BELFAST — It’s a high-tech version of juggling. That’s what islands are doing to become increasingly self-sufficient and free of fossil fuels.

Alcatraz, the infamous island prison off San Francisco, now a national monument; the Isle of Eigg off the west coast of Scotland; and Roque Island, a private family owned island off Jonesport: each have developed and are improving ways of blending sources of electricity.

On Oct. 18, speakers at the annual Island Energy Conference (sponsored by the Island Institute, publisher of The Working Waterfront) explained how systems form a micro-grid for the islands, balancing batteries, generators, solar photovoltaic, wind turbines and even tidal power to achieve independence.

ISLE OF EIGG

Speaking to those attending the conference via a computer link-up to the Hutchinson Center, Maggie Fyffe of the Isle of Eigg recounted how homes were lit with gaslights when she first arrived there 38 years ago. The 7,400 acre island, one of the Hebrides near the Isle of Skye, had been a private holding, a throw-back to the Victorian age, participant Mick Womersley noted. Island residents bought it from its wealthy owner in 1997.

When it came time to bring reliable electricity to the island, Fyffe said, a study pointed the way.

“We were convinced renewables were the answer,” she said.

The trust that bought the island raised 1.5 million British pounds to develop the sources, which included a 100-kilowatt hydropower system, two, 10-kilowatt hydropower systems and four, 6-kilowatt wind turbines.

In a ten-year period, the island went from producing an average of 10 kilowatts to 50 kilowatts. The system became fully operational in 2008, Fyffe said, providing island residents with 24-hour electricity. Currently, the island has 53 houses and 22 businesses connected to its electric grid.

Photovoltaic panels have been added more recently, she said.

Though the island has diesel generators for backup power, an average of 85 percent of the electricity on the island has come from renewable sources, Fyffe said. One year, it was 93 percent.

With the recent addition of the sun-powered photovoltaic, she said, it would be possible to reach the 90 percent renewable threshold.

Fyffe said residents have recognized the benefits of living with less electricity using appliances, and also rely on hot water heaters, cook stoves and heating plants using other fuels. Homes have a cap on the use of electricity, so a switch will disconnect the building from the grid if it begins drawing more than 5 kilowatts.

ALCATRAZ

Matt Koenig, a representative of Princeton Power Systems, talked about his company’s work installing converters for self-contained sites like islands that rely on several sources of electricity. The equipment, which the company packages in a shipping container that sits on the site, automatically blends a mix of sources, depending on factors such as demand and time of day.

Alcatraz Island uses the Princeton Power Systems equipment, Koenig said. The island has been off the mainland grid since 1953 when the submarine cable was broken, he said.

The island uses photovoltaic, batteries and diesel generators. Because of its status as a national monument, the photovoltaic panels on the island had to be unobtrusive, and as installed, are less than optimal, Koenig said. Even so, the renewable sources perform well, he said, with the island cutting its diesel consumption from 1,200 gallons a week to 300 gallons.

Princeton Power Systems also has installed its hardware, which create self-contained electric grids, at a U.S. Army base and at a car manufacturer’s headquarters where electric car charging stations are being installed.

ROQUE ISLAND

Anna Demeo of College of the Atlantic talked about a work in progress for Roque Island, a 1,300 acre private, family owned island just east of Jonesport and off Roque Island State Park. There are six houses—three occupied year-round—and a farm on the island where cows, chickens and pigs are raised.

The island now has a submarine cable linking it with the mainland, but Demeo said the 100 family members that make up the trust that owns it want independence.

“We don’t want electrons crossing the water in either direction,” she said, a goal the family is excited about achieving and supportive of her efforts to bring to fruition.

Demeo began designing the project in 2009. One of the goals was use existing equipment.

“We want to do this off the shelf,” she said. First, 4.8 kilowatts of solar panels were installed, and since then, that capacity has been doubled to 10 kilowatts of solar.

Wind power has been discussed, Demeo said, but family members are wary of its aesthetic challenges. Instead, another renewable resource with potential tied to the region, is on the table.

The question, “Could we do some small tidal in some key locations?” is under consideration. As much as 100 kilowatts might be generated, given the higher tides of the region, she said. The Maine Tidal Power Initiative at the University of Maine is providing assistance.

The family supports an approach that would design a small-scale tidal system that would be moored in the water, then seek input from neighbors and local fishermen before pursuing permitting, she said after the conference.

In a paper on the project, Demeo notes that “tidal power differs from solar and wind in that it is a predictable renewable resource.”

For more information about the conference, see: http://www.islandinstitute.org/events/2013-Island-Energy-Conference/15563/