PETERSHAM, Mass. -- As home heating costs in Massachusetts increase, outdoor wood furnaces are becoming more and more popular in Petersham.

NewsCenter 5's David Boeri reported Tuesday that an outdoor wood furnace is a wood-fired boiler, which is wrapped with a water tank and placed in a small, insulated shed. The shed has a smoke stack.

The furnace is usually set at a temperature of 180 degrees, and the water is pumped into a home for heat and hot water.

"It's as warm as you want it. It's almost an inexhaustible supply of heat," outdoor wood furnace owner Jeff Pooser said.

"It's dynamite. I am burning all of the wood on my property. I go out there about once a day," outdoor wood furnace owner Ari Pugliese said.

One local storeowner said that the outdoor wood furnaces could save homeowners money on their home heating bills. Elliot Starbard said he's sold hundreds of outdoor wood furnaces.

But, not everyone is happy with the smoke that comes out of the furnace. One homeowner's furnace had to be moved because officials said that the smoke was visible, which was a violation in the town's historic district.

So far, the state has no regulations about outdoor wood furnaces, but some say the furnaces are better for the environment than some other home heating sources.

According to officials in Connecticut, the emission from one oil furnace is equivalent to the emissions from 39 gas furnaces, but the emission from one outdoor wood furnace is equivalent to the emissions from 3,000 to 8,000 gas furnaces.