Hourly energy use data, now online.

I've never paid much attention to my electric meter. For most of us, it's just that box on the side of the house with a small white disk spinning inside, keeping track of our energy use. But over the next three years, all the meters of PG&E customers will be getting a major upgrade to a new, digital SmartMeter.

I met one customer, Ken Kube in Castro Valley, whose meter has already been upgraded. Since the new meters track his home energy use digitally, Kube can log into his PG&E account and see his real-time energy use. On one level, it's really the ultimate tool for parents who like to remind their kids to turn out the lights. But it's also a powerful conservation tool. Kube could see how much energy he uses at night, when his appliances are drawing power in stand-by more (what's known as "vampire" power).

These meters are just a small piece of the puzzle when it comes to a smart grid. Just what the smart grid is depends on whom you ask, but most people agree it comes down to one thing: communication. The energy landscape is changing rapidly. In addition to increasing demand, there's more renewable power like large-scale solar and wind coming online – which are often far from urban areas and are available intermittently. There's also small-scale solar on building rooftops – which means energy consumers are becoming energy producers. There will also be plug-in electric cars, which need to draw power from grid.

To manage all this, utilities and grid operators need more information than they have. And that's where meters come in. But as Kurt Yeager of the Galvin Electricity Initiative describes, it's a huge networking challenge – and a huge market opportunity.

Audio clip: Adobe Flash Player (version 9 or above) is required to play this audio clip. Download the latest version here. You also need to have JavaScript enabled in your browser.

A number of companies have jumped into the smart grid market as a result, from Silicon Valley start ups to international corporations. As Eric Miller, the Chief Solutions Officer for Trilliant describes, managing the information flow in smart grid will be the biggest challenge.

Audio clip: Adobe Flash Player (version 9 or above) is required to play this audio clip. Download the latest version here. You also need to have JavaScript enabled in your browser.

Other smart grid companies are banking on the consumer market. Google is developing the PowerMeter, an online tool that tracks home energy use. They're partnering with GE, who is positioned to work with utilities, with its meter technology, and with consumers, with smart appliances, as Sunil Sharan, the Director of the Smart Grid Initiative explains.

Audio clip: Adobe Flash Player (version 9 or above) is required to play this audio clip. Download the latest version here. You also need to have JavaScript enabled in your browser.

More on the smart grid: check out the Smart Grid at Home radio report and a slideshow of grid technology, old and new.

If investment is any guide, California's renewable energy companies are leaping into the new year. Investors poured billions of dollars into clean tech in 2007 to catapult green technologies to market. In the first three quarters of 2007, U.S. venture capital firms invested $2.6 billion in clean tech companies. That's compared with $1.8 billion for all of 2006.

Over the past year, a few types of renewable energy have seen a lot of attention. One is solar thermal power – a form of energy that hasn't been built in decades. In the 1980's, several large solar thermal plants were built in the Mojave Desert. The technology sounds pretty simple: Mirrors are used to reflect sunlight onto on a liquid or substance, usually water. The water is super-heated by the sun and bingo – becomes steam. The steam is then used to turn large turbines. California utilities are starting to look these plants again, and companies like Ausra in Palo Alto and BrightSource Energy in Oakland are benefiting.

Thin-film solar is another area that has gotten a lot of buzz. Only a few companies are currently selling thin-film. While today's panels aren't quite as efficient as silicon solar cells (the kind you see on rooftops), many are hoping they'll be cheaper and stronger. That makes it easier for companies to manufacture Building Integrated Photovoltaics – building materials like roof tiles with solar built-in.

Energy efficiency is another area companies are getting into, and in this case, it's energy management. Several companies are working on devices would manage energy use in your home. They could feed power from a solar system back to the grid and turn on your appliances late at night, when power is cheapest. PG&E is taking a step forward by installing Smart Meters in homes now – new digital electric meters that provide real-time data to customers and utilities. After that comes real-time electricity pricing for those who want it, meaning it’s not just how much you use, it’s when you use it.

You may listen to the "The New Clean Tech" radio report online, as well as find additional links and resources.

Lauren Sommer is an Associate Media Producer for QUEST.

latitude: 37.2647, longitude: -121.79