A heat pump is at the heart of 'animazing' new low carbon £300,000 visitor attraction at Banham Zoo, providing a year-round subtropical environment and home for exotic species
NAMED 'EUREKA', the new 3,500m2 building presented a major challenge for the heating system design because not only does it need to welcome the Norfolk Zoo's 200,000 visitors per annum but also maintain a constant temperature of 20 degrees Celsius, allowing the wildlife inside to thrive, regardless of the great British weather.

It was essential that the new building incorporated the optimum low carbon heating and energy system, consistent with highest environmental credentials of the zoo. Plus a top priority was minimising heating costs, and the multi-layered combination of potentially conflicting factors created a demanding brief which was met by Dimplex installer partner Finn Geotherm.

'This project really did demand a 360-degree approach, careful thinking and an in-depth understanding of the way to combine different technologies for the ultimate integrated solution, because one size very definitely doesn't fit all,' says Guy Ransom, Finn Geotherm's commercial director.

Finn Geotherm's solution, which was named Energy Efficient Initiative of the Year at the 2013 Energy Efficiency & Renewables Awards, has already delivered a 15 per cent lower than forecast running cost.

It sited a high power 60kW Dimplex air source heat pump LA 60 TU at the heart of the system, providing high performance with a small footprint. The heat pump is linked to a 1,000 litre Akvaterm thermal store, with heat distributed via six separate temperature-controlled underfloor heating zones, so each can be controlled to suit the needs of the individual animals.

Additional system integration and control is via roof-beam mounted water/air heaters which provide a space heating boost as the building's doors are frequently opened and closed. In all, the Dimplex air source system delivers the constant required heat at approximately 60 per cent of the cost of a fossil fuel system and Banham Zoo's chief executive officer, Martin Goymour is delighted with the result.

'We're very proud of our latest attraction and the fact that we have achieved the best of all worlds for our zoo, with the controlled climate that really does provide greener energy and running costs that are so far even lower than forecast. So that's a great result and the added bonus is that it's of genuine interest for our visitors and school groups as well,' he says.

As an award-winning visitor attraction, the aesthetics of the heating and cooling system also needed to be taken into account, adds Ransom.

'Visitors are here to be amazed by the animals and although we're delighted that the green heating system has also proved a talking point, the installation has been able to disappear against the fantastic oasis. It is not obtrusive in sound or appearance and takes up the minimum amount of space too.'

Planning for the new building - a replacement for the zoo's original 1968 animal house - took three years, and since Easter 2013 it's provided the home for a diversity of animals including spiny-tailed Monitors, Swainson's lorikeets, white-faced Saki monkeys, Egyptian fruit bats as well as exotic plants.

The system was put to the test immediately as it was commissioned during the coldest spring for 50 years and wintery conditions but it still came up to target temperature in just two days. And within just weeks of the Eureka opening, the 15 per cent lower than anticipated running costs were indicating a seasonal performance factor (SPF) of 3.4.

Water for the plant irrigation system is provided mainly from the roof water collection tanks. Triple glazed translucent roofing sheets provide natural light and help retain the heat during the cooler months. And controlled roof venting system will give natural cooling, assisted by cooler air from louvred vents in both sides of the building.

And wintery conditions during the coldest spring for 50 years made sure the system's performance and integrity was put to the test straight away.