Colchester City Council’s energy-efficient refurbishment

Energy-efficient heating, cooling, and hot water generation systems manufactured by Mitsubishi Heavy Industries Air-Conditioning Europe (MHIAE), part of the MHI Group, are helping Colchester City Council to achieve its sustainability goals.

The council secured £572,000 of funding from the Public Sector Decarbonisation Scheme towards a major refurbishment of its Rowan House HQ.

Pam Donnelly, Chief Executive of Colchester City Council, said:

Rowan House is a testament to the council’s vision and commitment to environmental sustainability. Our aim was to create a workplace that reduces our carbon footprint and inspires our staff and the wider community to embrace sustainable practices. We believe that by leading by example, we can encourage positive change and make a lasting impact on our environment. We are immensely proud of Rowan House and the opportunities it presents for collaboration, innovation, and a greener future.

The works were carried out by developer M3 Developments and M&E contractor Rossair, supported by MHIAE’s specification team and supplied by one air conditioning and refrigeration equipment wholesalers, HRP. The council’s existing gas boilers and water heaters were replaced by MHI VRF heat pump units (which provide independent on demand heating or cooling to all areas) and a Q-ton air-to-water heat pump for hot water generation.

James Morrison, Project Manager for Rossair, said:

The biggest challenge was getting all the kit into the designated areas, as we only had small spaces to work with. Sizing and positioning the condensers and placing the indoor units in the existing ceiling tiles were key to the client’s demands.

A total of 13 3-pipe VRF heat recovery systems from the second generation KXZ range, with capacities from 28kW-67kW, were connected to 105 indoor standard and compact cassettes and wall mounts.  The KXZ range offers cooling capacities from 22.4kW-67.0kW. The modular outdoor units can also be “twinned” or “tripled” providing up to 168.0kW on a single system. The range has a total piping length of 1000m, and the furthest indoor unit can be connected up to 220m from the outdoor unit. The units offer high levels of design flexibility, which helped to simplify the installation process.

MHIAE’s 30kW Q-ton heat pump is distributed in the UK and Ireland under a joint venture with Beijer Ref. Installed at Rowan House with a 1000-litre storage cylinder, it operates using CO2 – a natural refrigerant with a global warming potential (GWP) of less than 1 – and produces hot water between 60°C and 90°C. The Q-ton can operate down to ambient temperatures as low as  at -25°C ambient temperature, with no loss in capacity to -7°C. It is WRAS approved and achieves two BREEAM design points (three when fitted with leak detection) as standard.

It is supported by a Q-ton Remote Monitoring System (QRMS), which checks operation and provides weekly and quarterly reports comparing energy usage and efficiencies against gas and electric equivalents and self-analyses to highlight any potential operational or maintenance requirements.

The replacement heating system is expected to save an estimated 108.7 tonnes of CO2 and the LED lighting 30.9 tonnes of CO2, per annum.

The project will also make significant contributions to other key elements of the council’s strategy, including leading on sustainability, improving air quality, encouraging green technologies and innovative solutions to climate emergency, and ensuring the council’s assets continue to contribute to economic growth and opportunity.

For more information on building retrofit, visit InstallerSHOW 2024, 25 to 27 June at the NEC. Register for FREE tickets here: installer-2024-splash.reg.buzz