The picture of our carbon-free energy future is often depicted by a sea of solar panels shimmering in the sun, or orderly lines of giant white windmills covering a hillside: large structures that capture nature's gifts.
But an increasingly important energy resource is little more than a digital electric meter.
And this meter will make possible the widespread use of electric vehicles, according to representatives of Rosemead-based Southern California Edison.
Automakers unveiled more than a dozen
production-ready, plug-in electric and hybrid-
electric vehicles at the North American International Auto Show in Detroit this month, many of which will be on dealership lots between 2010 and 2012.
Several automakers, including Ford, have partnered with Edison to ensure those cars can get their electricity from somewhere.
"When we look at the electrification of vehicles, there are a lot of different issues involved," said Ford spokeswoman Jennifer Moore. "There is the technology, there is the market, but there is a bigger question than that: It's also very much about connecting to the nation's (electrical) grid and where the electricity comes from."
With a national electrical system that at times and places is severely strained and in need of expansion, the last thing anyone wants is for electric vehicles to be powered by building more emission-producing power plants.
Edison's answer: new meters.
The idea is for electric cars to take advantage of "off-peak" hours of low energy demand late at night, when the lights are out and TVs are off, but power plants are still producing, said Ed Kjaer, director of electric transportation at Edison.
"We have a huge amount of generation capacity in the U.S.," Kjaer said. "But it is an inefficient system. You have to build power plants to meet the peaks when every single air conditioner is going full blast."
Although some types of power generation can easily be turned off and on, others - such as nuclear and wind - continue producing whether the electricity is used or not.
Studies have found that electric vehicles could be charged with electricity produced under the current system, if done at the right time, agreed National Resources Defense Council scientist Simon Mui.
It might seem that simply plugging in your Chevrolet Volt or Ford Escape before bedtime would do. But increased use of electric vehicles could lead to everyone plugging in at the same time, peaking demand and complicating things, particularly if electric vehicles take hold of entire neighborhoods, as car trends often do, Kjaer said.
So instead, Edison and auto manufacturers are turning to "smart metering" technologies. Such technologies allow consumers and, potentially appliances, to be aware of how much electricity is being consumed everywhere so that they can try to consume when other people are not.
Although traditional meters do nothing more than report to electric utilities how much electricity is consumed in a given amount of time, smart meters give real-time information and allow for two-way communication between the power grid and consumers.
This would allow utilities to stagger when electric cars are charging, or charge up power all at once if generation is high.
Plug-in hybrids require about as many annual kilowatt-hours of power as two or three plasma TVs or air conditioners, according to Mark Duvall, director of electric transportation for the Electric Power Research Institute.
Edison figures it will have smart meters installed in all its customers' homes by the end of 2012, in compliance with California Public Utility Commission requirements.
Smart meters have uses far beyond electric vehicles. Appliances, such as dishwashers or dryers, could also react to real-time electricity use before deciding when to power on.
Because wind typically blows harder at night, environmentalists are particularly excited about its potential on such a system, Mui said.
To be sure, smart meters alone will not produce highways full of electric cars. The sticker prices of all-electric and plug-in hybrids will be well beyond the reach of average consumers for several years, hardly dipping below $30,000, Kjaer said.
Early support from those who can afford them, as well as the federal government, will be necessary, he said.
The economic stimulus package before Congress could include incentives for buyers of electric vehicles and electric- vehicle-battery manufacturers.
While it is not the first time a future of electric cars has been on the horizon, industry experts say it's real this time.
"I have never before felt that we were at this point," Duvall said. "The auto industry is aligned, the public is aligned, even the president is aligned. He even knows what a plug-in hybrid is."
"We are dealing now with a perfect storm," Kjaer said. Energy security, the politics and marketing of oil and concerns about climate change are creating an unprecedented global push toward electric vehicles.
"Even during a time of unprecedented global turmoil, the industry is not backing off," Kjaer said. "Because of those three drivers. Most automakers realize that electrification is inevitable."
And President Barack Obama told the country during his inaugural address: "We will harness the sun and the winds and the soil to fuel our cars and run our factories."
And we will use meters.