Welcoming students from all over the world, Concord College in Shropshire is a highly academic international school for students between 13 and 19 years of age. Concord’s dedication to the highest standards is evident in the facilities on its 80-acre campus, which operates seven days per week, because 85% of the students board there. When the college recently committed to building a new, three- storey student accommodation block with 65 bedrooms, for environmental and economic reasons, it opted to adopt renewable energy sources.
Combining renewable technologies
Concord College was already using renewable energy to heat areas of the campus and was certain its new accommodation block should also use renewable energy in some form. To be sure the college invested wisely, that optimum technologies would be utilised and energy efficiency would be future-proofed. The college stipulated that whatever equipment was adopted would have to leave enough space for future expansion, and that the building must be ready for students at the start of the new school year in September.
Five Viessmann Vitocal 300-A air source heat pumps, where installed in a modulating cascade system, as the primary heat source for the building. These provide warmth to all rooms via underfloor heating and low temperature radiators. The Vitocal 300-A is the first air/water heat pump with digital scroll technology and an electronic bi-flow expansion valve, which means it achieves an extremely high coefficient of performance (COP) of 5.0. The resulting energy efficiency reduces running costs considerably compared to traditional heating methods.
For the provision of domestic hot water, the outdoor air source heat pumps are combined with 12 Vitosol 200-FM solar thermal panels, integrated into the building’s roof. The Vitosol 200-FM has Viessmann’s unique and patented ThermProtect coating technology, which prevents overheating and system stagnation, leading to longer runtimes and lower maintenance. Concord College is the first site in the UK to take advantage of this technology.
For those occasions when heating and hot water demands are exceptionally high, the air source heat pumps and solar thermal panels are backed up by two 129 kW oil condensing boilers. Hot water is stored in four Vitocell 300-B twin-coil DHW cylinders, each with 500 litres capacity, which are situated in the building’s plant room.
These three sources of heat and domestic hot water are managed by Viessmann’s Vitotronic control system, which enables multiple heating sources to work together seamlessly, always choosing the most efficient method first.
Following completion of the accommodation block in September 2016, Concord College is expected to save £5,000 per year in fuel bills compared with a system that is exclusively oil-fuelled. A further financial gain of £10,000 will be made every year because the system is eligible for payments from the government’s RHI (Renewable Heat Incentive) scheme, which provides a payback period of 7 years. More than this, though, it is also important to the college that the renewable technologies in the new accommodation building will reduce its carbon emissions by 42 tonnes annually.
The integration in the new accommodation block of these exceptionally efficient Viessmann technologies has been so successful that Concord College is now looking at similar systems for future expansion projects