Environmental Engineering Reference
In-Depth Information
Figure 1.6
Sprawling solar energy complex in San Luis Valley, CO.
1.1.2.3 Solar Biomass Energy
Indirectharvestingofsolarenergyviabiomass(ineffectiveastheconversion
might be as pointed out already) is a growing renewable energy strategy.
The best-known example is the use of corn-based alcohol as fuel. In the
United States, up to 10% ethanol is typically blended into gasoline, and in
2010, 40% of the US corn production was diverted from feed/food uses
technologies can be scaled up and implemented quickly, an approach that
converts agricultural food-producing land into fuel-producing acreage has
obvious drawbacks. In 2007, 47% of vegetable oil in the EU was used for
biodiesel production but still contributed only to 0.36% of the global energy
supply (UNESCO, 2009)! Biomass such as marine algae, cellulosic waste, or
rapidly growing nonfood land species (switchgrass) can also be converted
into fuel. Using these in place of corn biomass will make far better economic
sense in the future. Available crop varieties presently yield less than 1 W/m
2
of land used.
1.2 MATERIALS DEMAND IN THE FUTURE
Thomas Malthus (Cambridge University) in 1798 predicted a catastrophic
fate for the human race due to a growing population outrunning its
subsistence. More recently, Paul Ehrlich (1974) predicted materials
