The Renewable Heat Incentive (RHI) will provide attractive rates of return for installations at larger residential properties and outlines how high output single phase heat pumps can provide an especially appealing solution.
The long-awaited launch of the domestic RHI should create many opportunities for contractors offering ground source heat pump installations. That said, much work still needs to be done by the government and other stakeholders to publicise the scheme to the wider public. In the meantime, savvy installers will focus marketing activity on those prospects most likely to find an installation appealing. And that means householders living in larger properties away from the gas grid.
These substantial dwellings – especially those larger than 250m2 – benefit from DECC’s decision to offer an identical RHI tariff regardless of installation size. Unlike the Feed-in Tariff, which recognised that a lower tariff should be paid to larger installations which benefit from a lower cost per installed kilowatt, the RHI tariff is consistent across all eligible installation sizes and is merely varied by the presumed efficiency of the installation. That approach inevitably favours larger dwellings, especially if the properties have sufficient land to support a trench-based ground array or, better still, feature a lake which can accommodate pond mats.
More importantly, it is vital that the householder can benefit from DECC’s decision to pay this tariff on the deemed energy consumption (kWh/yr) taken from an Energy Performance Certificate. This approach can be adopted whenever the heat pump can handle the property’s entire heating requirement, in accordance with the latest MCS requirements, and provides a certain financial return. Wherever a fossil fuel boiler back-up is necessary, the heat pump’s output must be metered which eliminates certainty, adds cost and requires more ongoing administration.
Of course, larger houses are often fitted merely with a single phase power supply which means installers will benefit from partnerships with the select manufacturers offering high output single phase products; some offer 24kW models which can eliminate the need to invest in a costly three phase power supply. In addition, it is possible to purchase twin compressor machines which use different refrigerants in each compressor circuit to provide the optimum balance between high outlet temperatures and high thermal capacities.
The RHI creates some appealing possibilities. Unlike the FiT-based technologies, which can only offer a projected income based upon the likely levels of sun and wind, the RHI income is guaranteed whenever the criteria for the deemed approach is satisfied. Rates of return are enhanced by the use of low cost high output single phase heat pumps and will be especially generous if lower cost ground arrays can be used. And that has to be good news for contractors supported by knowledgeable manufacturers who can provide the necessary expertise to deal with large, complex properties.
Simon Lomax is managing director at the Kensa Group, and chairman of the Ground Source Heat Pump Association