CO2 Reductions: The Technology Gap
MIT (Lester and Finan, 2009) analysis shows the amount of additional carbon-free energy from various sources (green) needed by 2050, compared to amount from these sources today (blue), in order to reduce U.S. power sector CO2 emissions 80% from today’s levels. This assumes energy efficiency is increased 3% annually in the U.S., a rate 50% faster than recent trends.
Carbon dioxide emitted mostly by the burning of fossil fuels has locked our planet into a global temperature rise of more than 2° C this century, compared to temperatures before the Industrial Revolution. A number of factors contribute to global warming. By driving cars, using electricity from coal-fired power plants, and heating our homes with fossil fuels, we release CO2 and other heat-trapping gases into the atmosphere. Deforestation also releases CO2, as fewer trees means less CO2 is converted to oxygen.
Greenhouse gases (GHGs), such as carbon dioxide, accumulate in the atmosphere, trapping heat that normally would exit into space. While many GHGs occur naturally and are needed to create the greenhouse effect that allows the Earth to support life as we know it, human use of fossil fuels is the main contributor to excess greenhouse gases.
During the 150 years of the industrial age, the atmospheric concentration of CO2 has increased by 31%. Over the same period, the level of atmospheric methane, another potent climate forcer, has more than doubled.
At the same time, sulfur dioxide and some other pollutants from power plants and factories have actually shielded the planet from as much as an additional degree of warming that would have otherwise occurred. In effect, particulate pollution has “masked” the earth by blocking and reflecting sunlight back into space, resulting in lower global temperatures than would otherwise be the case.
This creates an ironic challenge for environmental protection and health advocates: efforts to reduce this air pollution will save hundreds of thousands of lives worldwide, yet these efforts can also hasten global warming. As these emissions decline, the ‘masking effect’ on the climate is removed, leading to an even more rapid pace of warming in the next few decades.
Simply put, we are entering terra incognita in climate science. We have little historical understanding, and no direct experience, as to how human civilization and the Earth’s ecosystems will respond to climate warming of the amount and speed we appear to be facing.
The task ahead is enormous. Even within the relatively optimistic illustration depicted in the chart above, it is almost impossible to grasp the scale of carbon-free generating capacity needed to reduce U.S. carbon electricity emissions 80% by 2050 (blue plus green) versus the amount of such capacity in place in 2010 (blue only).
To make sure policymakers move quickly on the best solutions possible, CATF is working to create a portfolio of options that can get the world to zero carbon emissions in a timely fashion. To address this crisis seriously and efficiently, we must spark substantial additional technological and commercial innovation. The options must include:
Finally, we also focus on pollutants with short atmospheric lifetimes —methane, black carbon (BC), and ozone—where climate will respond faster to reductions.