Hawaii has to be more aggressive than the rest of the country about switching to renewable energy sources. And, according to volunteers at the Natural Energy Lab of Hawaii Authority on the Big Island, the state is doing just that.

John Deveau, who worked in nuclear energy in Connecticut for more than 34 years before volunteering to give an in-depth energy lecture to visitors at the lab on Tuesdays, said the state aims to get just 30 percent of its energy from fossil fuels by 2030. That’s a sunstantial drop from the almost 90 percent dependence on imported oil presently.

Electricity in Hawaii costs an average of 42 cents per kilowatt hour, more than four times the average cost of power on the mainland.

Reaching the 70 percent alternative energy portfolio standard, which includes goals for renewables and for conservation, will be a challenge, however, especially since the most densely populated islands using the most power have the least space for wind turbines and solar farms. There are more than 1 million people living on the island of Oahu, home of Pearl Harbor and the state’s capital Honolulu.

“We’re in really good shape for ourselves here on the Big Island,” Deveau said.

Between 30 megawatts of wind power, a major geothermal plant drawing energy from the superheated Kiluea volcano and significant distributed rooftop solar power generation, the island is already obtaining almost 40 percent of its energy from renewable sources. It doesn’t hurt that the island’s population tops out under half a million residents either.

But each of the Hawaiian islands is a county in the state and state leaders know the islands will have to work together in order to meet the overarching goal. For example, it would be possible for islands like the Big Island to get all of its power from renewable sources, but nearly impossible for an island like Oahu, which continues to burn oil for electricity. Changes in the state’s energy infrastructure will have to take place in order to make all of the islands sustainable.

Oahu is embarking a major demonstration project using deep ocean water and heat exchangers to cool a block of buildings. The pilot project is modeled after technology currently being used at the Natural Energy Lab.

The state is also developing plans to connect the various islands’ independent energy grids so that renewable energy generated on sparsely populated islands can be transmitted to smaller and more densely populated islands like Oahu and Maui. Underwater cables are expected to cost the state about $1 billion.

"But it's one of the things we're probably going to have to do if we're going to wean ourselves down to 30 percent oil," Deveau concluded.