Case Study: Edgbaston Priory Tennis Club
Forming part of the £11 million development of the Edgbaston Priory Tennis Club, six new indoor tennis courts required a low energy heating system, which could provide zonal heating and reduced energy consumption without sacrificing comfort for the players. Used at hundreds of sporting facilities across the UK, Nor-Ray-Vac continuous radiant tube heating from AmbiRad, part of Nortek Global HVAC (UK) Ltd proved to be the most efficient system for the centre, providing considerable cost savings over its lifecycle.
Creating a year round tennis facility available for the use of both professionals and amateurs alike, this new indoor tennis centre has been designed with an emphasis on natural daylight, reducing energy consumption levels. To further the buildings eco-credentials, AmbiRad worked with a specialist contractor Kershaw Mechanical Services Ltd on a stand alone, energy efficient radiant tube heating system, which would provide a heating zone for each court in the scenario where few courts could be in use at any one time.
Traditional sports hall design presents particular challenges when it comes to maintaining a comfortable environment. In one vast, open space, the requirements of all users, from athletes to spectators, must be fully satisfied. The aim is to create an environment without stiffness where occupants can exercise vigorously in complete comfort.
Achieving universal comfort and low energy consumption therefore demands a heating system that:
- Offers a rapid response to changed conditions
- Has frugal energy consumption
- Can be ‘zoned’ to heat only those areas in use
- Operates at low noise levels to comply with BB93
- Will not compromise the fabric of the building
EU and UK legislation also has an impact on the choice of HVAC system. Becoming ever stringent, it requires modern heating systems to optimise fuel efficiency and produce lower greenhouse gas emissions.
While conventional boiler and distributed radiator or under floor systems frequently fail to provide the flexibility or speed of response needed in today’s multi-use halls, highly economical radiant tube heating is an effective solution. In fact, no other heating system currently in use in sports halls can match it for energy efficiency.
Since radiant tube heaters burn fuel at the point of use, heat distribution losses are eliminated and there is no requirement for a separate plant area. The warming effect can be felt within just a few minutes of switch-on, even on the coldest days. Mounted at high level, the heaters are well out of the way of sports equipment and can be covered with safety grilles to protect them from high flying balls, for example.
The ideal solution for sports halls
Like the sun, radiant tube heating emits infrared rays, which warm only people and objects in their path. This type of heating is therefore ideal for sports halls because it ensures even heat coverage throughout the space and the comfort of the building occupants, regardless of their level of activity.
No energy is wasted heating the volume of air – an important factor in buildings which are typically around 600m² with roof heights of 8-10m. Similarly, heating 5,000m³+ of air to ensure people are warm at the lowest 2-3 metres is not feasible in terms of fuel-efficiency.
Radiant tube heating’s big advantage is that air remains relatively cool and conducive for active sports. Air does absorb some of the heat given off by people and the building fabric at low level, but it is not heated directly so the occupants are comfortable. If they should feel too warm, the close control possible with radiant tube heating means that temperatures reduce immediately once the system is turned down or switched off.
For the 83m x 51m facility, Nortek provided the Nor-Ray-Vac system with 24 x 24 LR burners designed in six zones to provide a zone per tennis court and suspended at 7m above the finished floor level. These were all connected to two off vacuum discharge fans remotely mounted on the roof.
The Nor-Ray-Vac radiant heating system is ideal for sports facilities as it not only offers a rapid response to changing conditions but also because it does not have to operate 24/7, providing the end user with low operating costs. Additional benefits of the stand-alone system for the club are the low air temperatures making it conducive to sports activity and offering no risk of stuffy conditions.
This energy efficient system combusts the fuel at the point of use, resulting in no distribution losses and virtually instantaneous heat. In complying with the requirements of the European Gas Appliance directive (EN777) they have reduced running costs and qualify for inclusion on the Energy Technology List and thus qualifies for Enhanced Capital Allowance.
Following the handover of the facility in 2012 the new indoor tennis centre at Edgbaston Priory is now providing members and the community with a world-class facility as well as new additional features including squash courts, gym and leisure facilities.
Benefits of Radiant Heat / Nor Ray Vac in Sports Facilities
- Achieves a comfortable environmental temperature with approx. 5°C lower air temperature, ideal for active sports
- Condensation on walls or floors should always be eliminated, as this can be dangerous and poses a threat to player safety. Nor-Ray-Vac eliminates condensation and moisture by directly heating walls and other surfaces.
- Radiant tube heaters mounted overhead, produce infrared radiant heat that is directed downward by a reflector. The infrared heat passes through the air without heating it and falls on people, floors and equipment below by creating a comfortable all round radiant warmth at low level, without wastefully heating the whole volume of the building or the roof space.
- Maximises efficiency, as the fuel is combusted at the point of use, thus eliminating any distribution losses
- The objective of a radiant heating system is to ensure that the people in the building are comfortably warm.
- The human body experiences a sensation of comfortable warmth when it is giving heat to its surroundings. If the body emits too much heat it feels cold. Conversely, if the body cannot emit sufficient heat it feels too hot. By the correct application of radiant heating system comfort levels can be optimised.
- Radiant heat warms objects and surfaces, increasing the mean radiant temperature and reducing the body’s loss of heat to its surroundings. In addition by eliminating air movement, convective loss of heat from the body will also be reduced.
- By heating without air movement, increases player comfort and is essential for badminton
- Warms muscles prior to strenuous activity
- Provides rapid response times to changed conditions.
Radiant tube space heating is proven to meet the HVAC challenge posed by sports halls, reducing fuel consumption without affecting comfort levels to deliver sustainable cost savings over the long term.
When designing an AmbiRad Nor-Ray-Vac system, Nortek Global HVAC considers the following criteria:
- Heat loss of the building for the required thermal environment
- Local climate conditions
- The type of activity conducted within the building
- Specific architectural features relating to the structure
Installation Summary:
- AmbiRad Nor-Ray-Vac continuous radiant tube system
- Uniform blanket heat coverage
- Highly efficient with rapid heat recovery times
- Zoning capabilities
- Operative temperature; 16˚C – for sport activity
- Potential savings of 75% equivalent to 2,170 metric tonnes of CO²
Technical Summary:
- Product: AmbiRad Nor-Ray-Vac system installed at 7m above finished floor level.
- Heaters: 24 x 24LR burners
- Control –Dimensions – 83m x 51m ports hall
Trademarks AmbiRad, Reznor, Airbloc, NordairNiche and Benson used under license.