Electrical use by the average household in Nephi is highest between 8 and 11 a.m. every day, and the city has decided to do something to remedy the high-use period.
The city is now installing water heater controls.Earlier, city councilmen decided one way to cut the peak power demand is for power customers to sign up for load shedding. Since it costs more to produce or purchase electricity during the periods of peak demand than during off-peak hours, load management will help reduce costs, they said.
Nephi studies and those of other utilities indicate controlling water heaters has the greatest potential for reducing peak demand. Peak demand is the point of the day when the most power is used, and it determines the cost the city and the individual must pay for power, said Lee Fowkes, city electrical superintendent.
Water heaters consume great amounts of power, but they store hot water and, therefore can be shut off for short periods, which will help lower the peaks. Shutting the heaters off, even for short periods, reduces the peak and results in a more even distribution of electricity usage.
Fowkes said this benefits the city and the utility customer without noticeably affecting the availability of hot water.
Advances in computer and communications technology now make it cost-effective to control hot water heater circuits remotely through a small micro-computer system installed at the city office. The computer will control a special switch mounted on or near each water heater.
The city will be divided into districts and the radio-controlled switch will shut off heaters in one district at a time. After seven to 15 minutes the heater will be turned back on in one district and turned off in another. Only if the need is critical will heaters in several districts be turned off at the same time.
Nephi has about 1,100 electric residential water heaters. If the city were to control only 75 percent, or 825, the city could reduce the peak by 9.4 percent of the peak load. This would result in an annual gross savings of $83,000.
Fowkes said the city would like customers to try the program for at least 60 days. If they do not like it or think they have been inconvenienced, the water heater controller will be removed.
Customers who signed up by March 1 received a free water heater insulation blanket.
All customers signing up will get a $2 per month reduction in their electric bills a savings of $24 per year.