Environmental Engineering Reference
In-Depth Information
producers. Food crop use is primarily a local area business so crops grown locally are processed
into biofuels and then used locally as well. This can be very beneficial for the environment. The
fact that biofuels will be more expensive (without distorting government subsidies) than petrofuels
is also favorable, because it will encourage the conservation of fuel and the development of more
fuel-efficient vehicles.
The logical place to start with crop production for biofuel is the major crops already grown
(such as canola/rapeseed) because all of the required knowledge and infrastructure needed to
produce these crops is already in place. In the longer term, a switch to non-food crops, especially
low input and perennial crops will eliminate the current controversy regarding growing our major
traditional food crops for fuel. Modern techniques such as use of GIS-based yield and suitability
mapping (Lovett et al. 2009) to study the bioenergy generation potentials of perennial biomass
crops and land use implications at regional scales could also aid in countering the issues in food
versus food issue.
18.5 Future ProsPects
The end of the petro oil era (not more than 30 years from now) will see a major shift in energy
production and use in the world. There will be a much greater reliance on biofuels for transportation.
Biodiesel is the most logical biofuel based on bioenergetic considerations. It has a positive energy
balance, and diesel engines are the most efficient of the internal combustion engines. Small diesel-
electric cars, which run primarily on stored electric energy from overnight recharging from the
electric grid with the diesel motor as a supplementary power source and portable battery recharging
source will likely predominate personal urban transportation (combined with biodiesel fuelled
buses).
Current vegetable oil crops, new vegetable oil crops, algal oil production and biomass conversion
to biodiesel via pyrolysis will all have a role to play in the future of biofuels. Nitrogen fixing crops—
current and new ones, and the conversion of existing crops to Nitrogen fixing crops will improve
the energy balance of crops. Production of low input marginal land adapted annual and perennial
crops for biomass to be converted via pyrolysis to biofuels, especially biodiesel, will predominate.
Perhaps perennial oilseed crops (perennial sunflowers or perennial flax for example) can provide a
portion of the vegetable oil needed for biodiesel in the future.
Life-cycle analysis, complete energy balance considerations, and full economic analyses of
potential bioenergy crops will be done to choose those oilseed crops most likely to provide the
environmental benefits we are hoping to achieve.
18.6 conclusIons
Brassica oilseeds are a major source of vegetable oil in the world. They are widely adapted
and readily bred to produce a wide range of edible and industrial oils. They display high seed
productivity, high oil productivity and high meal productivity. Canola oil is an excellent feedstock
for biodiesel production especially in temperate climates. New higher yielding, higher oil content
rapeseed cultivars will provide the oil required to satisfy both edible and nonedible (biodiesel and
industrial oil) markets. Oilseed Brassicas will be the predominant oilseeds grown in temperate
climates providing food, feed and fuel for the world. The economics of using Brassica oilseeds as
feedstock for energy (biodiesel) can be improved by increasing the oil content (<50%), increasing
the seed yield, and by further development of oilseed
Brassica
species including
B. juncea
and
B.
carinata
, and thereby increasing oil productivity per unit area. The development of abiotic and
biotic stress tolerant Brassica oilseed cultivars especially when combined with enhanced fertilizer
and water use efficiency traits will greatly improve the economics of Brassica oilseed production
for all uses including energy.
