UNITY, Maine — Eighty-six percent of houses in Maine do not meet minimum housing efficiency standards, a state energy official told about 50 people gathered for a discussion of solar thermal energy at the Unity Community Center on Monday evening.

“Maine has the oldest housing stock in the nation, and the highest dependency on foreign oil. A lot of the houses are not insulated, and most are underinsulated,” Richard Fortier, commercial energy auditor and program manager for Efficiency Maine’s solar rebate program, told the group. He was citing a recent energy efficiency survey of homes in Maine.

“This state is in a lot of trouble, energywise,” Fortier said.

Efficiency Maine is a program intended to address the issue of energy efficiency in Maine homes by promoting the more efficient use of electricity, helping Maine residents and businesses reduce energy costs and improving Maine’s environment, according to the program’s Web site. It is funded by electricity consumers and ad-ministered by the Maine Public Utilities Commission.

For more than two hours Monday night Fortier and Bob Hussey, president of Solar Tech Inc. in Waterville, gave details and answered questions on the use of solar thermal energy for hot water, solar air for heating and solar photovoltaic as a power source.

A few in the audience already had installed their systems and had come looking for refinements.

“This was a savvy audience,” Hussey said after the meeting, “more savvy than most.”

Fortier said Efficiency Maine is going to look at energy efficiency for fossil fuels — gas, propane and oil — and electricity and develop programs to help commercial and industrial users to help them reduce costs.

The Maine State Housing Authority takes care of low-cost housing energy needs to make homes more efficient, he said.

“Maine State Housing has dealt with everybody of low income, and left everyone else to their own devices,” Fortier said. “We’ll be working on programs that will help weatherize homes for people in the middle and upper income stratas.”

Efficiency Maine also plans to train business leaders how to operate efficiently, he said of the proposed two-pronged attempt to reduce energy costs in a community.

“Everybody wants wind [power] or geothermal,” Fortier said. “Geothermal, solar and wind power solutions have been around for many years, but they present many snags unless someone really understands the industry.”

He said solar energy is the most cost-effective energy for the investment.

Hussey talked about the ratings and sizes of solar panels and urged people to have an energy audit to understand the payback period of an investment.

“The larger the panel you have, the less cost per panel for energy,” he said.

Hussey explained that there are two kinds of panels: the evacuated tube panel, which is more effective but twice as expensive as the other kind, the more common flat-plate panel that usually rests on a roof.

Urging people to shop around for the best and most effective panels and contractors, he referred the audience to a solar rating and certification organization at www.solar-rating.org.

Hussey recommended looking at two other Web sites for information and ideas: www.homepower.com, Home Power Magazine, and www.motherjones.com, Mother Jones Magazine, for tips on solar energy construction.

Tess Woods, executive director of Unity Barnraisers, also provided background information on the community’s concerns for efficient fuel use. The group began “Neighbor Warming Neighbor” last fall, in which more than 60 volunteers weatherized 34 homes and provided weatherization materials for another 32 homes, Woods said.

George Chappell may be reached at 236-4598 or at gchap@gwi.net.