Study Concludes Afforestation of Degraded Areas Could Provide Sufficient Biomass for Global Energy Supply; BTL for Transportation Fuels
A pair of German researchers has concluded that the global energy demand projected by the International Energy Agency in the Reference Scenario for the year 2030 could theoretically be provided sustainably and economically primarily from lignocellulosic biomass grown on areas which have been degraded by human activities in historical times.
According to Prof. Jürgen O. Metzger from Carl von Ossietzky Universität Oldenburg, and Prof. Aloys Hüttermann from the Universität Göttingen, a global energy supply based on biomass grown to generate electricity and produce fuel is both a sustainable and economical scenario, contrary to some other current research. Their findings are published online this week in the journal Naturwissenschaften.
The solution, according to Metzger and Hüttermann, is to plant fast-growing trees on degraded areas, and harvest the biomass for energy usage. This afforestation would not compete with the need for arable land for food production. The authors argue that the investment required for afforestation and transformation of the biomass to electrical energy, heat, fuels and chemical feedstock is actually sustainable and not more, probably even less, than what would need to be invested in infrastructure for non-sustainable fossil energy.
For their global overall estimations for transportation fuels, the two used the conversion of the lignocellulosic biomass to biooil (“bioslurry”) via pyrolysis and its subsequent gasification to a syngas followed by Fischer–Tropsch synthesis (biomass-to-liquids, BTL).
They noted that while the production of methanol from the syngas and the subsequent use of methanol as fuel and as liquid energy storage offered higher energy efficiency, there would be problems that would arise with methanol as fuel and that the presently available Internal Combustion Engines would have to be modified to methanol-specific engines.
Methods of afforestation of degraded areas, cultivation, and energetic usage of lignocellulosic biomass are available but have to be further improved. Afforestation can be started immediately, has an impact in some few years, and may be realized in some decades.
...Clearly, it cannot be realized in 2030 because it has not been started. However, if afforestation to realize the Biomass Scenario would have been started say in 1992 after the Rio conference, we could observe already today an impact which would steadily increase and lignocellulosic biomass would contribute an important percentage to the primary energy supply in 2030.—Metzger and Hüttermann
The continuous use of biomass as an energy source is also carbon neutral which means that the energetic usage produces not more CO2 as used for the growth of the respective biomass, thus slowing down and stopping the build-up of CO2 and even slowly reducing the CO2 content in the atmosphere. Their scenario would also have a number of additional advantages, including a convenient way of storing energy, regenerating the global water and especially drinking water resources and controlling soil degradation.
Other renewable energies, including solar, tidal and wind power will contribute to the energy mix, making the biomass scenario even more realistic. The authors concede that new technologies will be required to convert the chemical energy stored in biomass to electrical energy more efficiently.
Metzger JO and Hüttermann A (2008) Sustainable global energy supply based on lignocellulosic biomass from afforestation of degraded areas. Naturwissenschaften doi: 10.1007/s00114-008-0479-4