Jamais Cascio over at WorldChanging notes some interesting developments in biomass chemistry that may have the potential to help us transition to an oil-free economy.
So what's the biomass-based alternative to using petroleum for fertilizer?
Algae.
Engineer-Poet at the Ergosphere breaks it down. Algae can be used to produce hydrogen, and hydrogen can be used to "fix" nitrogen. With the hydrogen production operating a mere 1% efficiency, a hectare of hydrogen-generating algae could produce the nitrate to fertilize around 20 hectares of agricultural production. That same hectare could fertilize 200 hectares if H2 generation efficiency is brought up to the 10% thought possible.