PhD Thesis - Energy Systems Research Unit - University of Strathclyde

the system are kept. The output of this program is the sizing and system
operation recommendation for the optimum supply system.
The search for an optimum solution is a reasonable pursuit if the system
contains only one or two supplies, and one or two auxiliary technologies.
However, when consideration is being given to a diverse range of possible
supplies and a wide variety of ways of integrating these to form an overall
supply system for electricity, heat and transportation, there will often be no
optimum answer. Searching for one best answer requires strict selection criteria
to be chosen, and rules out all other possibilities, which may, with a slight
technical, political, economic or demand change, be much more viable options.
It also does not allow the user to see emerging trends that may provide useful
information when designing a system that will be put in place gradually, or
when designing a system to allow for growth and expansion, especially when
the fine balances necessary in an integrated system are being considered. In
these cases, it is important to be able to explore the full range of possible
solutions in order to judge different scenarios on their relative merits.
3.3 The Use of Biomass and Waste
With the exception of F-Cast [2] that considered a limited use of biomass for
electricity production, and MERIT [8] which gives a small consideration to the
demand for heat, the systems described Section 3.2 look only at the production
and storage of electricity by PV, wind, batteries, pumped hydro plant, back-up
diesel generators and grid connection. They do not take into account the
valuable sustainable resource available in the form of biomass and waste and
their derived fuels, or the demands for heat and transport.
Other models exist which address some of these issues. For example, the
OREM (Optimum Renewable Energy Model) system described by Iniyan [12],
considers demands for cooking, transportation, pumping, lighting, heating,
cooling and electricity. These can be met by the use of wind, solar and PV
technologies, direct combustion of biomass and wastes, fermentation to produce
ethanol, and gasification to produce biogas. The aim of the model is to develop
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