Biofuels are not the Answer
Posted by butalidnl on 20 August 2011
Biofuels have been hailed as our way out of the dependence on fossil fuels. In the US, massive amounts of government funds have gone into making ethanol from corn. In the Philippines, the 2006 Biofuels Act targets the mixing of 5% ethanol in gasoline and 1% biodiesel in petrodiesel.
Biofuels as the solution to the energy problem is a myth, especially if you look deeper into its real prospects. Experts have computed that, in order to supply enough fuel for US’ transportation needs, they would have to grow corn in 3x the current cropland of the US. In other words, it is impossible for corn to do the job.
But why is that the case? Well, plants are actually (contrary to the myth) very inefficient transformers of solar energy. Plants transform only about 1% of the energy from sunlight into plant material. And of this plant material, perhaps only 20% (or 0.2% of the total) gets into the corn cob, which is what is processed towards ethanol. Then, the processing uses up energy. The end result is that only about 0.1% (one-thousandth) of the sun’s energy is transformed into ethanol.
Contrast this with silicon solar panels, which transform 16% of sunlight into energy. This is 160 times the energy obtained from corn! Some solar panels can even achieve 30% efficiency; but these are made with expensive Gallium Arsenide, and are thus only used for things like space satellites.
The main ‘problem’ that silicon solar panels face is that they still cost too much to make, making it cheaper to rely on traditional sources of energy. But the cost of making solar panels is rapidly going down; even to the point where it has reached ‘grid parity’ (i.e. solar costs the same as ordinary electricity) for some places or applications. Reaching grid parity is important because this means that subsidies will no longer be necessary for these applications.
Cellulose and Algae
There are efforts aimed at using cellulose or algae as the source of biofuels. Using cellulose would mean that the full 1% of sunlight that the plant transforms will be used. Algae transforms up to 3% of sunlight, but they require expensive glass containers (which need to be regularly cleaned) so that the net yield of algae would be something like 1.5%. Another problem with algae is that it grows slowly when it is producing hydrocarbons.
Algae is only marginally better than cellulose. And there is still a long road ahead, in terms of bringing either cellulose or algae to even get to 1-1.5% efficiency. It is a terrible waste of money to spend so much on biofuels of any kind. At the same time, solar is already 16 times more productive than algae and cellulose will ever be. And with further research, it should be possible to raise solar’s efficiency even more.
Use Other Technologies
The logical conclusion to all this would be that governments should stop all subsidies for biofuels immediately, and to rechannel the funds to more promising technologies. I suggest that these be solar, geothermal and wind. With a relatively small amount of research on solar and wind, their efficiency stands to improve a lot. Geothermal needs relatively big investments, but pays off well. Geothermal costs much less than traditional sources of energy to generate. At the same time, the use of electric cars should be stimulated, so that gasoline and diesel will be replaced by electricity.
The Philippines should rescind the 2006 Biofuels Act. It is already a failure. Both ethanol and biodiesel are suffering from “volatile prices and insufficient supply”. This is a natural result of the inefficiency of their production; and this basic inefficiency means that prices and supply will never be satisfactory, even with subsidies. Instead of biofuels, the Philippines should stress more on geothermal and solar, which are a lot more cost effective, and for which future price developments are growing more favorable.