David Cohen at ASPO-USA (also The Energy Bulletin) makes obvious something that I hadn’t realized before: Energy Secretary Chu’s (and by extension President Obama’s) energy policy, in relying on 4th generation biofuels, puts its faith in a radical form of geoengineering.

Cohen thinks the odds of pulling off that gamble at all, much less without unforeseen and unintended consequences, are slim.

Chu wants nothing less than to alter the Earth’s primary productivity – the proportion of the sun’s energy available to and assimilated by plants – to achieve greater efficiency in the conversion of sunlight to chemical energy than Nature has after 3.5 billion years of evolution.

After the costs of respiration, plant net primary production is about 0.05% of the solar constant. Note that this is the “average” efficiency, and in land plants this value can reach ~2-3% and in aquatic systems this value can reach ~1%. This relatively low efficiency of conversion of solar energy into energy in carbon compounds sets the overall amount of energy available to heterotrophs at all other trophic levels. Chu’s objective is to design microbes and plants which have been genetically altered to speed up or enhance photosynthesis. Chu describes his strategy for developing 4th generation biofuels as a “portfolio” approach.  This is from a news report on his confirmation hearings:

Such a multi-pronged approach looks to optimize all phases of biofuels production with no preconceived idea of which area is likely to offer the biggest payoff. And that, Chu said, “is why I’m so optimistic some real progress can be made.”

Cohen rechristens it as “scattershot” approach – randomly fire a lot of bullets in some general direction and hope you hit something – and points out it really means we don’t have a clue which ideas might work:

“No preconceived idea” means “I have no idea.”

Even if the research efforts should bear fruit, putting 4th generation biofuels to work will require the creation of artificial ecosystems, i.e. systems which have been human-designed and -engineered for specific purposes. Cohen cautions the mere fact that evolution has placed upper bounds on the efficiency of primary productivity in plants suggests that there are very deep reasons why this is so and that tampering with plant productivity may be a grave mistake or impossible.

Large-scale production of 4th generation biofuels is a form of geoengineering. We will plant energy crops on a land area of unknown size—this depends on the efficiency of the solar energy collection. (If no or only minor efficiency gains are achieved, there won’t be enough land.) Then we will harvest those crops and transport them to biorefineries, where biomass will be converted to fuels as shown in Figure 1. It is unknown how much energy the entire pathway itself would require, so we don’t know what the net energy will be. * * *

The lack of humility before Nature displayed here is nothing short of astonishing.

Cohen objects we shouldn’t be betting the farm on the unknown outcome of all these science experiments, and asks:

Why is geoengineering preferable to implementing sensible policies that promote liquid fuels frugality? Are these people crazy?

Here’s a synopsis of Cohen’s apologia for what would objectively seem to be insanity:

Human beings are very resistant to change. Societal behavioral changes are always gradual unless shocks occur that put large behavioral changes in motion. In the absence of such shocks, solutions to problems requiring rapid and deep behavioral change are politically impossible. Even politicians promising “change” quickly get with the program, which essentially amounts to doing nothing (doing nothing is a choice: it allows events take their natural course.) The promise offered by the magical technological solution to any problem is almost irresistible. If a problem is serious, as with energy, the more time a technological solution requires, the more popular it will be with politicians for whom gradual solutions are always good and shocks are always bad.

But his question remains:

Are these people crazy?