In Reinventing Fire, 2050 natural gas consumption is reduced by 36% relative to business-as-usual. Unlike coal and oil, natural gas is not eliminated by 2050 because it’s flexible and relatively inexpensive. (It’s also domestically sourced and burns much cleaner than coal or oil.) Natural gas can be used across a wide spectrum of centralized and distributed applications including combined heat and power— a key component of the industrial sector transition away from oil and coal. It can power the flexible combustion turbines and combined-cycle power plants that help balance variable renewable generators (wind and photovoltaics). It also provides a convenient and efficient source of heating to residential and commercial buildings. Roughly 5% of the natural gas consumption shown in 2050 comes from waste streams (landfill gas, anerobic digesters, etc.).
Using gas much more efficiently and successfully exploiting new sources of natural gas (notably “fracking” gas-rich shales) could keep natural gas prices affordable and relatively stable—supporting the transition described in Reinventing Fire. However, should the significant uncertainties about shale gas not be resolved favorably, which will take at least a decade to know (see Reinventing Fire, p. 233), our vision is not dependent on it.
The nominal 36% lower gas use in 2050 than in 2010, despite a 2.58-fold bigger economy, is probably conservative (tending to overstate gas consumption). Our analysis assumes combined heat and power only in industry, not in buildings, which also have major potential. We also assumed no solar process heat even in 2050, though some of it is profitable today, it’s likely to get cheaper as production scales up (like other renewables) while gas prices trend upward. There is also ample scope for further substitution of electricity and solar thermal technologies (active or passive) in commercial and residential buildings, and in the electricity sector, storage (such as currently viable compressed-air storage), or fuel cells using electrolytic hydrogen, could substitute for natural gas.