Senior Partner Arne Olson recently discussed several recent E3 projects modeling decarbonization in the Western U.S. on the Energy Tradeoffs podcast, which “features conversations with scholars and experts whose work addresses the difficult tradeoffs associated with the green energy transition.”
…[T]he good news is that we can … achieve 80% reductions below 1990 levels in something like the 2050 time frame [reliably and affordably]. But we did learn that a plan that focuses only on renewables is suboptimal. … We also learned that if you were to do a prohibition on new natural gas generation, then that would increase the cost of the electric grid while hardly doing anything to reduce carbon. … In a world in which we expect there to be lots of wind and solar available during most hours, we would expect the gas to run less and less and less of the time. … But we keep them around in emergencies.
About a similar recent California-focused study, which examined resource adequacy under long-term deep decarbonization scenarios, Arne said:
When we look at the [California decarbonization] problem from an economy-wide perspective, we typically don’t find that it makes sense to take the electric grid all the way to zero. … unless you have one of these technologies like nuclear, very long duration storage, or biomass-based gas. … 90-95% reduction in electric sector carbon emissions seems to be where the sweet spot with respect to the least-cost way to achieve economy-wide targets. What becomes the most constraining part of the year [in California] is the wintertime … A week-long cold weather snap [creates] a peak load problem. What we find is that if you have 100 GW of solar on the grid and it’s not available in the quantities it is in the summertime, that’s a pretty large hole you have to fill. That’s where we ended up with up to 35GW of firm capacity necessary.