The Cost Analysis Module is used to estimate the system cost. Two major types of costs are considered, initial investment and maintenance costs. The general structure of this module is based on the use of unitary tabulated costs both for labour and materials. The knowledge about unitary costs and case study conditions (given by the user in the energy analysis module) are enough to provide an estimation of the total project costs.
Initial investment cost includes the following cost categories:
Feasibility analysis; typically includes such items as site investigations, soil/hydrology assessment, environmental assessment, a preliminary system design, including loop sizing and layout, detailed cost estimate, and a final report. This is particularly important for projects larger than 100 kW.
Development; includes costs for contract negotiations, permits and approvals, project financing, development phase project management and any development related travel costs.
Engineering; includes costs for the GSHP system design, tenders and contracting, and construction supervision.
Renewable energy equipment; as defined here, includes, when applicable, the system’s ventilators, drilling, trenching, pipes, valves, fittings, electrical equipment, controls civil engineering and transportation costs.
Contingencies; the allowance for contingency items should be based on the level of accuracy associated with the pre-feasibility estimate of the project costs. Typically, a pre-feasibility level cost analysis should be accurate within 40 % to 50 %. However, this accuracy will depend on the expertise of the study team, the scale of the project being considered, the level of effort put forward to complete the pre-feasibility study and the availability of accurate information. It is certainly possible that experienced users could estimate costs in the range of 10 % to 20 % of the total initial project costs (excluding contingency costs).
Periodic cost represents recurrent costs that must be incurred at regular intervals to maintain the project in working condition. ETVS may require yearly inspection and
cleaning procedures and as there are not major moving parts only the ventilator may require to be replaced e. g., every 10 years.
The output of the Cost Analysis Module is the required investment cost and annual maintenance costs for a system as defined in the Energy Analysis Module. These represent the negative project cash-flows that should be balanced by the positive ones estimated in the two previous modules. The analysis of their combined effect along the project life is made by the Financial Analysis Module.