Hawaii is preparing to connect into a two-way electrical grid that should usher in the future of “;green”; energy. As the new system expands, prices should come down and lure regular homeowners to produce more electricity than they use, and get paid for the difference. The wave of the future requires careful preparation.

The state Public Utilities Commission gave its approval last week to the launching of a program that will allow small and midsize energy projects to sell renewable electricity that's left over from their use to “;feed in”; to Hawaii's power companies. The commission's 128-page ruling leaves rates to be decided later.

Such a system has revolutionized Germany and Spain. Several states have signed on. Gainesville, Fla., and parts of Wisconsin have such a system; Oregon is set to begin its feed-in tariffs in April. In Vermont, the first state to enact such a system, financial incentives attracted more than 200 projects last week with more than 14 times the total solar generation of electricity than was expected. California Gov. Arnold Schwarzenegger this month approved measures doubling the solar facilities engaged in the systems and offered incentives to households and businesses to hook up.

“;Your home can now become a power plant,”; says Jeff Mikulina, executive director of the Blue Planet Foundation, “;and that signals a turning point in Hawaii's energy trends.”;

The system has the full support of Hawaiian Electric Co., which has agreed to work toward implementing feed-in tariffs. It has signed on to the Hawaii Clean Energy Initiative, with a target of 40 percent of the state's energy needs to be fulfilled by renewable sources by 2030.

The move toward creating more than enough renewable energy is likely to be made by businesses in the near future, consisting of bulky solar panels atop roofs or on the ground. As technology advances, that will change. Companies are now producing shingles, tiles and other building materials with photovoltaic cells sealed within.

The cost of a residential solar system, creating about 3,500 watts, is estimated at $35,000. However, the federal government offers a 30 percent tax credit and Hawaii provides a 35 percent credit or $5,000, whichever is less. Also, the cost is likely to decrease with technological advancement and growth of the market.

President Barack Obama this week announced an ambitious energy grid modernization program with matching grants to utilities and other partners to foster the growth of renewable energy sources like wind and solar. It includes a $10.7 million Hawaiian Electric project to automate circuits feeding eastern Oahu.

“;At this moment,”; Obama said, “;there's something big happening in American, when it comes to creating a clean-energy economy.”;

If done right, that will be especially big in Hawaii, the only state that relies largely on imported oil for its electricity.