The discomforting news: A lead essay in the Economist magazine reports that assumptions under the 2015 Paris climate accord include not just reducing CO2 emissions. The proposed temperature target of trying to limit temperature increase to less than 2ᵒ C includes removing about 890 billion tons of atmospheric CO2 by 2100. In scientific terms, that's a lot. That point is not well-reported.
The Economist sums it up: “Stopping the flow of carbon dioxide into the atmosphere is not enough. It has to be sucked out, too. . . . Unless policymakers take negative emissions seriously, the promise of Paris will ring ever more hollow.”
The good news: In summarizing promising technology advances for 2017, Scientific American reports on progress in technology that removes CO2 from air and converts it to fuel. Scientists have been working for decades on an artificial ‘leaf’ that uses sunlight, water and CO2 in the air to make alcohol fuels. In a significant advance, scientists at Harvard reported an artificial leaf that was much more efficient in converting CO2 and water to alcohol fuels than plant leaves are at converting CO2 and water to sugars (biological fuels).
In using sunlight for energy production, a plant uses about 1% of the energy in sunlight to make glucose (a carbohydrate or sugar). By contrast, the artificial leaf operated at 10% sunlight efficiency in converting CO2 in air to fuel. That system pulled 6.3 oz of CO2 from air per kilowatt-hour of electricity generated.
The scientists are in talks with industry to prototype large scale facilities to generate tons of fuels.
The technology includes (i) a non-toxic, biocompatible catalyst that splits water into hydrogen and oxygen using sunlight, and (ii) genetically engineered bacteria that use CO2 and the hydrogen to make fuel. The lead scientist envisions also using genetically engineered bacteria in soil to take CO2 and nitrogen from air to make fertilizers for plants.
So long as climate change deniers don't decide to intervene to stop or impede research,[1] there are developing technologies that can potentially have an impact on CO2 emissions. Presumably this technology an also be used to achieve at least some of the negative CO2 emissions that are believed necessary to stabilize the climate.
The unknown: Whether this and other developing technologies can be scaled up and still be economically competitive in time to make any difference is unknowable. It is possible that humans have already set in motion biological-geological processes that could lead to human extinction, e.g., anoxic oceans leading to a toxic atmosphere. The timescales and odds for very bad outcomes are impossible to know with any degree of certainty.
Footnote:
1. In the case of gun control research, gun advocates and political conservatives have successfully blocked funding for research on the public health impacts of gun ownership since 1996. Conservatives in congress today want to cut funding for Earth and climate science research to block research and new information that reveals the scope and nature of climate change. In this case, conservatives and/or economic interest who feel threatened by this new source of energy cold stop research and or development of this new technology. Much of the effort to stop science and new knowledge is well-funded and operating in as much secrecy as possible.
B&B orig: 12/31/17
No comments:
Post a Comment