SPONSOR CPD PROGRAMME Continuing professional development (CPD) is the regular maintenance, improvement and broadening of your knowledge and skills, to maintain professional competence. It is a requirement of CIBSE and other professional bodies. This Journal CPD programme can be used to meet your CPD requirements. Study the module and answer the questions on the final page. Each successfully completed module is equivalent to 1.5 hours of CPD. Modules are also available at www.cibsejournal.com/cpd Ensuring robust selection and design of surface water source heat pump systems This module explores the main considerations necessary to select and design effective surface water-source heat pump solutions Heat pumps can provide an efficient and low carbon means of using renewable heat from the sea and from rivers, canals and lakes. Although likely to be more expensive to install than conventional technology, they can deliver a cost-effective return on investment, with significant potential benefits from moving to a more renewable solution. There are currently very few UK installations of large-scale surface water source heat pump (SWSHP) systems despite available grants and incentives (that includes the Renewable Heat Incentive (RHI) see panel below). There is significant national and international legislation aimed at decarbonising the UK heat supply, and planning regulations often require new developments to include a proportion of renewable technology in order to reduce carbon emissions. An initiative by CIBSE, the Heat Pump Association and the Ground Source Heat Pump Association created CP2, the code of practice for surface water source heat pumps to provide a framework guiding the proper deployment of SWSHPs. This was aimed at increasing the opportunity of good quality applications of this wellproven technology to help meet the heat demand with reduced environmental impact. A measure of the potential for the deployment of surface water source heat pumps was detailed in research undertaken by Atkins1 (originally as part of the now-decommissioned UK National Heat Map project). This estimated the total heat accessible capacity from rivers alone at approximately 6GW in England, as illustrated in Figure 2, which equates to direct electrical heating by the equivalent of six ENSURING RENEWABLE HEAT INCENTIVE BENEFIT There are a number of requirements2 for an installation to benefit from the Renewable Heat Incentive (RHI) for electrically driven water source heat pumps. These include that the heat pump should have a coefficient of performance (COP) of at least 2.9 and a design seasonal performance factor (SPF) of at least 2.5 (based on heating and not cooling). For smaller installations (<45kWth), despite not being domestic systems, the installations must have Microgeneration Certification Scheme (MCS) certification or equivalent this is also required if any of individual heat pumps have a thermal output of less than 45kWth when several heat pumps USE a shared source loop. CIBSE Feb20 pp61-64 CPD v3.indd 61 Hinkley B nuclear power stations. The water source heat map document not only analyses the potential of water heat sources in England (as in the example map shown in Figure 3), but also includes an extensive commentary on the methodology to assess the feasibility of water sources. As part of Monitoring of Non-Domestic Renewable Heat Incentive Ground-Source & Water-Source Heat Pumps,3 produced for the UK government, the performance of several non-domestic water source heat pumps was monitored over at least one heating season. Since it was for a limited period and for relatively few installations (that were chosen from those registered for the non-domestic RHI4), the authors of the report are clear that the observed performance of this sample should not be taken as representative of the whole marketplace. However, their work identified aspects that impact all installations, a few of which are described here. As with the application of any heat pump (such as the 42kWth unit shown in Figure 4), the report notes that the main influence on heat pump performance is the difference between the temperature of the cold source as input to the heat pump and the www.cibsejournal.com February 2020 61 24/01/2020 15:13