m28.    How is biomass used for energy?

Energy plantations produce cottonwoods, poplars, sycamores, shrubs, water hyacinths, and other fast growing plants. Oil palms and varieties of Euphorbia plants store energy in hydrocarbons, which can be refined as gasoline. More than 70% of people in less developed countries use wood for cooking and heating. About 23% of the electricity used in Maine and 4% of that used in New England comes from wood fueled plants. Wood burning released CO₂ and is responsible for 820 cancer deaths a year in the US. Crop residues and manure can be burned or converted to biofuels; 58% of the energy produced on Kauai and 33% of the energy produced on Hawaii comes from burning sugar cane residue. China has more than 6 million biogas digesters.  The solid residue is used for fertilizer. Gasohol is 10-23% pure ethanol mixed with gasoline; 35% of the gasoline sales in Illinois, Iowa, Kentucky and Nebraska are from gasohol.

e10.    Why do organisms become extinct?

e11.    What types of old-growth forests are there?

e12.    Where are tropical forests?

e13.    What is biomass?  

e16.    What do computer models of greenhouse changes show?

g18.    What is energy?