Propane Furnaces vs. Ground Source Heat Pumps
PERC (Propane Education and Research Council) recently put out an excellent comparison between high efficiency propane furnaces and ground source heat pumps (GSHPs). Every consumer has their different preferences (comfort), concerns (upfront costs and annual heating costs), and constraints (price), so PERC broke down the differences to give them the most data available.
Beyond the above factors, two of the most important in choosing your system are design and location. A ground source heat pump transfers heat between your house and the ground or a nearby water source (which retain heat more than the surrounding air).
The system can work in reverse automatically, so it can either draw heat in on a cold day to heat your house, or suck the heat out to cool your house on a hot day. One key drawback to a GSHP is that is requires site-specific designs (both inside your house and out to reach the ground or water source), and this will add to the overall costs. On the other hand, propane powered furnaces are straightforward in design and installation, and the turnkey nature can translate into lower costs. HVAC contractors will also generally understand the more simplified setup of a propane furnace versus the specific challenges for installing a heat pump.
Propane furnaces come in all shapes and sizes and have a typical operating life of 15 to 20 years. Many propane furnaces with an AFUE of 95 or higher qualify for tax credits and other incentives that can pay a portion of your purchase and installation costs.
One other potential option is a dual-fuel heat pump, where a propane powered furnace acts as a back-up to the air or ground source heat pump. This will translate into energy source flexibility and on average a faster payback than for a stand-alone GSHP. This is also good for colder climates where heat pumps can become less efficient at lower temperatures.