Out of your comfort zone

By Phoebe Sweet

Tuesday, Aug. 12, 2008 | 2 a.m.

On the hottest days in the Las Vegas Valley, Nevada Power turns down the air conditioning in 36,000 homes and businesses for hours at a time — and the utility wants to control many more.

Some valley neighborhoods got electric bills in June and July that included offers for free high-tech thermostats. More than 400,000 of those mailers went out last year.

The utility will install one of the AC and heating controllers and pay customers for the privilege of turning up those thermostats on sizzling summer afternoons.

The customers also get the power to manipulate their thermostats, via the Internet. Working late and want to try to save a little money by keeping your AC off for an extra hour? Just go online.

Nevada Power has offered these Cool Share thermostats since 2007, but it has a push on now to get more people to sign on.

The program shaves 65 megawatts — affectionately dubbed “nega-watts” — off peak demand in moments. That’s more power than is produced by the $250 million-plus Nevada Solar One power plant in Boulder City.

If the company’s approximately 807,000 residential customers all participated in the program, the company could, in theory, save as much as 1,450 megawatts of electricity at peak. That’s almost as much as would be produced by a $5 billion coal plant Nevada Power’s parent company, Sierra Pacific Resources, wants to build in eastern Nevada.

Conserving megawatts with the Cool Share program is much cheaper than building power plants or buying expensive summer-peak power. Plus, it’s lighter on the environment.

The company and customers save most by reducing energy use on the hottest days. So the Southern Nevada utility pays customers for the privilege of turning up their thermostats by as much as 4 degrees on summer afternoons.

Although conservation groups praise Nevada Power for its energy-saving programs, they also say the utility should do more to offset the Ely plant with less expensive conservation measures such as Cool Share.

“Energy efficiency is the cheapest, fastest way of meeting our energy demand,” said Lydia Ball of the Sierra Club. “So for up to a 4-degree difference, we wouldn’t have to pay for a $5 billion coal plant.”

Nevada Power started these efforts in 2001, when it installed remote-controlled switches on air conditioners outside valley homes. The company used the switches to turn down the power-sucking devices during peak power use times. About 20,000 customers enrolled in the program, then called Cool Credit for the credits customers received on their bills for participating.

But in 2007, after winning the approval of the state’s Public Utilities Commission, the company started using remote-capable indoor thermostats to control the AC units instead. The Internet capability means customers should be able to cut their gas bills in the winter too.

Since the Cool Share program began late last summer, the company has installed 16,000 of the thermostats in valley homes. There is a four- to six-week wait time between sign-up and installation because of the program’s popularity.

About 35,000 homes and 1,000 small businesses participate.

Here’s how it works: On 33 of the hottest days of June, July and August, the utility ratchets up the temperature in participating homes by 4 degrees or less for three hours — typically from 3:30 to 6:30 p.m. After the first four times it makes an adjustment, the utility pays participating customers $1 per air-conditioning unit for each additional time. In October, customers receive rebate checks for up to $29 per AC unit.

Participation is voluntary.

While at home, customers can use the thermostat to override the utility’s orders if it gets too hot inside, but if they do, they lose their payback for the day. When the utility raises a home’s thermostat by 4 degrees all at once, it take only one push of the button to override its orders. But sometimes the utility dials back 1 degree at a time on an hourly basis, which requires a customer to push the temperature adjustment button once an hour to override those changes.

There has been some attrition from the program — last year 240 customers bailed out. Customers with the older technology — throwbacks from Cool Credit — are more likely to leave because they can’t control the AC dial-back if they happen to be home in the afternoon or if their house gets too hot to bear, said program manager Michael Brown.

He acknowledged that the more recent technology has had its hiccups too. For example, Cool Share small-business customer Lauri Gibson, owner of Jersey Mike’s Subs on South Durango Road, saw temperatures in her store rise to above 100 degrees one day in June when the thermostat shut down her AC and wouldn’t turn it back on. She had to shut down the shop for the day, but the next morning a Nevada Power employee came to the store to replace the system.

Brown said any program in which thousands of pieces of technical equipment are installed in homes is bound to have some problems.

But since that one disastrous day in June, Gibson says, she’s loved the programmable thermostat, which is easy to override on very hot days.

“Sometimes it gets a little warmer, but you just push the button if it gets too hot,” Gibson said.

She said she will have to look back at last year’s bills to tell, but hopes to save some money this year.

Nevada Power’s adjustments can save the average residential customer $12 to $15 per air conditioner over the summer, Brown said.

Although $15 might seem like a pittance in the land of the $400 August electric bill, Brown said customers who turn up the temperatures in their homes while they’re not there — even when Nevada Power isn’t doing it for them — can save an additional 15 percent to 20 percent on their bills. Studies have shown that cooling a house again after turning up the temp 4 degrees for three hours still saves energy overall.

And there are advantages to the utility, of course.

Reducing the amount of power it must provide on the hottest days saves Nevada Power money in several ways. The company buys lots of power on the open market during the hottest days, when it is most expensive. And natural gas costs most when demand is high during summer. Cutting peak demand saves on fuel and purchased power costs, which are passed on to consumers.

Shaving megawatts from peak demand also lets the utility avoid expensive infrastructure improvements in areas where older power lines can no longer deliver enough power for growing populations.

“We’ve been trying to target single-family homes ... in areas where we have distribution systems that are approaching design limits,” Brown said. “Reducing power consumption in certain areas at peak will avoid spending millions ripping up the street to put in more lines.”

So savings to the utility and customers dwarf the cost of the thermostats and installation, Brown said.

The utility also is running a small pilot program testing Home Energy Displays — high-tech thermostats that give customers real-time feedback on how much energy they’re using, how much that energy costs and ways to reduce their bill. Although the company can’t control these thermostats remotely, they’re testing whether the feedback provided to customers on the thermostats, online and in new more detailed bills will prompt consumers to reduce their power use on their own.

As technology advances, so will the ways Nevada Power coaxes and cajoles customers into saving energy.

But for now, Christine Lu is doing her part with the technology offered today. She signed up for Cool Share not only for her Summerlin home, but for 11 rental properties she owns.

She said installation was quick, a Nevada Power employee gave her a tutorial on how to use the device, and she’s saved money on her summer bills already.