The hot weather electricity outages we are experiencing are not unique to Israel. They have
occurred in most parts of the world including the US and Canada and we can learn from measures they have taken. The ?rolling?
blackouts, we are experiencing in limited areas, are essential precautionary measures to prevent the electricity grid from
failing. As a matter of course, immediate demands are heard for increasing the number of power stations, while
short term and more economical yet effective means for restoring the balance between supply and demand by shifting a proportion
of the load to off-peak hours are unfortunately neglected. This process is known as ?load shedding?, a well-known system for
voluntarily or automatically cutting off the electric supply to selected low priority appliances when the demand exceeds available
supply During news reports, we hear appeals to avoid using elevators in order to conserve electricity.
But people in high buildings are not going to take this advice. Nevertheless savings can be achieved in buildings with more
than one elevator, by leaving only one in operation during peak hours. Some countries including Brazil, California,
New Zealand, and Norway have launched aggressive programs to quickly conserve electricity by a combination of measures to
change consumer behavior. Their programs have shown that it is possible to quickly reduce electricity demand by up to
20%, without major disruption or hardships. In some cases this has been achieved in a few months. To encourage
consumers to change habits, some utilities have introduced a cost incentive, in the form of "time-of-day" rates that
charge people less for using power during off-peak periods. An example of city-wide voluntary load shedding was
introduced by the city of Columbia, Missouri to reduce peak demand at the customer level. Participation in the Load Shedding
program is open to commercial and industrial customers who have demand levels of 250 kilowatts (kW) or higher during any month
between June and September. As an incentive for participation, a credit of $48 per year is paid for each kilowatt of load
shed. A major area in which savings can be effected is replacement of incandescent light bulbs with much more
efficient compact fluorescents. This was effectively carried out in Brazil, California, and New Zealand. California
consumers installed nearly eight million CFLs during the crisis period, resulting in almost 500 MW of demand reduction.
California cities also replaced millions of traffic lights with LED?s, each saving about 80 watts In more sophisticated
applications remotely controlled automatic electric load shedding options are available to residential, commercial, and industrial
customers. The utility provides economic incentives in the form of variable charges, and remotely interrupts the electricity
supply to particular appliances such as air conditioners in the customer?s premises. Research and product development is still
being carried out to determine optimum strategies for load-management acceptable to customers. In individual
commercial or industrial premises, sophisticated equipment is available which will, for example, automatically shut down temporarily,
one or more of the compressors in the air conditioning system during periods of excess demand. It is not suggested
that long-term plans be shelved for constructing additional power generating plants, but short term measures which have been
proved to be effective in other countries cannot be ignored.
The writer based in Herzliya, is an industrial engineer and business consultant
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