Energy futureSmarter electric grid could be key to saving power, II

Published 6 May 2008

Power providers and technology companies are making the electric grid smarter; it will stop being merely a passive supplier of juice; installing smart controls in homes would allow consumers to decide how much energy they need at what price

 

U.S. utilities are interested in
creating a smarter grid as much as their Canadian counterparts. A Maryland utility will have its own version
of the device now used in Milton, Ontario. Most of the homes will get
3-inch-high orbs which will glow different colors to indicate the price of
electricity: red instead of their usual green, for example, during critical
peak periods. Even this, though, will probably be but a primitive step. AP’s
Brian Bergstein writes that eventually, the smart grid will
let rates fluctuate even more dynamically, depending on conditions. That
already happens in wholesale electricity markets, in which power suppliers buy
energy from power producers. Now that would extend to the retail level. The
price of electricity would dip when demand is softest, typically at night or on
mild days, and rise in periods of strain. There is only one problem.
“Consumers are not sitting at home waiting for the latest signal from the
power grid,” says Rob Pratt, a scientist with the Department of Energy’s
Pacific Northwest National Laboratory. “To get the kind of widespread
response that we’d really like to have, keeping it automatic is real
important.” In other words, appliances designed to interact with the
smarter electric grid will adjust themselves.

Pratt’s
lab has already built and tested controllers that can make it happen. During
the next decade, Pratt expects homes to get appliance controls with a sliding
scale. At one end people could choose something like “maximize my ease and
comfort.” At the other, “save me the maximum amount of money.”
The highest-conservation settings might lead dishwashers to start only when
electricity prices are at their lowest, or when wind power has kicked on. When
Pratt and colleagues tested aspects of this in 112 homes in Washington state, they determined the
average household’s electricity bills would drop 10 percent.

It says a
lot that conservation would be encouraged by the very companies that make money
off the use of electricity, but they have no real choice. Electricity use per
home rose 23 percent from 1981 to 2001, according to the Department of Energy. The
Census Bureau says 46 percent of single-family homes completed in the United States in 1975 had air conditioning. In
2006 that was 89 percent. Meanwhile, meeting that demand is getting trickier.
Raw materials that fuel power plants are soaring in price and being eyed more
skeptically by regulators concerned about air quality and greenhouse gases. This
is even before the next U.S. president, as seems likely,
supports caps on carbon emissions. “We just can’t keep building more coal
plants,” says Roy Palmer, head of regulatory affairs at Xcel Energy. Until
some bountiful and clean power source can be delivered cheaply, electric
utilities are pressured to extend the generating capacity we already have.

The
effects of well-chosen reductions in usage — an idea known as “demand
response” — can be huge. A mere 5 percent improvement in U.S. electric
efficiency would prevent 90 large coal-fired power plants from having to be
built during the next twenty years, according to Jon Wellinghoff, a member of
the Federal Energy Regulatory Commission (FERC) who advocates demand response.
Demand response is not new, but it has existed in low-tech form. Utilities in
capacity crunches would call companies and request that they do something to
help, like idling an assembly line for a few hours. In some states, residents
can get rebates if they let the utility trigger radio transmitters on their air
conditioners that cycle the chillers off for a few minutes in strained summer
hours. Now though, technology can do demand response in a more sophisticated
way. Companies such as Boston, Massachusetts-based EnerNOC have built software and sensor
networks that can remotely dim lights or raise refrigerator temperatures inside
businesses, in an instant. For homes, upgraded electric meters can offer
near-real-time feedback on energy use. New generations of appliances and
thermostats can coordinate with each other and electric meters over in-home
wireless networks.

The problem is figuring out how to pay for it
all. The equipment in Milton’s tests costs more than $1,000 per house. This
will come down with larger-scale efforts, and utilities will save money as
networked meters free them from sending out human meter readers each month. For
bigger smart-grid investments, however, energy companies generally want
regulators to let them recoup the costs through higher electric rates. This can
get problematic in a hurry.