News Articles
19 August 2009
SAV MINI CHP SYSTEM DRIVES GREEN ENERGY SOLUTION
One of the country’s most desirable retirement developments utilises the low carbon, energy saving benefits of an SAV LoadTracker combined heat and power system.
Electricity, space heating and hot water for domestic services in the main building at award winning Bramshott Place Village are all generated by the gas-fired CHP system.
Bramshott Place Village at Liphook in Hampshire was conceived by developers Helical Bar and Urban Renaissance Villages as a retirement village for active over-55s. Apartments and cottages will be combined in a total of 147 homes centred on an exclusive country club. Central facilities include a health centre and pool, a bar and restaurant and the spacious Atrium Winter Garden.
The project has won an award in the NHBC’s Pride in the Job scheme.
All that remains of the original Elizabethan Bramshott Grange is the Grade ll* listed gatehouse - now fully restored as part of the development.
It’s a Tudor gateway to the finest the 21st Century can produce in the form of controlled, low energy environmental comfort.
The CHP system is linked with other SAV System’s products - including instantaneous hot water generation and underfloor heating manifolds. The result is a perfect synergy with the current drive to reduce the carbon footprint of UK buildings.
Heart of the system
At the heart of the system is an XRGi-15G mini-CHP machine, part of the EC Power range marketed in the UK by SAV Systems.
This rugged machine, with its ultra-reliable Toyota gas-fired engine, can provide 6-15 kW electricity and 17-30 kW heating. And there’s no need to export spare electricity to the grid – there is no spare electricity!
With electricity needed for power and lighting the main building at Bramshott Place has a round the clock energy requirement, although demand reduces at night time. Electricity generation matches load over each 24-period with the unique modulating system ensuring that the electricity generated never exceeds demand. All the energy generated is used.
Waste heat generated by the mini-CHP unit is fed through a special heat exchanger and used to heat water, which is stored in a thermal store at around 80oC. Water from the store can be drawn off to provide heating and domestic hot water services as required.
The CHP plant also makes a contribution to heating the water in the clubhouse swimming pool.
Instantaneous hot water
SAV Systems has supplied Danfoss heating and hot water substations for the underfloor heating system and instantaneous hot water in three apartments within the main building. These units bring a dramatically improved level of energy saving heat transfer efficiency to domestic hot water supplies. Because hot water is only generated when it is required there are no storage losses in the system. No separate storage cylinder is required, yet hot water is instantly available.
Indirect versions of the kind to be used at Bramshott feature a second heat exchange module, which acts as an interface between the hot water main supply from the CHP system and the circuits within the building.
Energy automatically diverted
The Danfoss substations are close-coupled on back plates with SAV underfloor heating manifolds connected to the hidden loops of pipe serving each apartment. A further 10 manifolds supply the loops of underfloor heating pipework serving the other areas of the building.
When a variation in pressure is detected - as a result of an opening tap - the thermostatically controlled system ensures an instant supply of DHW. Energy is also automatically diverted via the heat exchanger from the heating circuits to the hot water supply - reverting back to the original setting when demand ceases. The system is designed to run smoothly – with no wild fluctuations in temperature or pressure on either heating or hot water circuits.
Diverting energy to hot water supply is much more efficient especially at times of peak demand – and also ensures the low return water temperature, which is ideal for the efficiency of the CHP system.
Moreover, constant modulating control can ensure that energy is directed in exact proportion to demand.
Energy and water consumption of each apartment is measured by meters supplied by SAV with data automatically transmitted to a Hydrocentre 25M datalogger. Information can be subsequently downloaded from the Hydrocentre for billing and monitoring of overall system efficiency.
Data from the daily operation of the CHP system can be read on site and is also transmitted via the internet to the monitoring station in Denmark, operated by SAV Systems for all EC Power CHP projects.
All of the homes at Bramshott Village are equipped with SAV underfloor heating manifolds and are designed to make the maximum use of solar power in generating domestic hot water.
Building services engineers for the project were tga Consulting Engineers of Stevenage and main contractor was the Ardmore Group.