We, we humans, need to stop releasing fossil carbon into the atmosphere well before 2100 or we are doomed.
The main reason we are not heading headlong into that project, getting it done right away, is because of the fossil fuel industry combined with a deep seated self-hate on the part of Republicans, who would rather end civilization and make all of our children suffer than to do something an environmentalist might suggest.
The road to decarbonization is the same as the road to electrification plus the road to making all of our electricity with something other than coal, oil, methane, and the like. This could involve a certain amount of liquid fuel that is generated using wind and solar power, and magical bacteria or something, perhaps with a mix of plant material or other bio-sources.
There are easy ways to do part of this fast. For example, building wind farms is easy and produces piles of electricity. Same with solar. “But wait wait,” you say. “Those sources are intermittent, we can’t…” But I say to you, if this is your first thought, you are out of date (or are a Republican?). Solar and wind are indeed intermittent, but we can still use them as the backbone of our power system. This is a problem, but not one that can’t be figured out and has been, in fact, largely solved using a number of approaches. And, that is off the topic of this post.
We can also put solar panels on our roofs to a much greater degree than we do now. It has been estimated that a reasonable, not overdone but pretty thorough, deployment of PV panels on the roofs of America would cover about 40% of our in-building electrical needs as they stand now. This added to the eventual (though expensive, yet easy) deployment of heat pumps and total electrification of everything in those buildings probably averages out (the heat pumps reduce energy demand, the electrification increases demand for electricity as compared to gas or oil).
There are other types of low hanging fruit as well, such as increasing efficiency, telecommuting.
But what about the hard to do stuff, the major uses of energy that can’t be changes so easily?
There is a new review paper out in Science that discusses this. The paper is:
Net-zero emissions energy systems, boy Steven Davis, Nathan Lewis, Matthew Shaner, et al. Science 360(6396).
If you click on that link, you might be able to see the paper, as I think it is OpenAccess.
The paper identifies the following areas as tough nuts to crack:
- Long-distance transport
- Steel production
- Cement production
It identifies the following technologies as helpful:
- Hydrogen and ammonia fuels
- Synthetic hydrocarbons
- Direct solar fuels
The paper also identifies “highly reliable electricity” and energy storage as key areas of further development.
I do not see any major surprises in this paper, but that is because it is a review paper. I think it is a useful read to help organize one’s thinking on the transitions we will attempt, should the Republicans allow it, over the next decades.