Rising heating oil prices and dire forecasts predicting the most expensive heating season ever have left many local homeowners feeling anything but warm and fuzzy, with some scrambling to find cheaper ways to heat.

The good news is that there are options to heating with oil or natural gas, which tends to rise in price as oil does. Most of the alternatives require a hefty up-front investment, though.

But first, to the grim math facing homeowners as winter approaches:

The average cost of home heating oil in Massachusetts this past week was $3.91 a gallon, according to the state Department of Energy Resources survey. That's up 26 percent from the same week last year and up 44 percent from the previous year.

Put another way, filling a 275-gallon oil tank at the current average price costs a whopping $1,078, a budget-busting $220 increase from this time last year.

The U.S. Energy Information Agency predicted in a report released early this month that this winter will be the most expensive heating season on record for people who heat with oil or propane.

Richard and Mary Clark of Rutland no longer have to fret about that, though.

They had their old propane heating system ripped out in October in favor of a geothermal system that taps into the natural heat of the Earth underground.

“We had thought about solar or some form of heat like that to reduce our costs overall, and we've been thinking about it for some time, going back and forth with it,” Mr. Clark said. “We thought something like this would work, and it has.”

Mr. Clark said he set his thermostat at 68 degrees after the new system was installed last month and his house has remained within a degree of that temperature ever since. While the system will add to his electric bill to run a sophisticated heat pump, he will never have to buy a drop of oil, propane or natural gas for heating as long as he lives in the house.

Even in the most frigid of winters, the temperature below about eight feet underground holds steady at 51 degrees. Fluid running through a closed loop of pipes snaking deep into the ground soak up that heat and bring it to the surface, where it is extracted and concentrated by a geothermal heat pump, explained Chris Marengo, owner of Off the Grid CS Inc. in Leicester, which designed and installed the Clarks' system.

The system works in the reverse, carrying heat from the house down into the ground, in the summertime.

“The typical person who burns $3,000 a year in oil will pay about $440 a year to heat and cool their home with geothermal,” Mr. Marengo said.

There's just one catch, and it's a big one: the cost of retrofitting a house for geothermal heating and cooling can cost tens of thousands of dollars, Mr. Marengo said.

Mr. Clark said the investment made financial sense for him because he has owned his house for two decades and has no intention of ever moving.

“It's expensive, but overall, we've estimated that we'll recover the cost in five or six years,” he said.

Maryann Wood of Holden had a geothermal system installed at her house several years ago. While the system isn't large enough to completely supplant her old furnace in the dead of winter, her annual oil consumption has dropped from about 1,100 gallons to less than 400 gallons, she said.

Taking into account energy efficiency tax credits, she expected to recoup the cost of the geothermal system in seven years.

“We're ahead of schedule and really pleased,” she said. “I couldn't see the price of oil ever coming down for long, so I started looking at what else we could do.”

Mr. Marengo said some of his customers, for whom a geothermal retrofit is out of financial reach, have instead installed solar panels designed, not to generate electricity, but to heat up air in a network of small ducts. The heated air is then circulated into the house by a motorized blower.

The system doesn't work when the sun isn't shining, of course, but it can help minimize the amount of oil a homeowner has to buy at nearly $4 a gallon and climbing. Such systems start at several thousand dollars, he said.

Industry statistics indicate a rising number of homeowners also are trying to cut down on the amount of heating oil they use by installing wood or pellet stoves, which can stand alone or be inserted into traditional fireplaces.

From April to June this year, shipments from manufacturers to retailers of wood stove inserts, pellet stoves and pellet stove inserts shot up 32 percent, 59 percent and 72 percent, respectively, according to the Hearth, Patio and Barbecue Association.

“This year has been a busy year,” confirmed Ron Higgins, president of Higgins Energy Alternatives in Barre. “People are certainly concerned about the increased cost of fuel oil, so we're seeing a spike of people coming in to see what they could do to save some money on heating.”

Wood and pellet stoves are designed to capture and circulate much more of the heat from a fire than logs burning in a traditional fireplace, a case in which most of the heat is lost up the chimney. The cost of wood and pellet stoves range from about $2,000 to $4,000, not including installation, which typically runs another few thousand dollars depending on the situation, Mr. Higgins said.

For a pellet stove, the most efficient of the hearth products, an average user burns about a bag of wood pellets a day. That works out to around three tons, or roughly $750, a year, he said.

“So for less than one tank of oil, you can be toasty warm all winter with a pellet stove. The savings can be significant,” Mr. Higgins said.

For those with wood stoves or traditional fireplaces, new compressed saw dust bricks and logs on the market burn longer, cleaner and are more energy dense than cord wood.

Steven Lanata, one of the owners of BioPellet LLC in Connecticut, said his company has sold out of BioBricks compressed sawdust blocks through February and into March.

“It's insane. I get calls all day with dealers screaming at me. ‘Where's my truckload?' We run our plant seven days a week, and we still can't keep up this year,” Mr. Lanata said.

The bricks weigh about two pounds each and are made of kiln-dried sawdust with no glues or chemical binders. The average burn time is an hour a brick, Mr. Lanata said.

Similar products in the form of artificial logs also have been selling well here, Mr. Higgins said.

One other heating alternative, one originally intended to compete with oil on environmental grounds, may soon cost less too.

People have long been converting used cooking oil from restaurants into biodiesel fuel for trucks and other diesel vehicles, but the converted cooking oil also will burn in oil furnaces without any modification of the equipment, noted Sarah Assefa and Scott Guzman of the Empower Energy Coop in Worcester.

The coop has been making and selling biodiesel in the city on a small scale for years. The eco-friendly product currently sells for $4 a gallon, but Empower has no plans to raise the price in the foreseeable future, while the price of fuel oil is expected to continue to rise this winter.

The self-described social entrepreneurs collect used cooking oil from more than two-dozen restaurants around the city, pumping it into barrels which they load onto a pickup truck for transport.

“Then we filter it and process it,” Mr. Guzman said. “Processing includes drying it out to remove any water. We mix it and heat it with two chemicals, potassium hydroxide and methanol. Those are both things found in nature that can be made from wood.”

Empower Energy has the capacity to make about 400 gallons of biodiesel a month now, but Ms. Assefa said the coop is working to increase its capacity over the next year.

While some oil companies now add small amounts of biodiesel to petroleum-based fuel oil to reduce pollution, it might one day be possible for people to heat their homes with oil burners using only biodiesel – and to save money while doing it.