PhD Thesis - Energy Systems Research Unit - University of Strathclyde

a system for the sustainable production of energy for India for the year 2020 by
minimising the cost/efficiency ratio within the bounds of social acceptance,
reliability, demand, and potential supply. This model, however, looks at the
energy requirements for the year as a whole, and does not take into account the
variable nature of the intermittent supply technologies. It can, therefore, not be
used to aid decisions about the suitable type and sizing of storage devices or
auxiliary plant that may be required.
Another system, RETScreen [13], has been developed for the Canadian
government. This is an Excel spreadsheet based model, which can be used
worldwide to evaluate the energy production, life-cycle costs, and greenhouse
gas emissions reductions for various single renewable energy technologies.
These technologies include wind, PV, biomass heating, solar water and air
heating, small-scale hydro, passive solar heating, and the use of ground source
heat pumps. These models provide a good in-depth technical and economic
assessment of these technologies used on their own, but do not consider the
integration of these systems and, again, deal with annual energy requirements
only.
Ramakumar et al. [14,15] describe the use of the IRES-KB system to allow the
technical analysis of potential renewable energy supply systems for remote
areas. Demands for electricity, heat and mechanical power are considered, and
these may be met by biogas from digested biomass, solar-thermal energy,
hydropower, wind turbines, and PV panels. The year is split up into seasons,
each of which is characterised by a set of daily demands and available resources.
This information is input as energy needs per day for refrigeration, cooking,
lighting etc, and as available wood and crop residues, volume of falling water,
and a choice of pre-programmed cloud cover and wind regimes. These demands
and supplies are split up throughout the day in hourly intervals, and some
variability is added to the intermittent supplies through the cloud cover and wind
regimes chosen, in order to analyse the required storage and reserve plant sizes.
This system provides a good seasonal evaluation of the energy supplies and
demands of an area, however, it lacks the more in-depth temporal analysis that
would be necessary when considering more complex systems.
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