The United States Can Keep The Grid Stable At Low Cost With 100% Clean, Renewable Energy In All Sectors Despite Inaccurate Claims

The premise and all error claims by Clack et al. (1) in PNAS, about Jacobson et al.’s (2) report, are demonstrably false. We reaffirm Jacobson et al.’s conclusions. Clack et al.’s (1) premise that deep decarbonization studies conclude that using nuclear, carbon capture and storage (CCS), and bioenergy reduces costs relative to “other pathways,” such as Jacobson et al.’s (2) 100% pathway, is false. First Clack et al. (1) imply that Jacobson et al.’s (2) report is an outlier for excluding nuclear and CCS. To the contrary, Jacobson et al. are in the mainstream, as grid stability studies finding low-cost up-to-100% clean, renewable solutions without nuclear or CCS are the majority (3⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓–16). Second, the Intergovernmental Panel on Climate Change (IPCC) (17) contradicts Clack et al.’s (1) claim that including nuclear or CCS reduces costs (7.6.1.1): “…high shares of variable RE [renewable energy] power…may not be ideally complemented by nuclear, CCS,...” and (7.8.2) “Without support from governments, investments in new nuclear power plants are currently generally not economically attractive within liberalized markets,…” Similarly, Freed et al. (18) state, “…there is virtually no history of nuclear construction under the economic and institutional circumstances that prevail throughout much of Europe and the United States,” and Cooper (19), who compared decarbonization scenarios, concluded, “Neither fossil fuels with CCS or nuclear power enters the least-cost, low-carbon portfolio.” Third, unlike Jacobson et al. (2), the IPCC, National Oceanic and Atmospheric Administration, National Renewable Energy Laboratory, and International Energy Agency have never performed or reviewed a cost analysis of grid stability under deep decarbonization. For example, MacDonald et al.’s (20) grid-stability analysis considered only electricity, which is only ∼20% of total energy, thus far from deep decarbonization. Furthermore, deep-decarbonization studies …