A worker at green energy producer 4Energy Invest looks at biomass at Renogen plant in Amel April 2, 2010. Belgian bio-coal maker 4Energy Invest expects earnings to rise 10 percent in the second half of 2010, and sees sales up tenfold within four years on a surge in demand for the CO2-neutral fuel. To match interview 4ENERGY/ REUTERS/Thierry Roge (BELGIUM - Tags: ENVIRONMENT SOCIETY)