Why treat all forms of carbon emissions alike?
By Eric de Place
This is the seventh in a short series of posts that explain some important but often overlooked policy issues in the Western Climate Initiative -- the West's regional cap-and-trade system.
Earlier in this series, I've worried that WCI is waiting too long to include some major sources of climate pollution in their program. But worse, they are also proposing to completely ignore some sources of emissions. Early on, the latest draft contains this terse statement:
Carbon dioxide emissions from the combustion of biomass or biofuel are not included in the cap-and-trade program.
This is alarming. Ignoring biofuels in a cap and trade program is like investing in insulation for your house but forgetting to shut the windows.
Somewhat strangely there's no explanation for this statement. At minimum, however, it demands elaboration as the terms "biomass" and "biofuel" can refer to a vast and diverse array of products, some of which are climate killers and others of which may yet be climate saviors. "Biomass” can refer to everything from corn for ethanol to algae to Indonesian palm oil to Oregon canola. It can refer to argricultural waste from wheat harvesting to the woody slash left by small-scale logging; or it can even mean your table scraps. The point is: these are very different things, with very different features and climate consequences.
"Biofuels" are similarly hard to pin down. On one reading of WCI's statment you might wonder if gasoline blended with corn ethanol and diesel blended with soybean biodiesel will be entirely off the hook? (B-20 biodiesel, for instance, is considered a "biofuel" but it's still 80 percent petroleum-based.) Or does the draft just that the biological components of those fuels will be ignored? Presumably, it's the later, but it would be nice for WCI to say that clearly.
Not that greater clarity alone would solve the problem here. There is evidence that at least some conventional biofuels are harmful to the climate, perhaps extremely harmful. We need to be careful about how we treat them.
It's sometimes asserted that biomass can be ignored because it's part of the "carbon cycle" and can be replaced by future biological growth. That may be true in a few specific instances, but it's an extremely simplistic approach to a very complex subject. It ignores the fact that some forms of biomass extraction -- say, clearing an old growth forest -- release so much carbon that it would take decades, even centuries, to replace the carbon on-site. It also ignores the indirect but very real effects that land use choices have on global fuel demand, as well as on demand for additional land conversion. It can be very difficult to accurately account for these factors, but that doesn't make them unimportant.
The solution is fairly simple. When combusted for energy, "biomass" shouldn’t be treated differently from any other source of carbon emitted. It's greenhouse gas emissions should be tallied, or at least estimated, and polluters should be required to obtain carbon allowances in proportion to their emissions.
To be clear, my simple solution would not account for the complex supply-chain issues that I've mentioned above -- dealing with those would probably require a life-cycle analysis. But still, counting the direct carbon emissions would at least tilt the playing field back to something approaching level. Ultimately, perhaps, we'll develop measurement protocols that will allow us to address the "upstream" carbon of our energy choices -- fossil fuels and biomass alike.
In the meantime, however, to simply ignore biomass and biofuels is an invitation to “fuel-switching”: to run electricity plants off wood waste rather than natural gas; to heat homes with wood rather than gas; and so on. Now in some cases, these may be good ideas. But in other cases it's probably not. For example, fuel switching your car from a PHEV, using natural gas-generated electricity, to corn ethanol probably isn't a great idea.
Unfortunately, under the current proposal WCI will only count -- and price -- the emissions from fossil fuels and not the emissions from biomass, even though the carbon each releases has exactly the same effect on the atmosphere. Ignoring the carbon from biomass will build in weird incentives that may be counterproductive: some carbon emissions will carry a price, but other emissions will be free and will therefore not reflect their damage to the climate. Naturally, of course, we'll gravitate to the free sources of carbon, without regard for their harm.
Well, the same is true for wind and solar, whose lifecycle emissions are - according to the latest EU figures - slightly higher than biomass combusted in dedicated plants.
Lifecycle emissions per GWh generated (CO2 equivalent in tonnes)
Solar PV: 100 tp 150 ton CO2eq / GWh
Wind: 30 to 50 ton CO2eq / GWh
Biomass combustion: 20 to 30 ton CO2 / GWh
Large hydro: 15 to 30 ton CO2eq / GWh
In short, let's treat all energy sources alike. Let's make no exceptions.
Jacob - could you please provide the source of your numbers? I would be quite interested to see how these figures were generated to become better informed.