Environmental Engineering Reference
In-Depth Information
used to produce the energy made from the methane.
Localities and large farms are increasingly turning to
using the methane from waste rather than letting it go
into the atmosphere.
Bacteria and algae have a potential that is only begin-
ning to be explored. There are biological systems that
directly convert sunlight and nutrients into useful energy
products. One example is the conversion of water into
hydrogen and oxygen driven by sunlight and a modi
ed
photosynthesis cycle. The problem with this and many
similar cycles is their inef
ciency, but the hope was that
bioengineering would improve them. Regrettably, that
hope has not been realized. The National Academy of
Sciences concluded as follows in its report Sustainable
Development of Algal Biofuels [
]:
Based on a review of literature published until the authoring of
this report, the committee concluded that the scale-up of algal
biofuel production suf
percent of US
demand for transportation fuels would place unsustainable
demands on energy, water, and nutrients with current tech-
nologies and knowledge. However, the potential to shift this
dynamic through improvements in biological and engineering
variables exists.
cient to meet at least
Several companies were started to commercialize this
approach. None has succeeded.
.
Summary
In discussing the Phase-
programs I have focused on
corn and sugarcane. There are other sources as well and
the conclusions about them are not signi
cantly different.
