... Yes. This is why I'm frustred that we're wasting our time with solar and wind and not scaling up our nuclear infrastructre. That's a low hanging fruit.