Listening to the Price of Power: New Thermostats Could Save Billions

Aug 12, 2009 By Gordy Slack
Berkeley engineers are working on a smart home thermostat that could save energy costs and resources by using settings to crank the air conditioning down at night or when occupants are out. First-generation devices, which appeared during the 1970s oil crisis, are often not programmed because owners find them too confusing. PHOTO COURTESY THE RESEARCHERS

A new generation of inexpensive programmable thermostats with the capacity to communicate may provide a simple and versatile tool for addressing California’s complex, billion-dollar summer peak energy demand problems. Engineering professor David Auslander—working with utility companies, engineers and policy wonks—has created a new set of design rules for the programmable communicating thermostat (PCT) that could help pave the way for greater energy efficiency in homes.

Energy specialists have long known that programmable thermostats (PTs) have the potential to save homeowners money, reduce the need for new and shrink the amount of pollutants and climate-altering CO2 pumped into the atmosphere. Originally deployed during the oil crisis of the 1970s, PTs and their digital descendants permitted consumers to instruct their thermostats to turn down the air conditioning at night when occupants were sleeping and during the day when no one was home.

“We expected those early thermostats to save a lot of money and energy,” says Ronald Hofmann, a senior advisor for the California Institute for Energy and the Environment and advisor to the California Energy Commission (CEC), which funded Auslander’s research. “But only if people used them. And unfortunately, fewer than 20 percent of Californians took, or take, the time to program their thermostats.”

, a government-backed program that gives efficiency ratings to appliances, last year withdrew its “high” rating from PTs because their owners either find them too confusing to set, or just don’t bother to try, says William Burke, the lead grad student on Auslander’s team. That reluctance and confusion cost California and energy consumers billions of dollars each year.

The new approach addresses this problem by augmenting the communication component to the PCT, making these devices more user-friendly, responsive to pricing and independent of specific communications media. In developing the new design, Auslander and co-PIs, engineering professors Paul Wright and Richard White, worked closely with state regulators, private industry and policy experts.

Some time over the next five years, California’s major utility companies will install in homes new electric meters that can record usage on an hourly basis. The new communicating thermostats would receive hourly updates about electricity prices through a built-in module, Hofmann says; consumers would be able to program them to automatically minimize cost while maximizing comfort. Data entering the PCT can come from the utility through the meter, from the Internet through a router or over the airwaves.

If the user interface were easy enough to use, Burke says, customers could save money by programming the thermostat not only to regulate air conditioning and heating, but also to communicate with appliances, directing them to work when electricity is cheap and rest when it is dear. Burke, a fifth-year doctoral student in mechanical engineering focusing on control of intelligent systems, is developing algorithms that could help consumers simply profile their consumption habits and priorities and let the software devise the best strategy for implementation.

Alternatively, consumers could let a third party program their thermostats remotely, via the Internet, and pay for the service with some fraction of the savings gained by using less electricity, Hofmann says. Essentially, you would be downloading cost-saving “lifestyle” schedules and strategies for your thermostat and other appliances.

The most dramatic savings to the state may come long before the utility companies succeed in actually installing smart meters, though. The new thermostats could receive FM-radio data system (RDS) transmissions, for instance, informing users when the grid is approaching peak load. This happens only on a few hot summer days each year, but meeting the demand is very expensive to the state.

California's peak daily power usage is generally somewhere between 35,000 and 40,000 megawatts of electricity a day, generated mostly by a combination of nuclear plants, hydroelectric and combined-cycle natural gas-fired plants. But on those few sweltering days, when air-conditioning consumption is high, the utilities must generate 50 percent more electricity by firing up older, dirtier and more expensive fossil-fuel power plants.

Sometimes the capacity to meet this demand even has to be bought at exorbitant cost from outside the state. On extreme occasions, as during the 2001 heat wave, rolling blackouts must be imposed, taxing not only the state’s coffers but also its ability to do business, its reputation and its quality of life. The cost of reserving “peaker” plants for only a few hundred hours of service a summer can be more than one billion dollars annually.

A better strategy, the CEC believes, is known as demand response: using communications and information technology, utilities can signal consumers’ thermostats that the grid is stressed and ask them to reduce consumption. To speed the transition to residential demand response, the CEC backed Auslander’s project to include the creation of design standards that would work for industry, consumers and utilities.

A customer could set his or her thermostat so that, when it receives a warning from the utility that the region is nearing grid capacity, the PCT would automatically raise its temperature setting by a few degrees. If they choose to pay the price, customers can ignore the signal and set their own thermostat; they, not the utility or the government, retain the final say in the temperature set point.

Most customers, Auslander predicts, will gladly cooperate by adjusting their set points. And the combined effect of one degree or two of adjustment spread across large regions will often be enough to avert rolling blackouts.

“While it might seem invasive to some,” he adds, “it’s a lot less invasive than having your lights go out and your computer shut off.”

Source: UC Berkeley, Innovations, Marketing and Communications Office

Explore further: Green technology saves energy and boosts profits, productivity in factories

add to favorites email to friend print save as pdf

Related Stories

Electricity blackouts: A hot summer topic

Aug 09, 2006

It is a common misperception that blackouts are caused by power shortages, but in any given year, about 90 percent of the power outages that customers experience are due to problems with the local distribution ...

Purdue studies office building power

Jan 18, 2006

Purdue University engineers say they've developed a method of "pre-cooling" small office buildings, cutting energy consumption during times of peak demand.

CSIRO Builds Smart Energy System

Mar 22, 2006

CSIRO technology will help to reduce black-outs and improve the reliability and efficiency of the electricity grid while reducing greenhouse emissions. It will also complement smart electricity meters promising consumers ...

Recommended for you

Preparing for a zero-emission urban bus system

3 hours ago

In order to create a competitive and sustainable transport system, the EU must look to alternative fuels to replace or complement petrol and diesel. Not only will this reduce transport emissions but it will ...

Exploring the value of 'Energy Star' homes

3 hours ago

The numbers in neat columns tell—column by column, page by page—a story spread out across Carmen Carrión-Flores' desk at Binghamton University. It's a great story, she says; she just doesn't know how ...

Toward a networked energy future

Oct 29, 2014

February 1, 2050, is a good day for German electricity consumers. The breeze off the north coast is blowing so strongly that offshore wind farms and the wind turbines on land are running non-stop. Since it's ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

david_42
5 / 5 (1) Aug 13, 2009
Good to see that California is thinking about maybe doing something some time that's sort-of like a Nevada program I participated in in the 1980s.
COCO
not rated yet Aug 18, 2009
we got that technology - already - have a company selling a system - REGENENERGY - with hard numbers to back up claims - come north my thirsty friends

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.