Coal and wood are gaining popularity as home heating alternatives to increasingly costly natural gas and oil.
Some Massachusetts companies that sell coal and wood as well stoves report sales have more than doubled in recent months compared with a year ago.
"People are shocked by their oil prices," said John Sullivan, owner of Energy Unlimited of New England, a Wayland business that sells wood stoves and bags of sawdust-based pellets.
Mike Tavalone, manager of a Vermont Castings Factory Store in Natick, said demand for wood pellet stoves is so high that his store won't have any stoves in stock until the middle of January.
At Williams Coal & Oil in Braintree, president Brian Williams said he's recently heard from dozens of people who are using coal stoves that they bought during the energy crises of the 1970s and then mothballed.
While coal and wood are sometimes considered energy sources of the past, they're enjoying a resurgence because natural gas costs are projected to rise by about 50 percent compared with last winter, with heating oil expected to grow 30 percent, the AP reports.