Animal instinct drives BMS uptake
The intelligent use of modern building management systems (BMS) is increasing at facilities emanating from an ever-widening number of sectors. Far from the conventional preserve of education establishments, historic buildings, office blocks, hotels, hospitals and sports centres, the latest BMS technology is being introduced at several unusual and perhaps slightly surprising end user sites, including zoos and large cultivation greenhouses to name but two.
The uptake of interest in the management and control of the electrical and mechanical function of buildings is rising for a number of reasons. In most cases the principal reason is cost. The successful implementation of BMS technology not only leads to a more energy efficient building, but also to better management of labour resources. Additional benefits include the reduction of carbon footprint and the creation of a comfortable and healthy environment.
Realising the advantages on offer, an increasing contingent of more diverse facilities is beginning to adopt the BMS ethos. Zoos and wildlife parks for instance are generating increasing business for market leaders in the BMS field, such as Priva Building Intelligence Ltd. Priva can cite a number of recent examples where the prime beneficiaries of BMS technology are animals rather than humans.
A case in point is Bristol Zoo Gardens, where a recent project to revamp the Reptile House involved replacing outdated manual equipment with a Priva Top Control BMS. The brief included producing temperature and lighting profiles for 17 separate vivariums containing reptiles from around the world, including a number of rare species.
To get things right, Priva programming engineers worked closely with building services consulting engineers, Bristol-based The Brodie Partnership, and controls specialist/Priva partner, Controlco Ltd of Gloucestershire.
The three companies devised a control strategy that manages a number of simulated effects intended to replicate the natural habitat of each reptile. These include fluorescent tubes providing background daylight for the vivariums, where the daylight is adjustable throughout the year using a calculator function available in the Priva tools. Similarly, a spotlight to replicate the sun is on for varying amounts of time.
From a temperature perspective, sensors monitor each vivarium, while a time control allows lower temperatures overnight. There is even a pool pump that passes water through a filter and has a flowing water effect.
All of the vivarium systems are linked together through web browser software, with each vivarium having a separate page with time channels for each control output. Added functionality is provided by Priva’s TC History product, which retrieves selected information online from logged data stored over a period of time. The information is saved in an open database from where it can be used later to better inform zoo staff in terms of giving useful data for breeding programmes and behavioural studies.
A hundred miles southwest, a similar project has been welcomed by the six crocodiles, four boa constrictors, one reticulated python and numerous turtles at the new Crocodile Swamp at Paignton Zoo Environmental Park. Here, Priva partner Ecotech UK worked closely with project consultants Hoare Lea’s Plymouth office.
“Managing a wildlife environment is much more demanding than, say, an office,” says Ecotech’s Technical Manager Duncan Grant. “If employees are uncomfortable they can complain to the facilities manager, whereas a poor environment for animals can not only be uncomfortable but can directly affect their health.”
At the Crocodile Swamp, a Priva Compri HX8E with additional I/O modules has been installed in the plant room’s main control panel. The Priva controller manages all plant and equipment including a biomass woodchip boiler; temperature and humidity levels in the swamp, roof and side vents plus sun blinds and local infra-red heaters.
“Temperature is maintained at 27°C but we also supplied an option for night setback of 25°C in order to conserve energy. Pond temperature is kept at 25°C with the swamp humidity between 75-80% RH,” explains Mr Grant. “The humidity system uses a high pressure pump and distribution system that forces water through very fine nozzles at 110 bar, at which point it atomises into very atmospheric fog. The infra-red heaters, complete with their own sensor, provide a controlled hot spot for the snakes.”
The sun blinds fitted to the roof and side of the swamp building are activated in accordance with pre-set light levels. As the temperature in the swamp rises, the roof vents open, followed by the side vents if necessary. If these actions are not sufficient to maintain temperature, the sun blinds are then closed. During the night, the role of the blinds is reversed and used as thermal energy screens: when the outside temperature drops below a preset value the Priva controller closes the blinds in order to keep the heat in.
Seeds of success
Continuing the unusual applications theme, sometimes it’s not even animals that are the prime non-human beneficiaries of BMS technology – vegetation is also feeling the warm glow of comfort that a BMS can provide. A project called Valcent Verti-Gro, again at Paignton Zoo, provides a good example. Verti-Gro is essentially a multi-storey chamber that acts as a way to grow vegetables and plants indoors, allowing a minimal use of water (only 5% of normal) and eliminating the need for herbicides and pesticides.
The technically interesting aspect of this project is that the Priva BMS is being used for three distinctly different areas of control: the greenhouse environment, irrigation and the conveyor system that rotates the hangers supporting trays of plants.
“The fact that one Priva HX8e controller can do all three things simultaneously demonstrates the flexibility of both the hardware and programming software,” says Mr Grant.
Another largely horticultural case study centres round the ABLE project, a widely-publicised social enterprise in West Yorkshire. The project, which reaches out to disadvantaged youths through sustainable food production, utilises control technology to manage the internal environment of two aquaponics (a combination of aquaculture and hydroponic plant production) greenhouses.
The ABLE project provides an outlet for ‘at risk’ young people; helping them to learn about healthy eating and horticulture as well as generating income from the sale of the food.
Housed within the greenhouse are fish tanks, hydroponic growing beds for plants, an air handling unit, an air source heat pump, and an aeration system. Duncan Grant of Ecotech quickly realised that the standard programming module base available in most BMS vendors’ engineering tools simply wouldn’t work here because every control module needed some level of customisation.
“This was a very much a bespoke project and Priva’s TC Select engineering tool provided the answer because its flexible nature means it is easy to adapt for unusual applications,” he says. “It contains a suite of hundreds of standard control modules to choose from, which allows us to customise a standard module, or even write a new module from scratch.”
Priva’s Compri HX4 controller manages the air source heat pump, while monitoring the greenhouses’ energy use closely; the air and water temperatures are taken every second. Readings of the temperature outside the greenhouses are also taken, and the heating or cooling adjusts automatically if the weather gets warmer or colder. This means that the systems environment is maintained and controlled at all times and, of course, no energy is wasted.
The outcome is another triumph for all involved: data such as fish fee
d given, number of fry introduced, number of fish harvested, plants planted and harvested can be entered on a daily basis and is then logged by Priva’s TC History. This allows some of the youngsters at ABLE to view these figures along with the greenhouse operational data and feel even more engaged with the project – thus giving additional value to this important social enterprise initiative.