Energy saving and renewable energy technologies featured heavily in the recent Northern Ireland Sustainable Planning Awards organised by the RTPI and RSPB, won by the Orchard Building at Stranmillis College.

Claire Ferry, RSPB, explains “We were looking for great examples of sustainable building in Northern Ireland, incorporating community consultation, recycling, careful water use, support for wildlife and of course energy saving and renewable energy devices.

“The range of applications was so wide it was difficult to compare the very different schemes, but we were pleased to see that all developments gave consideration to reducing carbon emissions.”

For the Orchard Building, energy use was an important consideration, as educational buildings traditionally have a high energy use – and therefore high running costs. By assessing the lifecycle of the building, it was shown that a biomass boiler using wood pellets would pay back over 11 years, easily within the lifespan of the building. The heating system is underfloor throughout, which has practical as well as energy saving benefits. For example, there are no wall radiators needed in the sports hall, which leads to a better and safer use of the space.

Alongside the biomass boiler, the architects employed design techniques to achieve good natural lighting within the building. The teaching wings are accessed from a main, naturally lit central atrium. Teaching spaces are designed to achieve natural lighting through large double-glazed windows, argon-filled and using low-emissivity glass. External wooden louvres shade lower windows, while light shelves inside the room reflect daylight deeper into the room. Sun pipes, essentially hollow tubes extending down from the roof, also bring natural light into the central corridors and into the rear of the rooms. 

In the sports hall, translucent glass blocks are used to provide natural light with no glare, and at the same time improve heat retention. All other lights are low energy and responsive to daylight levels, with movement detectors where natural lighting is not possible.

The College has an existing building control monitoring system whereby existing heating and power usage can be monitored and assessed from the College engineers’ office. This system has already allowed the building to be heated and used from 9am to 5pm for the same cost as was previously required for use for just four hours.

The judges were particularly impressed by the efforts to ‘future-proof’ the building – to make sure that technologies currently too expensive or poorly developed could be included at a later date. Examples include solar heating and photovoltaic cells as well as ground source heat pumps. Cabling has been installed so that the College can install those technologies when the price and payback times have improved. In fact, the first solar heating panel is already being tested.

Hill House, a private dwelling in County Down, was commended as runner-up. Energy saving measures were built in at the design stage to exceed the Building Regulations requirements. The main house was designed with thick masonry to absorb and retain heat, keeping the house warm in winter and cool in summer. The main windows face south, both for the view and to allow passive solar heating, with only the occasional, small window facing north. All buildings have underfloor and roof insulation.

The games room is oriented due south and its roof pitch chosen to optimise the performance of the photovoltaic panels on the roof. The panels were sandwiched between glass and installed in a corrugated metal roof allowing light to penetrate into the room, while the cells provide protection from overheating and cast intricate shadows inside.

The house has solar water heating and this has reduced water heating bills even in winter.  There is a traditional fireplace for burning wood in the house and a small wood burning stove in the studio. A 50% grant was obtained under the now closed ‘Clear Skies Renewable energy Grants Programme’ for the photovoltaic panels and extra electricity generated by the panels is sold back to NIE.  The more recent installation of solar water panels was supported under an Action Renewables initiative. 

The other runner-up, the Connswater Community Greenway, is a sustainable development project on an altogether bigger scale!  The project team wanted to set construction quality at the start – specifications include reducing concrete use to lower carbon emissions and use of local materials and suppliers. One drawback was that renewable energy technologies to supply outdoor street lighting are not sufficiently developed and would actually result in a greater carbon load that grid electricity. Instead the project will source electricity through NIE’s green tariff.  The team will continue to keep energy saving in mind as the project continues – construction is due to commence towards the end of 2009.

Terry Waugh, Action Renewables and member of the award judging panel, was delighted by the efforts made by all finalists “It’s great to see people using renewable energy and energy saving measures even in something as simple as a new house, never mind large scale public buildings and urban regeneration schemes. It shows that everyone can make a difference, no matter how small."