This module covers “demand-side management” or DSM, as applied to energy
efficiency measures that modify or reduce end-users’ energy demand. This has
traditionally been applied to electricity loads but is also used for changes that
can be made to demands for all types of energy. The benefits for the energy user
are reduced energy costs for a given output (production level or other measure
of activity). For the energy provider, the benefit is a better use of its supply
capacity.
From a utility point of view it would seem that a sensible business approach
would be the promotion of consumption thereby increasing sales. This would be
true if there were an excess of capacity and revenues were the only important
factor in an energy supply system. However, increased revenues does not translate
necessarily in higher profits and in some situations a least-cost planning
approach would/could prove the implementation of DSM measures to be more
profitable than investing in new generating capacity. Utilities might therefore be
better advised to promote DSM and energy saving. From an environmental
perspective, a decrease in energy demand due to improved efficiency reduces
the environmental impact of energy consumption associated with a particular
level of production or other activity. In this respect, promoting DSM can thus
enhance the public image of a utility company.
Most of the literature and case studies relating to DSM are linked to electrical
demand as a result of programmes set up by utilities and governments and thus
this module concentrates on electrical DSM programmes. However, in Africa,
where a modest percentage of the population have access to utility generated
electricity, it is also necessary to consider DSM in relation to other energy
resources—on perhaps a local level. Here an important resource is biomass in
the form of wood for space heating and cooking. In this scenario, the supply and
demand is often met by the same person and hence self-regulating—the one bearing
the load of wood searching and collection will certainly manage the demand
and use the supply of wood efficiently as far as their energy use methods/
technologies allow e.g. stove types.
There are technologies that assist with the efficiency of wood fuel cooking, such
as improved cook stoves. However, in the United Republic of Tanzania, as in many
other sub-Saharan countries, the majority of rural people are poor and since they
can collect firewood for free, they cannot be easily motivated to purchase
improved stoves. Improved stoves for rural applications must therefore utilize
cheap and innovative clay stove technologies to keep costs as low as possible