Poorly designed urban buildings, especially those in developing countries, consume 50 per cent more energy than that used by transport and industrial sectors combined, experts at the UN-Habitat say.

The same buildings also account for about 38 per cent of green house gas emission.

"The amount of  energy used in  urban buildings for cooling, heating and lighting is more when compared  to the energy used in the industries and  transport sectors combined. This creates unnecessary demand for electricity that pushes up the price per unit,” said Dr Vincent Kitio, of the urban energy unit at the UN- Habitat.

Such buildings are not aligned with the climate and weather patterns of the area they are erected in. "We are talking about commercial buildings minus considering the direction of the sun light, the type of raw materials used and the occupant’s behaviors. 

"Our analysis indicated that commercial buildings would save up to 30 per cent on energy consumed if proper planning and designed was emphasised,” Kitio said in an interview.

Architects say most developers copy designs from the developed countries without considering climatic and geographical differences. "As result, a lot of energy is being wasted because of the unnecessarily demands such as cooling systems, external heating systems and indoor confirm lighting—things that are actually not needed,” said Prof. Federico Butera said. According to Butera, growing demand for energy is pushing up the cost of energy and this affects the general performance of the economy.

"This is ultimately stretching government’s capacity to provide enough energy to all sectors of the economy.” Butera said that stakeholders should pursue a green approach to attain economic transformation through development of green cities and villages.

Lillian Mupende, director general Kigali One Stop Centre said that efforts are on-going to sensitise all stakeholders on construction projects that are environmentally friendly and cost effective in terms of energy consumption.

"The City of Kigali is encouraging all real estate developers to integrate energy efficiency measures,” Mupende said.