President Obama’s $787 billion economic stimulus package should be putting one question at the forefront of every homeowner’s brain: How can I tap into the billions of dollars designated in the plan for green building, retrofitting, energy efficiency and renewable energy products?

The easy answer is through tax incentives. The law increases tax credit for certain energy-efficient home upgrades — such as solar water heaters, solar panels and geothermal heat pumps — from 10 percent to 30 percent through 2010.

There’s also the $5 billion Weatherization Assistance Program, which provides up to $6,500 per low-income family (by federal guidelines, about $44,100 for a family of four) to weatherize and improve the energy efficiency in their homes.

And there are billions of dollars in stimulus funds to be distributed in the next few months by local and state governments through the Energy Efficiency and Conservation Block Grant (EECBG), a federal program authorized in 2007, but unfunded until now.

“There are more than 2,000 communities that will receive money,” says Jason Hartke, director of advocacy and public policy for the U.S. Green Building Council. “This summer we’re going to see an explosion of new programs.”

Cities everywhere are scrambling to turn in their proposals to the Department of Energy, but municipalities like Berkeley, Calif., and Babylon, N.Y., are already way ahead of the curve in providing financially sustainable models for home retrofitting and upgrading.

If you live in, say, St. Louis, why should you care about Babylon and Berkeley? Because their innovative programs can be a road map for citizens in other cities to save thousands of dollars while making big-ticket, energy-efficient home improvements.

Berkeley’s FIRST (Financing Initiative for Renewable and Solar Technology) program, part of Berkeley Climate Action, allows property owners to use a state-approved solar installer to retrofit their homes with the most appropriate solar solution. The city pays for the installation up front via bond funding but adds an assessment to the property taxes, which will be paid off by the owner over a period of 20 years.

“We want to provide incentives for comprehensive audits and serious home improvements,” says Neal DeSnoo, energy program officer for Berkeley’s Office of Energy and Sustainability. “We don’t want to just incent people to screw in CFLs.”

The average cost for a new home solar system is about $22,000, which amounts to about $1,150 extra in property taxes per year. But add the 30 percent tax break for the installation, in addition to rebates from the local energy company, plus the increased energy efficiency after the system has been installed, and the homeowner almost always ends up in the black.

Last November the town of Babylon, population 211,792, kicked off its Long Island Green Homes Program, self-financed by a partnership with the waste-to-energy firm Covanta. (Babylon sells its solid waste to Covanta, which has raised $2 million for the Green Homes pilot program. In addition, Babylon will also receive $1.54 million from the EECBG.)

The Babylon program works like this: The property owner gets a home-performance evaluation from a pre-approved private contractor. The town will pay up to $12,000 to perform the home upgrades; the property owner pays it back to the city in the form of a monthly assessment, which includes an additional 3 percent administrative fee. The assessment is almost always zeroed out by the energy savings.

So far, 98 homes have been retrofitted or are awaiting a retrofit, with an average cost of $6,800 per household and an average annual savings of $920. The average increased efficiency has been 28.5 percent. After 84 completed projects, $1.6 million remains in the $2 million initial fund.

The program has been so successful that the city has started The Babylon Project, a nonprofit designed to assist municipalities in formulating their own residential Energy Efficiency programs.

“Clearly all localities have their respective characteristics,” says Dorian Dale, the town’s energy director. “But The Babylon Project website will provide both the model and an interactive component for the sharing of best and worst practices.”

You may not be directly involved in your city’s policy-making machine, but if you are a homeowner interested in getting a return on your energy-efficient investment, heed the advice of Neal DeSnoo: “Find out now who is responsible for your community’s EECBG funds.”