It describes how homes, businesses and industry can spend millions less on power, and others tell success stories.

Maine homes and businesses could trim their overall electricity consumption by 16 percent over the next decade by installing more-efficient lights, equipment and appliances, a new study for Efficiency Maine Trust has concluded.

Programs run by Efficiency Maine Trust can help achieve that goal, depending on how much funding from electricity customers is approved by state utility regulators.

The study was released Wednesday at an awards ceremony and symposium meant to show how, and why, some of Maine’s top employers are investing in energy efficiency. Highlights were presented by a senior staff member of The Cadmus Group, the Waltham, Mass.-based firm that did the study.

Efficiency Maine, an independent agency, was set up three years ago as a trust to guide and administer energy-efficiency and alternative energy programs in Maine. It spent $45 million in its first two years, with the money coming from a small surcharge on electricity bills. That spending leveraged as much as $50 million in private participation.

The programs carried out with the investments are expected to lower electricity bills by $250 million for Maine consumers.

The trust is in the final year of its initial Triennial Plan. The study was done to help develop a second three-year plan and estimate how much more opportunity exists for energy savings.

The plan will need approval from the Maine Public Utilities Commission, which will review it over the next few months.

The study can help the PUC and policymakers quantify potential energy savings, said Michael Stoddard, the trust’s executive director. It also will inform the discussion about what’s the right funding level for Efficiency Maine Trust.

To reach the potential identified by the study, Efficiency Maine will need $175 million, Stoddard said. That’s substantially more than the trust has received from ratepayers, but it reflects the costs and benefits of efficiency versus building new power plants, he said.

“If the policy is to capture the maximum energy efficiency possible in Maine, as long as it’s cheaper than supply, then we’ll need $175 million over three years,” Stoddard said.

By comparison, Maine customers will spend roughly $3.4 billion buying electricity over the next three years, he estimated.

“We don’t have a power plant,” he said. “But we have lots of little projects that are equal to a power plant.”

Electricity rates remain divisive in Maine, blamed by some politicians and business leaders for slowing economic growth. Although Maine’s overall rates are lower than those in most Northeast states, they remain higher than the national average.

But at least for now, rates are going down for residential and small commercial customers in Maine because of the low cost of natural gas used by power plants.

The Maine PUC announced recently that, thanks to falling standard-offer rates for energy, the total bill for both electricity supply and distribution will drop in March by roughly 4 percent for Central Maine Power Co. customers and 3 percent for Bangor Hydro Electric customers. That will trim total costs by $20 million next year, according to the PUC.

The Efficiency Maine study looked at potential opportunities for homes, businesses and industry to save money. The Cadmus Group firm surveyed 103 business and 30 industrial sites to form its projections. The results are considered an estimate, due in part to the complexity of making technical assumptions over time.

The study broke out potential into three categories: technical, economical, and maximum achievable. The economical category covers measures that are deemed cost-effective.

Nearly half of the potential savings could come from homes. If all cost-effective measures could be achieved by 2021, the maximum potential would be roughly 18 percent of forecasted residential electricity sales in 2021.

Top opportunities at home involve lighting, appliances, water heating and consumer electronics. Efficiency measures include fluorescent and LED lights, Energy Star-rated washers, dryers and refrigerators, heat pump water heaters and low-flow faucets, and controlled power strips for TVs and computers.

In the commercial sector, lighting, ventilation and refrigeration lead the potential for savings. Measures include high-efficiency fluorescent and LED lights, demand-controlled ventilation and refrigeration fan controls, and covers for cooler display cases.

For industry, leading opportunities are in machine drives and lighting. Measures include more efficient pump systems and motors, and high-efficiency fluorescent and LED lights.

In the survey, 58 percent of Maine businesses said they consider the payback period when they make efficiency investments. Seven of 10 of those businesses said they want the investment to pay for itself within three years.

The survey also asked business owners and managers about likely participation in Efficiency Maine programs, based on the level of financial incentives. Respondents said they “very likely” would make investments if incentives covered 50 percent to 75 percent of installed equipment costs.

At Wednesday’s symposium, representatives from employers such as Hannaford Bros., Texas Instruments and the city of Lewiston explained how they have carried out energy improvements.

Hannaford looks for payback in less than four years when it makes energy improvements in its supermarkets, said Harrison Horning, the company’s director of energy and facility services.

Texas Instruments bought National Semiconductor and its analog chip-making plant in South Portland last year. The plant competes for investment with plants worldwide, said Andrew McCollough, the facilities engineering manager. So to overcome higher labor costs, the Maine factory must operate efficiently and trim energy use constantly.

On average, the plant has cut its utility bill by $2.5 million over the past eight years. Recently, for instance, it changed out 52 chillers with high-performance versions that cut electricity use by 75 percent. The $1 million investment will pay for itself in three years, McCollough said.

Anh Tuan