Bespoke hybrid renewable heating solutions are helping local authorities keep their tenants warm efficiently, explains Paul Wakefield.
Local authorities and housing associations are increasingly looking to environmentally and economically sustainable alternatives to heat their housing stock. Although it is fair to say that the majority of oil boilers can still tick the box for many off gas properties and probably will do for some time to come, a number of manufacturers offer greener solutions, such as air source heat pumps, to complement and often work alongside oil fired boilers as a hybrid heating solution.
A hybrid system is a combination of two or more efficient heating technologies, such as a boiler and a renewable appliance like a heat pump. These are packaged together to function as one unit, maximising system efficiency for the end user, whatever the weather. Grant UK is working with local authorities to make hybrid heat pump and oil boiler solutions practical and effective for their developments.
Hybrid models, such as the Grant VortexAir, unlock the benefits of green energy to off-gas developments. It combines an Aerona³ R32 inverter driven air source heat pump with an ultra low NOx VortexBlue blue flame oil-fired boiler and, in distress purchase situations, allows for the immediate restoration of a property’s heating while also enabling specifiers to introduce cleaner energy into their properties.
A Hybrid system provides contractors with flexibility when it comes to installation. In a retrofit or breakdown situation, the oil boiler and heat pump can either be installed at the same time or in two-stages, with the oil boiler installed first to quickly restore a home’s heat and hot water and the heat pump installed at a later date. Furthermore, the Hybrid’s oil boiler can either be sited internally as a stand-alone unit or externally alongside the heat pump depending on the availability of space. This Hybrid utilises an advanced control system that automatically monitors the system temperatures, seamlessly switching the unit to the most effective heating mode (heat pump, oil, or a combination of both).
Renewable products like heat pumps are also being improved to provide better efficiency. The 2014 EU Fluorinated Greenhouse Gas (F-Gas) Regulations is legislation designed to phase out the use of hydrofluorocarbons, with the introduction of a series of targets designed to limit the use of gases with the highest Global Warming Potential (GWP). R32 refrigerant, which is used in Grant’s latest Aerona³ heat pumps, has a GWP considerably lower than other typical heat pump refrigerants such as R410, thus complying with legislative targets.
In addition to having a lower GWP figure of 675, R32 is a single-component refrigerant, which means it has no temperature glide. Refrigerant blends that have two or more components exhibit temperature glide but as R32 only has one molecule in its formation, its saturated liquid and vapor temperatures are the same. By removing the risk of the refrigerant suffering from glide, the system can recharge and recycle with greater ease, making it more efficient.
It’s important that local authorities work with manufacturers to design efficient and effective heating solutions for schemes. Recently for instance, Grant UK worked with a local council to replace the solid fuel heating systems in their properties with hybrid technology.
As part of this solution a bespoke hybrid system was designed, comprising a 6kW Aerona³ R32 heat pump with a 15/21kW VortexBlue oil boiler. This combination of a 6kW heat pump with an oil boiler is not part of our main Hybrid range offering but it demonstrates how we can provide tailored heating solutions to meet a development’s needs. By partnering with a company that offers multiple solutions, from oil-fired to renewable heating options, social housing providers can benefit from their expertise and insight ensuring the most appropriate technologies are utilised on projects.
Grant’s renewable technology has been specified for numerous local authority and housing association schemes, for example Hebridean Housing Partnership installed 77 heat pumps, replacing existing solid fuel systems with this low carbon form of heating. Easy to install and ideal for housing associations, hybrid solutions are definitely a heating solution to keep in mind.
Paul Wakefield is Managing Director for Grant UK