Tidal Current Energy

154 P. Champagne
Table 9.1. Potential benefits and risks of using biomass for bioenergy.
Environmental protection Environmental threats
● reduced dependency on fossil fuels and
petroleum products
● lower greenhouse gas emissions
● reduced smog and toxic chemical emissions
Diversification of energy sources
● use of underutilized biomass resources as a
renewable feedstock
● use of waste materials reducing concerns
associated with disposal
Use of organic by-products and waste
● reduced quantities of liquid effluents
● reduced quantities of solid waste
● reduced contamination of air, water and soil
● reduced concerns associated with landfilling
and land application
Invigorating rural communities
● increased demand for forest, farm and aquatic
products, building on regional strengths
● localized production and creation of
employment in rural communities
An energy resource for developing economies
● more widely distributed access to energy
● export opportunities for biomass processing
and bioenergy-producing technologies
(Source: Ref. [5])
● depleted biomass carbon stocks, increased
atmospheric CO 2 and contribution to
climate change
● increased demand for fertilizers, herbicides and
pesticides leading to increased pollution and
greenhouse gas emissions
● use of genetically engineered crops and
microorganisms to produce bioproducts and
bioenergy possibly affecting ecosystems
● fast-growing, monoculture tree plantations
possibly more susceptible to disease
● fast-growing, monoculture tree plantations
possibly depleting local water supplies
● industrial cultivation of favored crop and tree
species possibly reducing biodiversity
● increased particulate carbon emissions from
wood burning
Land and water use conflicts
● use of land needed to supply food crops
● use of land and water for biomass production
that should be protected or reserved
for other uses
labor-intensive source of energy, a continued challenge which will need to be
overcome as strategies and technologies are developed to meet the biomass and
bioenergy requirements of society. Biomass has a relatively low energy density
compared with fossil fuels. Hence, fuel transport increases its cost and reduces
the net energy production. Locating energy conversion processes close to a
concentrated source of biomass lowers transportation distances, emissions and
costs. The production and processing of biomass can require significant energy
inputs, which must be minimized to maximize biomass conversion and energy
recovery [6]. However, compared with most other renewable energies, biomass
has the key advantage of inherent energy storage, which can be in solid, liquid
or gaseous form depending on the conversion process employed [6].
2. Biomass Resources
As the world population continues to grow exponentially, the demand for
energy is expected to increase at a similar rate, which, combined with the depletion
of non-renewable fossil fuels and a growing environmental awareness