How Propane Enhances Alternative Heating Systems

Homeowners spurred by federal tax credits and other incentives to reduce their energy use and related expenses are increasingly turning to alternative heating options. Systems including geothermal (or ground-source) heat pumps for space heating and solar thermal collectors for domestic water heating are among the more popular types of alternative systems.

Propane can assist alternative heating systems by increasing their reliability and performance, satisfying homeowners' desire for comfort and convenience as well as for environmental friendliness. Incorporating a propane-fueled backup into an alternative heating setup creates a hybrid heating system that optimizes the energy-saving benefits of alternative heating.

For instance, ground-source heat pumps (GSHPs), which leverage the relatively stable temperature of the earth or a body of water to provide cost- and energy-efficient space heating and cooling, are typically designed to provide only 75 percent to 80 percent of a home's heating needs.

A supplemental propane heating system, such as a high-efficiency furnace or boiler, can make up the difference and also provide backup. The propane-fueled equipment operates only when necessary or called upon by extreme load conditions, such as in late winter when ground temperatures are at their lowest.

A high-efficiency propane furnace can also serve a similar role for more conventional air-source heat pump (ASHP) systems. Best of all, the furnace allows contractors to "right-size" ASHP equipment for that role, significantly reducing its cost to purchase, install, and operate.

The same logic holds true for propane-fueled backup systems designed to supplement solar thermal collectors for water and/or radiant space heating. Solar thermal collectors have come a long way in their efficiency and payback potential, but they still depend on the sun's heat — in steady doses — to meet homeowner needs and expectations for convenience and comfort.

A typical hybrid setup for solar thermal is similar to the heat-pump example. In this case, however, a propane water heater — ideally a space- and energy-saving tankless unit or two — provides supplemental and backup water heating for the house when called upon.

In this scenario, roof- or ground-mounted solar collectors are plumbed to a large-capacity storage tank. As the collectors heat and deliver water into the storage tank, that water is made available for distribution to a radiant space heating system or to the various appliances and fixtures that use hot water.

When the solar collectors can't keep up with demand, such as during a consistently cloudy period, a short winter day, or during periods of higher than normal hot water usage, the on-demand propane tankless water heater kicks in to make up the difference. The result is a more reliable and steady delivery of hot water.

Like the GSHP setup, the supplemental use of propane for solar water heating systems significantly reduces the energy cost and carbon footprint when compared to supplementing with electricity as the backup source. Also, right-sizing solar panels to incorporate a propane tankless water heater for supplemental water heating saves on the overall cost of installation.

Even better, all of these systems — the primary ASHP or GSHP, the solar thermal systems, and the supplemental propane equipment — qualify for federal energy tax credits (and perhaps state and local rebates and other incentives) to help offset their upfront costs and hasten their return on investment.

To learn more about propane-related tax credits and other incentives on energy-efficient propane heating equipment and tankless water heaters, enroll in one of our free training programs.

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How Propane Enhances Alternative Heating Systems


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