Air conditioning is at the heart of sustainable energy strategy
At the heart of the energy strategy for a new college in Suffolk is storing heat extracted from the building during the Summer to heat it in the Winter.
Suffolk One, the recently completed iconic college located in Ipswich, has one of the most advanced and eco-friendly building-services systems in the world. Opened last year following an investment of £65 million, this building is designed to provide an inspirational learning environment for over 2000 students from south west Ipswich and south Suffolk.
There is a vocational training block to the north and ‘teaching clusters’ to the south, with an airy central atrium running throughout its length. All teaching areas are designed as flexible work spaces with multiple high-level skylights flooding natural daylight into working areas.
The central space includes an eating area and communal breakout zones for informal study. There is also a double-height performance space plus a 6-court sports hall and multi-use games area, with access for the local community.
The building is orientated to reduce solar gain. External shading is used at the entrance, and there is solar control glazing on south-facing clusters.
Behind its architectural design is a building-services solution that harnesses advanced and sustainable technologies available.
Because of its location near a major road intersection, acoustic constraints required the use of sealed windows, making mechanical ventilation and cooling necessary for about 65% cent of the building. A combination of ground-source heat pumps, evaporative cooling and high efficiency gas-powered DX heat-pump air conditioners provide low-carbon, year-round comfort conditions for students and staff.
The ground source system uses some 14 km of pipe work laid underneath the college’s bus turning area so as to collect solar energy. Thermal energy collected from this array and from the building during Summer is stored in 18 bore holes 100 m deep and used to heat the building during the Winter via an underfloor heating system that extends throughout most of the building. Heat recovery enables a high proportion of heat energy to be recycled to warm incoming fresh air. Three roof-top-mounted evaporative cooling systems are used to cool the sports hall.
On the DX side, Suffolk One is the first building in the UK to use Sanyo’s gas-powered co-generation VRF air-conditioning system, which can also generate its own electricity. At 20 200 m2, this project is the largest site in the country using this gas-powered heat-pump VRF air conditioning.
The £11 million M&E installation was managed by Inviron and includes air conditioning with a combined cooling capacity of 1.2 MW. The Sanyo system was supplied by specialist ESS and installed by Adcock Refrigeration & Air Conditioning.
The size and distributed nature of the building required 19 GHP VRF air-conditioning systems and 16 high-efficiency split systems. The units are mounted primarily on the roof, in groups serving the clusters which connect and surround the core of the building.
There are 310 fan coils, mainly ducted units mounting in ceiling voids and a few ceiling cassettes. All equipment R410A refrigerant.
The VRF systems include both 2- and 3-pipe technology, the latter used to harness waste heat generated within glass-clad parts of the building and transfer it to areas requiring heating.
Michael Peachey, director of estates and commercial services at Suffolk One, said, ‘It provides an outstanding place of learning for students and an exceptional environment in which to work
‘We opened our doors in September 2010 and have therefore not yet completed a full year of operation. The building-services system is designed to optimise efficiency over the course of a year, collecting and storing waste heat in the Summer and tapping and harnessing it to heat the building in the Winter. It is a pioneering approach that could set the direction for sustainable buildings in the future. Students are able to incorporate the design and operation of the systems into the project work to support their curriculum.’
Wayne Blunden, who heads the Norland Managed Services facilities-management team at the site, says. ‘It’s a highly creative and sustainable design, not just in the use of low-carbon technologies but in the way they combine and support each another.’
He adds, ‘The key, in terms of both energy efficiency and comfort conditions, is optimal balancing with high-level intelligent control. This is taken care of by an overarching building-management system. The contributing systems will be tuned over the course of time, in line with load conditions generated by use of the building and in relation to changing seasons. As with any new building, this is a learning process and requires ongoing calibration as use of the building evolves.’
Given the educational focus of the building, a key design issue was low sound levels. The libraries and classrooms require a very low level of background noise, which was comfortably met by the Sanyo equipment.
Adrian Bonfield, branch manager at Adcock in Norwich, who managed the installation, said. ‘It was the first GHP installation we had undertaken, so to some extent we were on a learning curve. However, the back-up and support from ESS was excellent, and the project went without a hitch. It is top-notch equipment with completely professional support.’
Bob Cowlard, sales and marketing general manager for Sanyo Air Conditioners, said. ‘This is without doubt a landmark project. The ESS team has done a great job in delivering a solution perfectly matched to the need. We see this as an exemplary forerunner for the wider roll-out of the new GHP and co-generation technology across the UK and Europe.’