Off-the-Grid Heat: Alternative Fuel Sources

If you live in the country, own a cabin in a remote location or simply want to reduce your energy costs, you may wonder what type of heating system is best for your situation.

Whether you want to stick with a traditional fuel or opt for innovative new technology, you have a variety of choices for heating, cooling and providing power to your home. Some you may recognize; others may be unfamiliar. Which source is right for you depends on how much you’re willing to invest in technology, how much you’re willing to spend in yearly fuel costs and which fuel options are available in your area.

Electricity: almost off the grid
Perhaps the simplest way to heat your home, electricity can power everything from a furnace to a water heater to kitchen appliances. In fact, electric service could be the only utility you’d need to set up in your home. The downside is that electricity remains the most expensive fuel source, and although it can be generated by gas, nuclear, hydroelectric and solar sources, in some regions electric power requires burning millions of tons of coal (which greatly adds to greenhouse gases in the atmosphere). And if an all-electric home loses power during a storm, nothing works until service is restored.

Fossil fuels: the old standbys
Despite advances in technology, fossil fuels are the most common power sources for rural homes. Though their costs continue to rise, if you’re looking for the easiest setup, these fuels are popular options:

  • Propane: Also known as liquefied petroleum gas (LPG or LP-gas), propane can be used to fuel a furnace, cook food and, for true off-the-grid living, power a refrigerator. It’s relatively affordable – about half the cost of electricity – and propane-fueled appliances are usually more efficient than similar electric units. But propane-powered appliances are typically 20 percent to 30 percent more expensive than their electric counterparts, and you’ll need to pay a propane company to either regularly fill a stationary tank or swap an empty portable unit for a full one.
  • Heating oil: Also known as No. 2 fuel oil, this liquid petroleum product is the most economical fossil fuel. It creates an even, comfortable heat, and because it has to be vaporized before it can combust, it’s a safer fuel source than pressurized propane. The main downside is the mess. Fuel oil is similar to diesel fuel, can leave sooty deposits as it burns and at times have a rather distinctive odor. In addition, it’s not available in all parts of the country, and strict environmental regulations govern how homeowners can store it.

Heat transfer: harvesting free heat
Generally speaking, heat transfer is the process of extracting heat from one location and moving it to another. Though the equipment can be expensive, the heat it generates is virtually free – all you pay for is the electricity to drive the system.

To use heat transfer, you’ll need either an air-source heat pump or a geothermal system. Air-source heat pumps operate similarly to a Freon-driven air conditioner. During the summer, the heat pump removes heat from inside a home and transfers it outdoors through a condensing unit, cooling the house. During the winter, the process is reversed – heat is captured from outdoor air, compressed and released inside. But because colder air has significantly less heat to harvest, an air-source unit typically shuts down once the outside temperature reaches 20 degrees, meaning the system isn’t well-suited for very cold climates.

An air-source heat pump removes warm air from your home during the summer and harvests it from the outside during the winter.

Geothermal systems, on the other hand, capture heat from the ground by pumping water through an underground piping loop. The water absorbs heat from the soil and then delivers it to the home, where it’s warmed from about 55 degrees to about 70 degrees by an auxiliary heater. The water is then circulated throughout the house either through a grid of tubing installed in the subfloor (referred to as radiant floor heating) or via room radiators.

The drawbacks to most geothermal units is that you must have a substantial area of land (at least one-quarter acre) for the underground piping and be willing to invest money in the installation. And of course you’ll still need to supply fuel – electricity, propane or fuel oil – to power the auxiliary heater.

A geothermal system requires substantial underground tubing, installed either horizontally in a grid as shown here or vertically down a deep shaft, for the water to absorb enough heat.

Solar energy: free, clean and abundant
An inexhaustible source of free energy, solar power encompasses two distinct categories: electricity-producing photovoltaics and solar space heating. Originally developed to power satellites in the 1960s, photovoltaics (PV for short) directly convert solar energy into electricity that can power either electric baseboard heaters or a blower motor in a conventional furnace that uses fuel oil, propane or gas. (For more information on photovoltaics, see “Solar Sunrise,” March/April 2002, p. 46.) Solar space heating, on the other hand, uses the sun’s energy to heat water that’s been fed through a series of roof-mounted panels, after which it’s pumped through a radiant floor system or room radiators.

If you live in a very sunny climate, photovoltaics can generate enough electricity to heat and power your home.

If you want to live completely off the grid, solar energy can both power and heat your home. But the systems are very expensive and require a lot of daily sunshine to effectively operate. (On cloudy days, traditional electric service kicks in if the photovoltaics aren’t producing enough electricity.)

Biomass fuels: feel the burn
The oldest fuel source known to man, biomass fuels are plant matter that can be burned to provide heat. The three most common forms of biomass fuels for the home are wood, processed cellulose pellets and corn. If you have easy access to firewood, a wood stove can heat a house for pocket change. Basic wood-burning stoves are much cheaper than other heating systems, and they don’t contribute to the greenhouse gases associated with fossil fuels (though they do release particulate matter into the atmosphere).

Similarly, pellets and corn can be burned like wood and are quite economical. Pellets cost about $200 a ton; corn usually averages about $75 a ton (roughly 36 bushels). Considering it takes about 2-1/2 to 3 tons of fuel to heat a 2,500-sq.-ft. home for one season, the cost savings from these alternative fuels can be quite substantial.

The main downside to using biomass fuels is labor. Firewood has to be cut (unless you simply have it delivered), and the burners must be regularly stocked with fuel. And because all three sources require a blower motor to move the heat out of the stove and throughout the house, you’ll still use some electricity.

Given the host of available options, choosing a heating system requires investigation and careful consideration of a variety of factors. When making your decision, determine how much you’re willing to spend on equipment, learn about financial incentives available from local utility companies, and think about how much work you want to put into maintaining a system. Also analyze installation costs and how much money each system could save you. Once you’ve looked at all the facts, you’ll be able to select the option that best suits your priorities.

Moving the Fire Outside
Outdoor furnaces are growing in popularity not only because they move the mess and hazards of a fire outside but also because one unit can heat your house as well as your shop (and a hot tub or swimming pool to boot).

An outdoor furnace, which resembles a sheet-metal garden shed with a chimney, is a wood-, corn- or pellet-fueled boiler that heats water and pumps it into your home, where it’s distributed through a radiant floor system, individual room radiators or a heat exchanger in the plenum of an existing forced-air furnace. The entire system is digitally controlled, and an indoor thermostat fires the furnace – when more heat is needed, the thermostat sends a signal to produce additional combustion air. Expect to pay between $4,500 and $7,500 for most units.