The State of Hawaii exempts proceeds from the retail sale of fuels containing at least 10 percent biomass-derived alcohol from the general excise tax. Growing biomass crops produce oxygen and use carbon dioxide. Utilization of waste materials reduces landfill disposal volume and potential pollution problems. Carbon dioxide, which is released when biomass fuel is burned, is recaptured by growing plants. Disadvantages Agricultural wastes, such as bagasse, will not be available if the basic crop is no longer grown.
Additional work is needed in areas such as harvesting methods.
Land used for energy crops may be in demand for other purposes, such as farming, conservation, watersheds, housing, resort or industrial use. Some biomass conversion projects from animal wastes are relatively small and therefore limited to on-site power production only. Some liquid fuels, such as ethanol and methanol, contain less energy per gallon than gasoline. Research is needed to reduce the costs of production of biomass-based fuels. The Basic Process Plants use sunlight for growth in a process called photosynthesis.