This section illustrates the costs of installing a cascaded system of Kensa commercial plant room ground source heat pumps to provide space heating to a medium-sized commercial building with a 75kW peak heat load and 102,500kWh annual space heating demand.
Kensa has calculated this example will require a 500m2 area for the borehole ground array infrastructure.
In this example, a cascaded ground source heat pump system fed by a borehole ground array, could cost in the region of £186,859 and earn £251,183 income from the Non Domestic Renewable Heat Incentive (RHI).
We have provided ground source heat pump installation costs for both self-financed and funded split ownership options versus an LPG boiler alternative.
Example: Finances
Kensa has calculated example costs below to illustrate the upfront finance required and the expected running costs and income generated via the Non-Domestic Renewable Heat Incentive (RHI) over a 20 year period (the duration of the Non Domestic RHI), compared to an LPG system. For a bespoke quote please click here.
Heat Pump System
| System architecture | Cascaded central plant |
| Total heat pump capacity | 75kW |
| Equipment type | 2 x 40kW Plant Rooms |
| Design conditions | 0/50°C |
| Potable DHW temp | Space heating only |
| Integral immersion heaters | No (DNO friendly) |
| Ground array type | Closed loop boreholes |
| Boreholes required* | 1800mtrs |
| Land area required | 500sq/m |
*Boreholes based on average ground conductivity
Total Project Costs, Savings & Returns vs LPG
| | Kensa Ground Source Heat Pumps & Borehole Ground Array | LPG Boiler |
| Finance Option | Self-Financed | Funded Split Ownership | Self-Financed |
| Lifetime Expectancy: Appliance | 20 to 25 years | 20 to 25 years | 12 to 15 years |
| Lifetime Expectancy: Infrastructure | > 100 years | > 100 years | N/A |
| | | |
| Carbon Saved (over 20 years)* | 422 tonnes | 422 tonnes | N/A |
| Local NOx emissions (over 20 years)** | 0kg NOx/y | 0kg NOx/y | 135kg NOx/y |
| | | |
| Appliance & Infrastructure Cost*** | £186,859 | £113,111 | £20,000 |
| | | |
| Running Costs (over 20 years)**** | £130,906 | £130,906 | £184,994 |
| Servicing Costs (over 20 years)***** | £10,218 | £10,218 | £20,436 |
| | | |
| RHI Income (over 20 years)****** | £251,183 | £0 | Not eligible |
| | | |
| Net cost (after 20 years)******* | £76,800 | £254,235 | £225,430 |
*Carbon saving based on carbon emissions of 0.233kgCO2/kWh for electric and 0.241kgCO2/kWh for LPG. Assumes 100% efficiency for electric and 300% efficiency for ground source heat pumps and 85% efficiency for LPG.**NOx emissions based on 56mg/Kwh for gas and liquefied petroleum gas (LPG) boilers ***Costs are for the supply and installation of the Kensa heat pump and ground array only, and the supply and installation of the LPG boiler equipment only. Costs for supply and installation of internals such as radiators, underfloor and heating controls are not included as will be approximately the same for both GSHP and LPG system. ****Based on electric at 15p/kWh and COP of 3. Based on LPG at 40p a litre, energy content of 6.66 kWh/litre and 85% efficiency. Running costs increase by 2.5% per year. *****Ground source heat pumps have no requirement for annual maintenance. However, it is good practice for the heating distribution system to be proactively checked and maintained to ensure optimum performance. ******The non-domestic RHI is a 20 year index linked funding stream which assumes inflation at 3%. *******Net cost for LPG does not include an additional LPG boiler, which will likely need to be factored in during the 20 year comparison period due to the LPG’s 15 year average lifetime expectancy.
Example: Schematic
*For illustrative purposes only
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