In some areas, energy consumers are able to save money by timing their usage of appliances such as dishwashers, washing machines, and hot-water heaters to coincide with when low electricity rates. Generally, this means avoiding the 6 a.m. to 10 a.m. and 5 p.m. to 9 p.m. periods. This strategy is possible when utilities engage in time-of-day pricing. It is seen now in more than a dozen utilities in seventeen states.

Consumers can track hourly costs through the Internet or on specialized meters. In the future, it is anticipated that appliances will be computerized so they can switch on and off automatically as energy prices change.

The reductions in electricity usage in peak periods means that the utilities do not have to pay exorbitant rates for additional power on the spot market or finance costly new power plants. For example, California utilities usually pay less than $100 per megawatt-hour, but last July had to pay over $700 on the spot market on some hot days. Savings for utilities translate into lower prices for consumers. Real-time pricing can also help avoid blackouts. It is estimated that if time-of-day pricing were introduced nationally, it would save $10 to $15 billion annually, and remove the need to build 200 power plants.

However, real-time pricing will not spread very quickly. The capital investment in computer networks and special meters would be expensive. Also, state regulators tend to be conservative, fearing that the elderly and poor would be disadvantaged, as they would find it more difficult to shift their energy usage.

(Updated August 1, 2001)