What it costs: Heat pumps | Features

Specification options: Ground-source heat pumps
	Capital cost	Lifecycle cost	Expected service life
Domestic scale: 4–8kW heat output
Horizontal pipework laid in trenches	650–1,050	1,180	50–100
Horizontal looped (slinky) pipework laid flat in trenches	730–1,130	1,360	50–100
Vertical pipework in boreholes	700–950	1,300	50–100
Heat pump 4–8kW heat output	800–1,000	2,190	15–25
Commercial scale: 30–50kW heat output
Horizontal pipework laid in trenches	625–1,025	1,080	50–100
Horizontal looped (slinky) pipework laid flat in trenches	700–1,100	1,240	50–100
Vertical pipework in boreholes	1,080–1,480	1,710	50–100
Heat pump 30–50kW heat output	650–800	1,790	15–25
Table notes A discount rate of 3% is used to calculate values. Lifecycle costs are indicative and are based on the average of capital costs and service lives. Lifecycle cost for pipework allows for a probability of pipe failure and costs associated with the circulation pump. Costs in use include inspection, servicing, allowance for responsive maintenance. Distribution side costs and energy costs are excluded. Pipework is a closed loop system of HDPE to relevant British Standards. Heat pump to British Standards noted in text. Pipework costs will vary with nature of soil and heating demand of building. Number and depth of boreholes and degree of grouting will influence cost. Economies of scale may apply to larger developments. A cost analysis based on project specific information is essential for a realistic appraisal.