Feasibility study for a geothermal heat pump application for a house + greenhouse

Client: Private owner
Location: Crespellano (Bologna), Italy
Date: 2013

The study is aimed to improve the energy efficiency of a rural building consisting of 3 housing units (80 m² each) and a heated greenhouse (40 m²) for aromatic herbs-growing during the winter season.ortofoto_bing

Project Goals

  • Technical economic feasibility study of non conventional geoexchange system for house and green house heating using a geothermal heat pump

Innovative aspects

Heating system for rural building (20°C) with heat recovery for greenhouse heating (5°C).

Activities Performed

  1. Analysis of the existing heating system and of thermal energy demand for heating and hot water;
  2. Estimation of aromatic herbs-growing greenhouse heat demand;
  3. Preliminary design of two geoexchange system (borehole heat exchanger, horizontal collector) for three different scenarios:
    • greenhouse + 1 apartment;
    • greenhouse + 2 apartments;
    • greenhouse + 3 apartments.
  4. Technical-economic feasibility study and estimation of the return period for the different solutions and scenarios.

Technical data

Operating mode: heating
Thermal power at the evaporator: 6 kW
Thermal power at the condenser: 8 kW
Fluid flow rate: 1 m³/h
Geoexchange system inlet temperature: 1°C
Geoexchange system outlet temperature: 6°C


Geoexchange system with borehole heat exchangers (BHE)Picture2planimetria_SGV

Geoexchange system with horizontal collectors


Technical Feasibility


Economic feasibility

The feasibility study led to the design of a non conventional heating system using ground source heat pump, and to the identification of the best solution from a technical and economic point of view.
The use of in-house developed software allowed for a proper geoexchange system design.
The analysis of different technological solutions and different scenarios provided detailed information about projects with different investment costs and return period.

Economic Feasibility

The two solutions have been compared to a revamp of the existing heating system (natural gas boiler) and the realization of a radiant heating system for the greenhouse.