WASHINGTON DC – A year ago, everybody in green tech wondered where they’d get money to survive the financial crisis. The answer for many was Washington.

The change with the Obama administration’s Department of Energy has been nothing short of dramatic, CNET News.Com reported. Tens of billions of dollars in grants and loans have started to flow toward plug-in vehicle manufacturing, smart grid projects, and solar and wind farms. Behind it is not only a priority to address energy and environmental problems, but a concern that the U.S. will lose out in the global race for clean-energy innovation.

What happens after the stimulus money runs out is a gaping question, but the next three years will see real changes in technologies that touch people’s everyday lives – cars and homes.

In 2009, we got a taste of the future as automakers rolled out their plans, prototypes, and near-production models. In addition to the much-hyped Chevy Volt, there was the Nissan Leaf, an all-electric sedan that its maker says will have a range of about 100 miles, along with several other electric car variants.

On the home front, the buzzword of 2009 was “smart”- as in smart appliances, smart meters, and smart grid. Utilities launched trial projects that should lead to millions of U.S. homes getting “smarter” in the sense that the electricity meter will be able to do more than just tally kilowatt-hours. But these utility-run programs are just trials. What remains to be seen is whether consumers and businesses will begin to monitor their energy use in real time and take steps–as simple as programming a thermostat or turning off video game consoles- through home energy monitoring displays, many of which can be made to work without smart meters.

Of course, there are other reasons to invest in a smart grid. With digital communications overlaid onto the existing grid, utilities can use energy more efficiently, prevent costly outages, and add more solar and wind power. But there’s a missing piece: energy storage. Large-scale storage of many kinds–compressed air, flow batteries, and gigantic lithium ion batteries–became a hot area in 2009 for both utility-scale and vehicle storage.

Money continued to flow from the private sector, too, with green-tech venture capital becoming the largest investment category this year. But there were some hiccups, with start-ups closing down for lack of funds, including an algae fuel company and battery maker.

There will be more failures, despite the injection of stimulus money around the world. Even though green tech is a hot venture-capital area, there’s a growing understanding of the difficulties–both financial and technical–in getting energy technology into the marketplace. Look no further than biofuels. After years of promises, making liquid fuel from feedstock other than corn won’t happen at large scale for several more years.

As usual, what happens next from the federal government is a big unknown. Will there be a federal or international mandate to put a price on carbon emissions? Will subsidies to promote clean energy technologies drop off, as they did in the past with devastating effects? Will consumers take advantage of tax breaks for home weatherization programs?

Entrepreneurs and investors will no doubt continue to lobby at home and in Washington to get their nascent industries on better footing. But in the end, many are simply back at work inventing the future of energy.

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