With temperatures on the rise, electric utilities in the region are cranking up programs to induce customers to curb their air-conditioner use during peak summer days.

Peco Energy Co., the Philadelphia utility, is heavily promoting its Smart A/C Saver program, which pays residential customers as much as $120 a year to allow the utility to cycle their central air-conditioning units off during periods of peak demand. About 80,000 customers have volunteered to allow Peco to install a radio-controlled switch on their outdoor condenser units.

Public Service Electric and Gas Co. and Atlantic City Electric Co., which serve customers in southern New Jersey, have similar programs. The New Jersey utilities pay a smaller bonus to customers, but they offer a programmable thermostat as part of the package, allowing customers to better manage their energy use year-round.

The utilities in both states are under pressure from regulators to curb demand during peak periods, which reduces the need to build more power plants and helps reduce consumer costs. Under a 2008 Pennsylvania law, Peco and five other large utilities must reduce peak demand 4.5 percent by May 2013 or face big penalties.

Across the nation, the air-conditioner cycling devices have become a mainstay for utility load-shedding programs. Utilities typically toggle the air-conditioner condensers on and off in 15-minute intervals. Multiplied by thousands of customers, the amount of energy saved for each utility is comparable to the output of a small power plant.

Utilities claim the cycling does not create discomfort for most customers. PSE&G says customers can expect temperature increases of between 2-5 degrees during the "conservation events." Atlantic City Electric tells its customers they can expect increases of between 1 and 3 degrees. The temperature change depends upon how well insulated a home is, and how much it is exposed to the sun.

"There are many customers who participate who don't notice the temperature changes," said Catherine Engel Menendez, Peco's spokeswoman.

But many customers of Baltimore Gas and Electric Co. last year complained about soaring temperatures in their homes because of air-conditioner cycling when a heat wave gripped the East Coast on July 22, according to a report in the Baltimore Sun.

Peco began its Smart A/C program in 2010 and last year declared only two "conservation" events, on July 12 when the temperature reached 93 degrees and on July 22, when it reached 102 degrees at Philadelphia International Airport. Peco set an all-time peak demand of 8,983 megawatts at 1 p.m. on that day, before it initiated its load-shedding program.

Peco is now able to reduce load 34 megawatts by cycling air-conditioners, Engel Menendez said. But that number is expected to grow as more customers get the devices installed.

According to Peco's conservation plan filed with the Pennsylvania Public Utility Commission, the utility aims to shed 61 megawatts by next year by cycling residential air-conditioners. Including large commercial and industrial customers, Peco aims to have 355 megawatts of power it can shed to meet the state mandate.

The utility is currently trying to boost residential enrollment with an ad campaign whose headline cuts directly to the bottom line — "Want to save $120 this summer?"

Customers who sign up by April 30 will get the control devices installed before the summer cooling season, said Engel Menendez, so they will be able to collect the full bonus, which is paid out in $30 monthly credits for each of four summer months.

Last year, the utility paid out $8.6 million to Smart A/C customers. The air-conditioner program is just one element of a complex energy conservation package that is costing Peco ratepayers $342 million over four years.

The New Jersey utilities, which are also mandated by state regulators to reduce demand, have had an air-conditioner curtailment program in place for more than 20 years. But the New Jersey programs were ramped up in 2009, when the utilities began offering the programmable thermostats, which allow the utility to wirelessly toggle the air-conditioners on and off from the thermostat inside a customer's home, rather than a switch attached directly to the air-conditioner unit.

Atlantic City Electric, which has enrolled 23,000 customers in its Energy Wise Rewards program, offers customers a $50 signing bonus to get the programmable thermostat, but no additional payments when power is curtailed, said Bill Yingling, the company's spokesman.

PSE&G, which has enrolled 90,000 of its 2.1 million customers in its Cool Customer program, offers customers a one-time $50 bonus for getting the programmable thermostat that also allows the utility to take control of their air-conditioner.

For customers who opt for a cycling switch on their air-conditioner instead of the thermostat, PSE&G will pay a $4 credit on their electric bill for each of the four summer months plus $1 for each cycling event. The utility can initiate up to 20 cycling events per year, but the most it has done in recent years was three events in 2008.

PSE&G estimates it currently can shed about 65 megawatts of electricity by reducing air-conditioner usage.

Contact Andrew Maykuth at 215-854-2947 or amaykuth@phillynews.com or follow on Twitter @Maykuth.