People get global warming. Now, they're asking: "What can I do about it?"

Actually, quite a lot, according to speakers at an all-day public conference on the topic at the state Capitol yesterday.

From light bulbs to photovoltaic cells, the technology to help reduce greenhouse gas emissions is rapidly becoming more cost-effective and widely available, speakers said. And more alternative-fuel sources are waiting to take off, including wave, wind and even algae power.

"There's a flood of interest in this now and things are changing very quickly," said Jeff Mikulina, director of the Sierra Club's Hawai'i chapter. "We just need to get the word out so people can know what they can do to help."

But statewide strategies for reducing greenhouse gases, which are causing the climate to warm, will take a combination of regulatory action, financial incentives and increasing education, several participants said.

Yesterday's conference, organized by Hawaiian Electric Co., was designed to bring local experts together to discuss ways utility companies and others can help meet a new mandate passed by the state Legislature to reduce greenhouse gas emissions to 1990 levels by 2020. The Public Utilities Commission also has ordered a year-long review of ways Hawai'i will meet its power needs in coming years as oil supplies decline.

"We must act expeditiously and we must act with skill in terms of how the greenhouse gas law will impact our way of life," said HECO Vice President Robbie Alm. The bill passed by the Legislature, which has not yet been signed by Gov. Linda Lingle, does not spell out how the state should meet the new mandate.

Many alternative fuel technologies will become more cost-effective in the coming decade, said Dave Rezachek, head of the Hawai'i Renewable Energy Association. They include ocean thermal energy conversion, seawater air-conditioning, biofuels, winds, wave power and photovoltaic cells, he said.

"If we produce just once 100 tons (about 1.2 million BTUs per hour) of seawater air conditioning, that's the equivalent of taking 50,000 SUVs off the road or buying 115,000 Toyota Priuses or installing 123,000 solar water heaters in Hawai'i," he said.

In the meantime, people who want to help can best do it by reducing energy in their own homes, said Brian Kealoha, senior vice president of Energy Industries, a company focusing on efficiency, generation and renewable energy.

"Energy efficiency is the low-hanging fruit. All the other alternative fuels don't add up together now to equal the potential for energy savings," Kealoha said. The biggest savings come from switching over to compact fluorescent lamps, installing solar water heaters and buying energy-efficient appliances, he said.

Reach Mike Leidemann at mleidemann@honoluluadvertiser.com.