Natural ventilation is a key element in ‘very good’ BREEAM rating
A combination of controlled natural ventilation and air conditioning is helping Capital Print achieve a ‘very good’ BREEAM rating for its new custom-built premises, where it is moving to after being displaced from the 2012 Olympic site. The Capital unit is one of four on the site at Beckton Waterfront with Passivent’s mixed-mode system — which harnesses natural forces to efficiently ventilate the building, supplemented as appropriate by air conditioning. The Passivent system is the leading element of several sustainable strategies being used by Capital — including solar photovoltaic and solar water heating. Overall, they are reducing Capital’s carbon emissions by 12.7%, compared to the Government target of 10%. The Passivent ventilation system comprises 16 Aircool wall ventilators, which draw fresh air into the offices on the ground and first floors and into the meeting room on the first floor. Nine suspended ceiling louvres draw the fresh air across the depth of the room and exhaust air up concealed ducting to nine Airstract high-capacity roof terminals. The system provides some occupant control via over-rides in individual rooms. There are also internal sensors for temperature and carbon dioxide, linked to an external weather station that monitors the external air temperature, wind speed and direction. The entire ventilation strategy is controlled by a programmable logic controller that constantly monitors air temperature and quality in the building and adjusts ventilation levels as required. If the internal temperature is above or below setpoints, the air conditioning is brought into play. Passivent natural-ventilation systems are driven by cross ventilation, warm air rising and the venturi effect of wind passing over the outdoor terminals drawing air from the building. The system can operate overnight to provide free cooling when the building is not occupied to reduce energy consumption by up to 40% the following day. Tests by Brunel University showed that Passivent’s mixed-mode system delivers energy savings of 41% compared to a conventional air-conditioning and ventilation system. Natural-ventilation systems also yield 75% saving on maintenance costs and eliminate the need for a central plant room. Rav Gill of Capital Print comments, ‘As a company, we have long been committed to choosing the most environmentally friendly path, so the relocation gave us an opportunity to custom build and incorporate features designed to conserve power and minimise carbon emissions. Passivent’s mixed-mode system gave us a low-carbon solution to ensure all our offices and meeting rooms are well ventilated throughout, but always at a comfortable temperature — neither too hot in the summer or too cold in the depths of winter.’For more information on this story, click here: May, 08 120
