Thanks to a new technique developed in the United States, the process of obtaining energy from biomass has improved significantly, and in the future it could be an important energy source in rural areas of poor countries. The combustion of biomass in the air allows to obtain methane and carbon monoxide, but the nitrogen contained in the air dissolves these gases, so the calorific power of the fuel is very low, an octave of the calorific power of natural gas.
The key to the new technique lies in differentiating combustion and heating processes. First, the biomass is burned with air in a tube and the heat generated passes into a metal gravel. Steam is then introduced into the pipe to transmit this heat from the gravel to the biomass, and once condensed, there is virtually nitrogen free gas. In this way, biomass can obtain up to three times more energy than previous fuels.