In the basement of the Welsh School of Architecture, Cardiff University, sits a £200,000 piece of lighting equipment known as the SkyDome.
Highly advanced software combined with 640 individual lamps mean the dome can exactly replicate outdoor lighting from any season anywhere in the world. The hemispherical machine measures eight metres in diameter.
It allows students and professionals to monitor the effects of both daylight and sunlight on buildings. If natural light sources are optimised energy bills can be drastically reduced.
Dylan Dixon, a Research Associate at the Welsh School of Architecture, said: “In terms of day lighting what you are trying to do is optimise your lighting design. If during daylight hours you can get the best out of your lighting you can minimise your energy costs.
“If you let in too much direct sunlight it can increase the temperature to an uncomfortable level, but this is obviously more of a problem in other countries!”
A simulation of a full day can be completed in just a few minutes. As well as optimising the use of natural light the machine can test the practicality of designs for new or updated buildings.
The machine can be used to avoid problems like those suffered by the so-called Walkie Talkie building in London. The 500ft skyscraper has caused problems by intensely reflecting sunlight onto the street below and even melted parts of a parked Jaguar.
Sunlight can cause other issues with buildings at specific times of the day. In one test on a model of a swimming pool sunlight was found to reflect off the water straight onto the lifeguard position.
Scale models are constructed and placed in the centre of the eight metre SkyDome on a rotating turntable. This takes into account the rotation of the earth during the day.
But Mr Dixon explained clear weather conditions do not always equate to brighter skies. “Because of the distribution of light you could have more light in some circumstances on a cloudy day,” he said.
This is because cloud cover distributes light almost uniformly across the sky. On a clear day you have a very different delivery of natural light.
“You get a very bright source of light around the sun area and also a bright area around the horizon. But the point of sky opposite the sun is almost a dark patch,” said Mr Dixon.
The highly specialised facility attracts a large variety of users other than the school’s budding architecture students. The Jaguar F1 team even paid a visit to solve a problem of glare reflecting from their car’s steering wheel
The SkyDome in Cardiff is one of only two in Britain. Its counterpart at University College London is only four metres in diameter, meaning the models used in Cardiff can be much bigger.
