The payback period varies significantly, as geothermal systems are customized to individual homes. Factors that influence the payback period include:
In addition, premium system options may be selected for comfort reasons (i.e. combination distribution systems, ECM fans motors, etc.) which increase the total cost of the geothermal relative to a conventional heating system.
A simple payback analysis can be calculated from estimates/data provided by a geothermal contractor. To calculate payback, you will need:
Simple payback formula: Payback in years = (A – B) / C
Use the Geothermal heat pump energy costs and savings worksheet to calculate your estimated payback on a geothermal system.
A vertical or open loop configuration is best for a smaller lot. Have a contractor assess your home to confirm whether you can install a geothermal heat pump based on:
Air-source heat pumps absorb heat from outdoor air in winter and release heat outdoors during summer. The extreme outside air temperatures in Manitoba limit the effectiveness of air-source units in the coldest months of the year. In contrast, geothermal heat pumps extract heat from the ground, and provide a stable source of heat in the winter months.
Efficiency is measured by the seasonal coefficient of performance (SCOP). This is determined by dividing the energy output of the heat pump by the electrical energy needed to run the heat pump system over an entire heating season. The higher the
SCOP, the more efficient the heat pump is. Seasonal
COPs of 2.0 to 3.0 are typical for today's geothermal heat pumps. This means that for every unit of electricity that is used to operate the heat pump, two to three units of heat are generated. The efficiency for a heat pump — 200 to 300 per cent — can be compared with a furnace's
COP:
Yes. Geothermal heat pump manufacturers offer units that produce hot and chilled water, rather than hot and cold air. These units can be connected to hot water space heating (also known as hydronic heating) equipment. The limitation in the heating mode is temperature. Conventional hot water radiators and baseboard-type elements are designed to operate at temperatures of 71 C and above (older systems operate as high as 93 C). Geothermal heat pumps are limited to producing supply water temperatures of less than 54 C.
As a result, on a retrofit basis, a home with existing hot water radiators or baseboards would have to replace the entire heating system, making the economics less favorable.
The best scenario to adapt an existing hot water system to geothermal is if you are currently using radiant in-floor heating or low temperature (less than 49 C) hydronic heating. These systems can operate with the lower water temperature produced by a geothermal heat pump.
With current North American residential design practice, complete space cooling cannot be accomplished with an in-floor system since condensation would occur on the floors' surface. As a result, this system generally must be coupled with an air distribution system (air handler with cooling coil and ductwork) to provide cooling.
The pipe used in geothermal heat pump systems is a high-density polyethylene plastic that has no environmental impact on the surrounding earth. To avoid accidentally cutting the loop, your contractor should supply you with a dimensioned site plan. Always remember to “call before you dig”.
Yes. The amount needed depends on the type of loop system installed. Horizontal loop configurations require the most landscaping work, as a large area of the land surface is disturbed during the trenching process. The amount of landscaping for a vertical loop installation depends on the number of boreholes drilled. See installation photos (open new window).
The purpose of the ground loop is to allow the heat transfer fluid to extract enough heat from the ground for efficient operation of the heat pump. A ground loop is designed to ensure that the heat transfer fluid will achieve a minimum entering fluid temperature when it enters the heat pump unit. Soil type and loop configuration determine the amount of ground loop required to ensure there is enough heat transfer to achieve this minimum entering fluid temperature for the system.
