Energy is not an end in itself but a means to provide a number of services.
Businesses and households view energy as an input, an expense of doing
business or maintaining a home. In general people are less concerned with
how many kilowatthours they purchase than with the services such as heat,
light and appliances which electricity can provide. This relationship provides
the basis of Demand Side Management (DSM).
DSM is defined as “The planning and implementation of strategies designed
to encourage consumers to improve energy efficiency, reduce energy costs,
change the time of usage or promote the use of a different energy source”, It
is a partnership between the utility and customer with benefits to both.
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DSM tries to reduce the peak load and change the shape of the load profile
through the techniques of energy conservation, peak clipping and load
shifting. Correctly implemented, DSM can reduce energy consumption with
the associated financial and environmental benefits.
Some strategies such as energy efficiency measures, education in energy use
and technical advances in control can help with DSM. Of these strategies,
education in energy use is the cheapest to implement, energy efficiency is
often the easiest to carry out and load shifting is the most difficult to
accomplish with technical, financial and social factors to overcome.
Energy efficiency is defined largely as cost-effective measures to reduce
energy consumption through existing and improved technologies, as well as
through sound energy use practices. The idea behind energy efficiency is
quite simple - if people consume less energy, there will be less emission of
greenhouse gases as the result of the burning of fossil fuels in power stations.
Energy efficiency technologies and practices can therefore play a significant
role in reducing the threat of global climate change.
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Load shifting is the process of manipulating loads to remove the problematic
peaks that occur in demand profiles that aggregate across the community to
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give large temporal peaks. It attempts to move the demand that gives rise to
these peaks to times of lower demand, or valleys, between peaks present in
the demand profile.
By attempting to maintain the demand at a more or less constant level, the
stress placed upon equipment and the wastage imposed upon the generating
facilities by the need to maintain spinning reserve will be much reduced,
leading to lower operating costs that will eventually be passed onto the
consumer.
Managing the demand in the network is a good way of saving expenditure on
infrastructure, as the cost of this type of scheme is considerably less than
reinforcing or upgrading existing infrastructure.3
The technique of load shifting can be utilised once other more cost effective
measures have been addressed and implemented, such as the range of
energy efficiency measures.
There is only a relatively small amount of historical data concerning load
shifting. Most of the information that is available concerns the effects of
bringing metering with two rates, a high and low rate, into the domestic
electricity market.
The literature review of the area showed that any load shifting that occurred
was generally quite crude. The loads were shifted from their normal period of
operation during the high rate period to a time to the lower rate period by the
use of time switches in order to take advantage of lower overnight tariffs.
Energy expenditure is rising inexorably with an increased amount of
disposable income per household allowing more labour saving and leisure
appliances to be purchased and operated. Managing this option would seem
to be the sensible option, as it will hopefully allow better operation of
generation plant and propagate a degree of energy awareness through the
population.
With the steady increase in price of all types of fuel over the past few years,
there has been an increased focus on the entire area of energy management.
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DSM has been embraced as a way forward as it is seen as a way to increase
profitability by the saving of needless expense