A System that allows sunlight to be piped deep into the heart of any building without any heat gain from solar radiation while eliminating the need for electric lights during daytime, is said to have proved a tremendous success in Dubai.

''The SunPipe system was first launched at the Big 5 Show in Dubai in 1998 and since that time, 15 major projects have been completed with SunPipe applications. The SunPipe agent for the Middle East, Edison Lighting of Jebel Ali Free Zone (JAFZ) has a further 40 projects in the advanced planning stage, most of which are due to be carried out this year,'' says a spokesman for Monodraught Limited, its manufacturer.

Monodraught has 25 years experience in innovative daylighting and natural ventilation systems.

Consisting of a silverised mirror-finish aluminium tube, with a polycarbonate or acrylic dome at roof level and a clear polycarbonate diffuser at ceiling level, SunPipes are manufactured in 10 sizes from 200 mm to 1,500 mm diameter. Costs range from £200 ($284.18) per system for a typical flat roof application, says the spokesman.

''The added bonus, however, is that since the light pipe is sealed at the bottom with a recessed ceiling diffuser, a column of still air is created and since air is an excellent insulator against heat transfer, the SunPipes act like a giant double-glazed unit and totally eliminate any solar gain through the SunPipe as compared to conventional rooflights and skylights,'' he points out.

The spokesman continues: ''There is virtually no limit to the length of SunPipe that can be used or the number of bends that can be incorporated and indeed the SunPipe can even run horizontally. The remarkable effect is that a single 300 mm diameter SunPipe can light up to 25 sq m to a normal daylight level.

''Not only is there a considerable energy saving in eliminating the need for lighting during daylight hours but there is a further double bonus in energy saving since, firstly, the SunPipes eliminate the heat generated by the electrical lighting fittings themselves, thereby reducing the cooling load and, secondly, where SunPipes are used instead of rooflights, they also eliminate the heat generated by solar gain which also reduces the required cooling load.''

Sunpipes are ideally suited to any underground buildings such as military establishments and government buildings, which are usually totally devoid of any natural daylight and are, therefore, proving particularly popular in the UAE and the rest of the Middle East, the spokesman says.

''SunPipes are particularly favoured for schools, offices, villas and palaces and the larger systems offer considerably energy-saving potential for warehouses, factories and shopping malls.

''Monodraught also produces a special vandal-resistant high-security system, for locations that are considered vulnerable and therefore are much better than conventional rooflights because of their much smaller size,'' he adds.

Monodraught now has SunPipe distributors in 25 countries throughout the world.

''Such is the cost of SunPipe systems that pay back has been calculated to be between three and five years, according to the installation. All SunPipe systems carry a 25-year guarantee,'' the spokesman concludes.