Energy prices are due to rise at least 7 percent in the winter months, even while Massachusetts remains the most energy-efficient state in the country for the seventh year in a row.

At a recent Walpole Chamber of Commerce event at Dean College in Franklin, Massachusetts Congressman Joe Kennedy III spoke bluntly about how energy prices will see a spike this winter.

“There was a price increase that took place this summer,” he said. “You haven’t heard about it because it’s summer. We’ve haven’t had a huge increase in energy. But come this winter, if it’s a cold one, you’re going to see energy prices spike well into double-digit rates.”

Spokesman for Eversource energy, Michael Durand, said consumers can expect “a modest increase in natural gas prices.”

Durand said that on average the increase will result in about $11 more in bills each month. This would bring the average bill from $153 to $164, he said.

Durand mentioned that hikes like this are not typical, and could be due to a few factors.

Eversource purchases its gas from pipeline companies and sells it to Massachusetts consumers, sans profit, said Durant. This means that whatever the supplier charges, in this case Marcellus Shale in Pennsylvania, Eversource passes onto its consumers.

Marcellus has been the source of low gas prices in the region, taking advantage of a combination of new technology and relatively recently discovered natural gas reserves in Pennsylvania and West Virginia.

One factor in rising prices, said Kennedy, is the way that grid operators have adjusted the way energy auctions take place. Another reason, said Massachusetts Department of Energy Resources Commissioner, Judith Judson, is because of the rough hurricane season.

“(Massachusetts) has definitely been impacted by the severe weather in the Gulf area of the country,” she said. “It drives up the underlying cost of fuel in the energy market.”

Recognizing the inevitable 7 percent increase, Judson said there are ways that residents can mitigate those costs through the Mass Save program. Through Mass Save, consumers are eligible for a free energy-efficiency consultation. The state-run program offers rebates for better home insulation, as well as free digital thermostats and light bulbs that reduce consumption by about 60 percent.

“Our utilities have the most aggressive, nation-leading energy efficiency programs that run under the Mass Save brand,” said Judson. “They deliver billions of dollars to Massachusetts consumers each year.”

She said that particularly this winter, Massachusetts residents should take advantage of the Mass Save program.

“They’re a great way for residents and businesses to save money on their energy bills to counter any price increase that may occur in the energy market, and while doing so to also lower emissions in the commonwealth,” she said.

The final factor contributing to the energy spike is a lack of pipelines though the Northeast region.

Judson said that instead of planting more pipelines, she’d prefer to see an increase in solar, wind and hydro energy. The more green-work Massachusetts does, the lower energy will be for everyone, she said, explaining the plan to replace all streetlights with LED bulbs.

“We reduce the electric consumption across the commonwealth, and therefore lower the price that we are paying for electricity and heating,” she said.

Scott Calzolaio can be reached at 508-734-0389, or by email at scalzolaio@wickedlocal.com.