Beaufort EERP Project – 58 Units & Day Care Centre – Dun Laoghaire Rathdown Co. Co.
Beaufort EERP Project – 58 Units & Day Care Centre – Dun Laoghaire Rathdown Co. Co.
Dun Laoghaire Rathdown (DLR) County Council working with SSE Airtricity Energy Services has a strong history of working together to deliver successful Energy Retrofit projects in the DLR area over the last number of years. One of the most recent of these was the upgrade of 82 DLR units in Quarter 4 of 2022 which included the Beaufort residential care project. Originally built in 1984, the Beaufort complex in Glasthule, Co Dublin consists of 58 residential units across three blocks including a day care center and kitchens. The upgrade works involved improving the units from an average BER E1 – to an average A3 rating. SSE Airtricity was appointed as the primary contractor and were responsible for surveying, designing, preparation of the bill of quantities in conjunction with DLR county council, tender evaluation and contractor appointment, project management through to completion, commissioning, and delivery of the necessary post evaluation BER’s and certifications.
The project scope was to upgrade 58 largely single dwelling units and adjoining day care center involving the installation of new windows and doors, external wall insulation, Attic insulation, installation of Solar PV, Mechanical ventilation, heating controls and LED lighting. It also involved the blocking up and reducing the height of individual units’ chimneys.
Measures installed included:
- Install of centralized Heat Pump system with individual timers and thermostats in each unit
- External wall insulation Incl., altering all existing services as required
- Attic insulation
- Solar PV & i-Boost
- Install of new 140 KVA Electrical Feed
- Full time PSCS on site
- Supply & fit A-Rated windows and doors throughout
- New high retention hot water cylinder
- Facia and soffit/downpipes/ replaced
- Ventilation to homes
- Smoke and Carbon Monoxide alarms
Each unit was fitted with new windows and doors and externally wrapped with 5 x 405w Solar PV panels, amounting to 2.025kwp per unit, connected to an i-boost system for control of individual unit hot water cylinders. Of the 58 units upgraded, 48 received an A rating with the remaining 10 receiving a B rating, achieving an average post work calculated energy saving of 275Kwh/m2/yr per unit, a reduction of up to 80% in total energy usage. The upgrade works included the upgrading and modernizing the heating systems pipework within each of the units, including the decommissioning and removal of old gun barrel metal pipe work. All works were carried out with the residents in situ, involving the strong communication, project co-ordination and project and site safety management of contractors etc. to minimize disruption and disamenity to the elderly residents.
The major innovation in the project was the installation of a centralized heat pump system. The original heat source for the individual units was a centralized gas fired boiler which fed the individual residential units and day care center. In upgrading these units, we replaced the original centralized gas fired heating system with a centralized multi-unit air source heat pump system. The heat-pump system for the apartments was designed for space heating only, the hot water being provided through Solar PV i-Boost with a backup immersion if necessary. As the units are single occupancy the hot water demand is low, so the backup immersions are unlikely to be required. The day-care center and kitchens (on the same premises) now run from an independent 14kw Ecodan heat pump system for space heating and hot water, as this area is not in use 24/7.
The initial solution proposed for the single dwelling units was a centralized system using 3 x individual 43kW heat pumps (one for each block). On review it was decided against this for resilience and efficiency purposes as individual units would have no back up in case of failure leaving the predominantly elderly/vulnerable residents with a potential “no heat” situation if a single unit failed. Instead, it was proposed to install an amalgamated system of eight cascaded 14kW Ecodan heat pumps with a combined capacity of 112kW.
The benefits of this unique cascade solution are:
- It would provide greater failsafe protection i.e., if one unit (of the eight) fails there are seven more in place to make up the loss. Thus, ensuring the elderly/vulnerable customers have a secure, comfortable, and warm environment 24/7. Also, these smaller units are more prolific and therefore need less specialized servicing.
- The cascade system would also provide far greater efficiency at low heat demand times. The 14kW units were installed in two parallel series of 4 heat pumps each. Meaning during low heat demand times (e.g., in summer) each series can be modulated down to one operational unit at a minimum output of 3kW giving a total minimum load output of 6kW for the total system. This compares very favorably to a minimum, modulated load of 18kW for a traditional cascade 43kW CAHV system.
- The cascade system yielded higher deemed energy credits from a post BER evaluation perspective. Unfortunately, the commercial 43kW CAHV systems are not certified for domestic installations and therefore the deemed default energy credits would have been 250 per unit versus 420-480 per unit for the cascade 14kW Ecodan system.
- The cascade system avoided the cost and inefficiencies of installing 54 individual heat pumps for each residential unit.
Allbrite Heatpump Specialists Ltd from Monaghan, Mitsubishi dealer partners verified the proposed design with their design team running the calculations, and confirming the energy efficiency benefits.
As this system was the first of its kind installed in Ireland and a completely unique heat pump space heating solution, Allbrite carried out the installation and commissioning of the system to guarantee balance and performance given the unique nature of the design.
The installation also required ESB Networks to upgrade the feed-in cable from a 70Kva cable on site substation to a 140Kva cable to facilitate the additional electrical load of the heat pump installed system.
This level of innovation, intricate design, attention to detail and collaboration is what sets this DLR County Council and SSE Airtricity project apart from other retrofit projects in the market. The residents were kept informed throughout the project with regular communication and had a dedicated residential liaison person available on a dedicated hotline. All residents were trained on the use of their hot water and thermostatically modulated heating controls.
The total cost for the upgrade of 58 units in Beaufort this project was circa €2.6 million at an average cost of €45,000 per unit. There was reduction in calculated energy usage of circa 80% on the pre-energy usage, or an average saving of 7,998 kWh per unit or a total 463,900 kWh saved per annum.
Catherine Keenan, Director of Housing, Dún Laoghaire-Rathdown County Council –
“This project in Beaufort is a district heating system so it’s a cascading system of eight heat pumps that services the entire 58 homes and what’s different here really is that the Department of Housing, Local Government and Heritage was providing a system whereby we would provide heat pumps in individual apartments or houses so this way we were able to half that cost by providing the cascading system that we did. The department agreed to that on a pilot basis so it’s the first of its kind in the country.”
