This classic Joe Romm post lays out the nitty-gritty:
It would require some 12-14 of Princeton’s “stabilization wedges” — strategies and/or technologies that over a period of a few decades each ultimately reduce projected global carbon emissions by one billion metric tons per year (see technical paper here, less technical one here). These 12-14 wedges are my focus here.As my dad would say, as easy as falling off a log backwards.
I do believe only “one” solution exists in this sense — We must deploy every conceivable energy-efficient and low carbon technology that we have today as fast as we can. Princeton’s Pacala and Socolow proposed that this could be done over 50 years, but that is almost certainly too slow.
This is what the entire planet must achieve:
- 1 wedge of albedo change through white roofs and pavement (aka “soft geoengineering) — see “Geoengineering, adaptation and mitigation, Part 2: White roofs are the trillion-dollar solution“
- 1 wedge of vehicle efficiency — all cars 60 mpg, with no increase in miles traveled per vehicle.
- 1 of wind for power — one million large (2 MW peak) wind turbines
- 1 of wind for vehicles –another 2000 GW wind. Most cars must be plug-in hybrids or pure electric vehicles.
- 3 of concentrated solar thermal (aka solar baseload)– ~5000 GW peak.
- 3 of efficiency — one each for buildings, industry, and cogeneration/heat-recovery for a total of 15 to 20 million GW-hrs. A key strategy for reducing direct fossil fuel use for heating buildings (while also reducing air conditioning energy) is geothermal heat pumps.
- 1 of solar photovoltaics — 2000 GW peak
- 1/2 wedge of nuclear power– 350 GW
- 2 of forestry — End all tropical deforestation. Plant new trees over an area the size of the continental U.S.
- 1 wedge of WWII-style conservation, post-2030 [just a placeholder, will blog more on this later]
Here are additional wedges that require some major advances in applied research to be practical and scalable, but are considered plausible by serious analysts, especially post-2030:
- 1 of geothermal plus other ocean-based renewables (i.e. tidal, wave, and/or ocean thermal)
- 1 of coal with biomass cofiring plus carbon capture and storage — 400 GW of coal plus 200 GW biomass with CCS
- 1/2 wedge of next generation nuclear power — 350 GW
- 1/2 wedge of cellulosic biofuels for long-distance transport and what little aviation remains in 2050 — using 8% of the world’s cropland [or less land if yields significantly increase or algae-to-biofuels proves commercial at large scale].
- 1 of soils and/or biochar– Apply improved agricultural practices to all existing croplands and/or “charcoal created by pyrolysis of biomass.” Both are controversial today, but may prove scalable strategies.