Bespoke installation of Rehau Awadukt Thermo ground – air heat exchanger
REHAU has installed a bespoke version of its AWADUKT Thermo ground – air heat exchanger system at a new special educational needs secondary school in Peckham, Southwark, specifically designed to overcome any potential risk from methane below ground.
The REHAU AWADUKT Thermo system works by drawing ventilation air through a network of pipes laid at a depth of around 1.5m, where the natural temperature of the earth is between 8º and 12ºC all year round. The optimised polypropylene material used for the pipework maximises the heat transfer between the ground and the air with the result that when the air is delivered into the school it is pre-warmed by up to 9ºC or pre-cooled by 14ºC depending on the season.
The system will deliver air flow rates of 9,000m³/h of pre-tempered air to help maintain comfort levels in the school.
On the Tuke School site, REHAU worked closely with consultants Building Design Partnership (BDP) to design the fabricated header pipe and supply special NBR sealing rings for AWADUKT Thermo which eliminated any risk of methane ingress.
BDP had specified concrete ducts in ground – air heat exchanger systems on previous projects but judged that the sealing rings on concrete pipework would not be adequate on the Peckham site and chose the REHAU solution instead.
Steve Richmond, Product Manager for REHAU’s renewable energy systems said: “REHAU’s expertise is in the development and application of polymer technology. On this project, that was demonstrated superbly with a specially fabricated 1000mm header pipe with 500mm sockets and special NBR sealing rings. This is coupled with five 36m long runs of 500mm AWADUKT Thermo polypropylene pipe lined with an antimicrobial layer made from silver particles which prevents the build up of microbes.”
Tuke School has been designed by architects Haverstock Associates LLP for Southwark Council with a raft of ‘green’ features including a sedum roof and ground source energy supply. The design was rated ‘good’ by the CABE assessment panel and incorporates many sensory elements for the 90 pupils who have a range of learning disabilities.
The REHAU AWADUKT Thermo system has been installed below the main building of the school by Balfour Beatty. Balfour Beatty is responsible for the £200million Southwark Building Schools for the Future PPP project which involves the delivery of a major capital investment programme over three phases covering 12 schools across the borough.
REHAU AWADUKT Thermo has been used extensively in facilities for the disabled since it provides a quiet and effective source of renewable comfort cooling. It has already been used, for example, in the Pears National Centre for Autism Education in Muswell Hill, the Lisburn Assessment and Resource Centre in Northern Ireland and Nairn Academy in Scotland.