Identify the ground-source system being purchased
An owner replacing HVAC in business premises may compare a conventional system with a geothermal proposal that includes a projected investment credit. The geothermal label is not enough to establish the tax result. Identify the equipment, its function, ownership, construction dates, and the cost components before relying on the projected benefit.
The IRS Form 3468 instructions describe geothermal heat pump systems as equipment using the ground or groundwater as a thermal source for heating a structure or a thermal sink for cooling it. The instructions address these systems within the section 48 energy credit framework. A general air-source heat pump or an efficient conventional HVAC replacement does not qualify under that description merely because it saves energy.
Ask the designer and installer to identify the ground loop or groundwater components, heat pump equipment, controls, distribution components, and related construction. Give that schedule to the tax adviser to determine which items belong in the applicable credit basis. The contractor’s total building-renovation quote should not be treated as a single qualifying asset without review.
Compare the complete cash investment and supported credit
Consider a hypothetical $360,000 geothermal HVAC project for occupied premises. The detailed quote includes $190,000 of ground-source equipment and installation, $80,000 of ground-loop work, $55,000 of ordinary building alterations, and $35,000 of other work. Assume the adviser supports $280,000 as the qualifying investment after reviewing the actual scope.
At a purely illustrative applicable percentage of 30%, the tentative credit would be $84,000. Using the full $360,000 quote instead would produce $108,000, a $24,000 difference. These figures do not establish actual component eligibility or the credit percentage for any project. They demonstrate why the equipment boundary matters before the owner compares bids.
Suppose a conventional alternative costs $220,000. The geothermal proposal’s gross additional cash cost is $140,000, and subtracting the assumed $84,000 credit yields a $56,000 difference before timing, tax basis effects, depreciation, financing, maintenance, and operating savings. Do not present that simple comparison as a complete payback calculation. The owner still needs to fund the gross project and verify when any tax benefit can actually be used.
Establish the applicable conditions and construction evidence
Have the adviser identify the relevant credit rules for the project’s construction and placed-in-service dates. The section 48 framework includes timing, increased-rate, and other conditions; the applicable result should follow current law and the specific technology. Avoid importing the timing rules or termination dates of a different energy credit into the geothermal estimate.
If an increased amount depends on prevailing wage and apprenticeship requirements or an exception, establish the supported path before signing the construction contract. Provide the contractor with the required recordkeeping and correction process as appropriate. A promise to provide paperwork after completion is less useful when worker and subcontractor records were never retained.
The project also needs a supported cost allocation and evidence that the equipment is ready and available for its intended business use. Keep commissioning results, installation approvals, operational testing, invoices, and any separately required permits. Payment in advance does not alone establish that the system has been placed in service. Ground work and equipment installation can occur on different dates, so document the complete functional assembly.
Keep the premises and tax records aligned after installation
Retain design specifications, component costs, ownership contracts, construction dates, wage or exception support, commissioning evidence, credit calculations, and filed forms. Reconcile the capital asset register with the credit basis and any required basis adjustment. The building’s financial accounting category does not automatically determine the federal credit population.
Maintain the equipment under the actual engineering and environmental requirements, including any groundwater or drilling approvals that apply. The tax analysis does not establish permission to construct or operate the system. Record modifications, replacement components, disposal, and changes in business use so the adviser can review depreciation and any credit consequence.
This guide does not determine that a proposed system qualifies, calculate a final credit, or predict savings from a specific building. Current law, taxpayer status, construction timing, labor conditions, financing, basis, and recapture rules require individual review. Its practical owner decision is to compare geothermal HVAC using a verified equipment boundary and a complete funding model, while preserving the records needed to support the actual credit claimed for the operating premises.
Sources & further reading
Consult the original guidance and its effective dates. These references support the educational discussion; their application depends on the specific facts.