For years, Northwards Housing utilised a district gas plant on the roof of its 1960s high-rise tower block to supply heating for residents at Clifford Lamb Court in Charlestown.
As the ageing gas plant’s energy supply became less reliable, coupled with the high levels of heat loss associated with high-rise buildings and overheating during summer, Northwards Housing turned to Ground Heat for a more cost and energy efﬁcient solution for their tenants. Northwards Housing required a renewable system that would not only meet the current needs of tenants, but one that would provide a future proof heating solution for the building.
Identifying the right solution
As a long-term Vaillant installer partner, Ground Heat was able to explore a range of renewable energy options, including biomass, air to water heat pumps and ground source heat pumps. As a large housing provider, approval for Northwards Housing’s new system needed to be approved by the local authority, as well as the District Network Operator, and a ground source heat pump became the solution of choice.
This would be the ﬁrst installation of its kind in the UK – traditionally used to service individual properties or serve heating from a communal plant room, individual ground source heat pumps had not been utilised in a multi-storey high-rise building before. The ground source heat pump required would need to be small to best meet the speciﬁcation needs of the building, as well as cause minimum disruption to tenants during the installation process.
Vaillant identiﬁed the geoTHERM mini 3kW as the best solution – unlike traditional ground source heat pump technologies, it uses single or shared boreholes for multiple properties and is also suitable for individual properties. Heat metering for billing purposes is not required, meaning tenants only pay for the energy they use as the ground source heat pump is wired directly into their own consumer units. What’s more, the compact wall hung unit includes ErP A-rated pumps.
The unit was sourced through Vaillant’s German operation and was re-purposed, with new software and modiﬁcation suggested by Vaillant in conjunction with Ground Heat and Northwards Housing, to suit the social landlord market.
The intricate project required specialist planning and installation and, as specialists in the ﬁeld, Ground Heat designed and installed two common brine risers from the ground, right through to the top of the building’s plant room with take offs incorporated to connect the 54 individual ﬂats.
Gas and electrical pipe work was uncovered during the groundwork, which added to the already challenging project. However, the installer was able to execute the works successfully and with great precision.
To maximise energy efﬁciency at the site, Ground Heat further developed a unique bore ﬁeld conﬁguration to guarantee higher coefﬁcient of performance (COP) throughout the year, which also greatly reduces the required run time of the bore ﬁeld. Ground Heat was able to utilise other renewable controllers from Vaillant’s extensive range to achieve this.
The ground-breaking installation has given tenants greater control over their energy and is reducing their individual fuel bills – collectively, the average savings will be around £6,804 per year. In addition, Northwards Housing’s service costs, associated with running heating systems in multi-storey builds, has been greatly reduced to around £250 a year.
Clifford Lamb Court’s annual carbon output has also been reduced from 97 tonnes CO2 to 52 tonnes CO2.
The total renewable energy installation also means that Northwards Housing can utilise the Commercial Renewable Heat Incentive (RHI) – with contributions through the scheme expected to exceed £400,000 over 20 years. The innovation behind the design also qualiﬁes it for the domestic seven year RHI if preferred.
Additional beneﬁts reported by tenants is an increase in hot water pressure – which can be attributed to the new gravity fed cylinders installed as part of the system. The install has also resulted in cooler corridors for the residents during warmer weather, which has been greatly appreciated.
The new system is covered by a seven year warranty, thanks to Ground Heat’s ongoing installer partnership with Vaillant.
David Thompson at Ground Heat comments: “As a long-term installer partner, we knew the brand would be able to deliver the right technology and support to enable us to deliver the most energy and cost efﬁcient system for Northwards Housing. This is a real ﬁrst for high-rises in the UK and although a challenging project, through continued support throughout the speciﬁcation and installation process, we’ve been able to deliver a ﬁrst class energy solution for the tenants at Clifford Lamb Court and demonstrate the full potential of renewable energy.
“The ability to ask direct questions to the right people during the design stage of ground source heat pumps is a must, even if the answers received may not be the answers we want to hear! This invaluable one-to-one approach with the Vaillant team is unlike any other manufacturer we have worked with over the last 12 years.”
Bernard Turner at Northwards Housing adds: “Relying on gas to meet the building’s heating needs was fast becoming a costly operation, for us as a housing provider and our tenants. Choosing an alternative energy solution would require a signiﬁcant investment from Northwards Housing so getting the right one was paramount. By adopting a partnership approach - with Northwards Housing, Ground Heat and Vaillant all working closely together from beginning to end, we’re able to deliver signiﬁcant cost and energy savings to our tenants now, and in the future, through the installation of the geoTHERM 3kW ground source heat pump.”