Bio-fuel's impact on water

The increasing use of bio-fuels has prompted vivid discussions including ethical and moral concerns regarding the rocketing prices of crops. Currently, most of the energy consumption comes from oil (34%), coal (25%) and gas (20%), but most of the projections point that, in a couple of decades, solar and biomass energy will account for the majority of the energy supply.

Biomass energy is nothing new. To date, the global energy consumption of biomass averages 10,7%, but in some countries biomass is the main source of energy supply (in Ethiopia, 90% of the energy supply).

Nowadays, most of the bio-energy supply comes from the first generation of biomass, consisting of corn, soybeans, sugarcane, palm oil and the kind. This poses advantages and disadvantages.

Among the former, the security of the supply, high energy density –which makes it good for transport–, support to agriculture and job generation in this sector and the supposed-but-not-fully-proved low net green house emissions.

On the other hand, the high generation of carbon emissions could be found among the disadvantages, together with increasing food prices, draining of peat land and increasing use of water in highly water stressed areas.

“There are too many unknown answers to questions brought up by the use of bio-fuels”, points Stefan Uhlenbrook, professor of Hydrology at UNESCO-IHE. He explains that some answers may lie on Jathopa, a plant which grows in Indonesia. It doesn’t compete with crops as it is toxic, it tolerates poor soil conditions, it is drought resistant and it can be produced locally.

Nevertheless, grown in extensive plantations, it could affect evaporation patterns, which would affect rain patterns not only locally but regionally.

The answer could lie on the second generation of biomass, consisting of cellulose materials or plant residues. Nevertheless researchers need to better understand the conversion methods and processes, the effective ways of fermenting, how to elaborate complex fuels. In addition, the environmental, socio-economic and hydrological impacts of extensive biomass production need to be assessed and analysed.

Biofuels and biomass present many opportunities, but these opportunities don’t come free from negative effects. The sooner research can identify complex and interdisciplinary interactions of bio-energy, the sooner the negative effects can be mitigated in order to ensure that biomass will provide 1/3 of the future energy demand in an effective and sustainable way.