Estimate the nominal geothermal heat pump capacity needed from a building design load, desired load coverage, sizing allowance, and available unit size. The calculator rounds the target into whole equipment units and identifies nominal installed capacity and any uncovered design load. It also gives a preliminary borehole count from an entered design extraction rate.
Target capacity is a planning value, while nominal installed capacity reflects whole selected units. Final selection must use manufacturer performance at the actual design temperatures and distribution conditions.
Oversizing can increase cost and cycling; undersizing can increase backup-energy use. Final sizing requires a code-compliant load calculation and equipment selection data. Borehole design requires site-specific thermal properties and long-term simulation.
A 36 kW design load at 100% coverage plus a 5% allowance requires 37.80 kW. Using 12 kW units requires 4 whole units.
No. Use a recognized building load calculation and site-specific equipment performance data for final design.
Bivalent systems may intentionally use backup heat during the coldest design conditions.
It adds a selected margin after applying the target load-coverage percentage.
The calculator rounds up because partial equipment units cannot be installed.
No. Borehole yield requires site-specific geology and thermal design.
| Variable | Use |
|---|---|
| Design load | Building demand at design conditions |
| Coverage | Share assigned to heat pumps |
| Allowance | Explicit additional sizing margin |
| Unit size | Delivered capacity basis for unit count |