Production of Methane Biogas as Fuel Through Anaerobic Digestion - Sustainable Biotechnology: Sources of Renewable Energy - page 120

barriers may be technological, economic/financial, environmental, or sociopoliti-
cal, and may also include subjective psychological components such as uncertainty,
perception, or fear. Despite their importance, the drivers and barriers for commer-
cial implementation of AD by companies or farms are rarely disclosed or detailed in
the literature because the information is typically related to business operations and
confidential. However, experience from on-site and cooperative studies of AD for
candidate factories or farms have shown that the satisfaction and resolution of multi-
ple drivers and barriers, respectively, is crucial in the decision making to implement
a specific AD project. Experience with pilot-scale AD studies conducted by anaer-
obic digester vendors has shown that both drivers and barriers are multi-faceted and
interdependent and vary in importance depending on a host of factors associated
with candidate factories and their biomass wastes. An AD project is unlikely to
proceed unless the full range of drivers and barriers are considered and the drivers
outweigh the barriers. The following section will discuss the drivers and barriers in
general, and how the advancement of AD technologies can contribute to tipping the
balance towards the drivers by mitigating many of the barriers, including those of
economic and political nature.
4.1 Drivers for Commercial Implementation of AD
The drivers that stimulate commercial interest to implement AD include a complex
set of economic, business, energy, environmental, and sociopolitical factors that are
interactive and may be weighted differently for each AD implementation opportu-
nity. The economic and business drivers relate to those that directly contribute to
the profitability of an AD project through the rate of return on the investment. These
drivers include (1) the revenues that can be realized by the production of biogas and
other byproducts (e.g., fertilizer), (2) the cost savings derived from reduced waste
disposal, (3) governmental credits (e.g., renewable energy credits, environmental
credits, and carbon credits) that are earned by implementation of a AD project, and
(4) potential business growth that results from overcoming the limitations posed
by storage and disposal of the wastes generated from core business operations.
Firstly, earned revenue from an AD project can be gained from sale of the bio-
gas as fuel or energy produced therefrom. Additional revenue can be generated by
receiving wastes from other factories or farms. A spillover benefit of such “service”
is enhanced AD efficiency and process stability resulting from co-digestion of two
or more types of biomass wastes. Secondly, AD is a proven technology to reduce
pollution, and thus its implementation can reduce or eliminate the fees paid to the
government for waste discharge or disposal. Depending on the nature and amounts
of wastes, this saving can be substantial. Thirdly, methane biogas produced fromAD
of biomass wastes can replace fossil fuels, therefore implementation of AD should
earn environmental and carbon credits as well as renewable energy credits that can
be sold for additional revenues. Finally, for many factories or farms that produce
large amounts of biomass wastes, the enterprise may be prevented from business