Does the goal of net zero carbon emissions imply zero reliance on carbon fuels?
Our conversations with Arne Olsen and Jesse Jenkins imply that retaining “firm” (read: traditionally-dispatchable at any time) capacity on the system makes the green transition much more affordable. Without them, one must build an enormous system to compensate for the intermittency if wind and solar.
Q1a: Does that imply continued reliance on gas-fired power with carbon capture? Some people seem certain that gas (or gas w/ “green gases”) is certain to be part of the long term future. (On green gases, see also the Todd Davidson and Frank Wolak conversation.)
It seems that an increasing percentage of the progressive left foresees a no-fossil fuels future; indeed, they see the continuing involvement of fossil fuel energy as an absurd denial of climate science.
Q1b: Given its cost and siting difficulties, could nuclear power be the firm resource that backs up the system?
Curious what others think about the role, if any, of fossil fuels in, say, 2045.
Literally speaking, I don't believe it implies zero reliance on carbon fuels. Ambitious climate protection goals will almost certainly require carbon dioxide removal. See IPCC on Mitigation Pathways Compatible with 1.5°C ("All analysed pathways limiting warming to 1.5°C with no or limited overshoot use CDR to some extent to neutralize emissions from sources for which no mitigation measures have been identified and, in most cases, also to achieve net negative emissions to return global warming to 1.5°C following a peak (high confidence)."). Even less ambitious climate protection goals will likely use some carbon dioxide removal.
So even if we insist on zero net carbon emissions, regardless of the cost, it would still be efficient to allow carbon fuels when they could pay the cost of removing the resultant carbon from the atmosphere. Carbon fuels have such high value for some applications that a significant volume could meet this test. See Heal & Schlenker, Coase, Hotelling and Pigou: The Incidence of a Carbon Tax and CO2 Emissions (showing that significant amounts of carbon fuel would still be used with $600/ton carbon penalty).