In the framework of the second International Exhibition on Energy Efficiency and Environment (Entech Hanoi 2010), the Hanoi Industry and Trade Department and the Hanoi Energy Conservation Center recently organized a seminar to discuss solutions for energy efficiency in buildings.

Actual situation and potential

The results of a survey carried out by the Ministry of Construction in coordination with the Hanoi Energy Conservation Center and the Ho Chi Minh Energy Conservation Center show that at the buildings where administrative offices are based, the amount of electricity consumed by air conditioners accounts for 75 percent of the total amount of energy consumption, and the remaining 25 percent is consumed by lifts, lighting equipment and office equipment. At other buildings such as trade centers, supermarkets and hotels, the amount of electricity consumed by air conditioners accounts for 60-70 percent of the total.

At 94 buildings that were surveyed in Hanoi, the amount of electricity consumed in 2008 totaled about 460 million kWh, an increase of 9.8 percent compared with 2007.

Generally, the use of energy in buildings remains wasteful and therefore the energy efficiency is still low. Multi-storey buildings (office buildings, hotels and apartment buildings) are the biggest energy consumers. The amount of energy consumption in the trade and service sectors accounts for 10 percent of the total amount of energy consumption in Vietnam and is forecasted to increase 3.6 times in the next 10 years due to the increasing occurrence of new trade centers.

Nguyen Cong Thinh, an official at the Department of Science, Technology and Environment of the Ministry of Construction, said, “In recent years, together with the growth of the entire economy, construction companies obtained an annual growth rate of 12-16 percent. Production was expanded and the use of energy as well as natural resources increased. Presently, energy consumption by the construction sector accounts for 20-24 percent of the total amount of energy consumption nationwide.”

Experts said that the potential for energy conservation in buildings, including both old and new buildings, is rather big.

For new buildings, appropriate design combined with the use of energy-efficient materials and equipment and qualified energy management officials can help save 30-40 percent of energy consumption. For buildings that are being in use or are to be improved, energy audits must be conducted so that appropriate energy conservation solutions can be taken to save 15-25 percent of energy consumption.

Effective solutions

Solutions for energy conservation in buildings not only help reduce the expenditure on energy use but also contribute to ensuring energy security, sustainable development and environmental protection.

To reduce energy consumption in buildings, it is necessary to take into account not only technical but also natural factors such as green space in order to utilize natural light and air. The simplest solution is to turn off electrical equipment when it is unnecessary to use them.

At the mentioned above seminar, experts and managers proposed many technical solutions for effective energy conservation in buildings. They all agreed with the opinion that it is necessary to build the energy consumption benchmark for office buildings, which serves as the basis to compare and assess the consumption of energy in buildings.

Sakamoto Yasuhiro from the Heat Pump and Thermal Storage Technology Center of Japan said that the technology of using heat pumps to save energy is being used widely and has shown its good effects in Japan. Heat pumps can be used to increase or reduce the temperature of thermal sources such as air, water, soil and rock.

Presently, the Vietnam Green Building Council (VGBC) is doing research to build the Lotus Energy System for use in energy management at three buildings: the office of the United Nations in Hanoi, the office and the factory of the Moc Bai Joint Stock Company in southern Vietnam.

Yannick Lillet, the executive director at VGBC, said that the Lotus Energy System will be built in accordance with internationally recognized standards that have been adjusted to suit actual conditions in Vietnam. This system allows companies to pay less on energy management. It is easy to use and meets international standards.

In 2008, the Ministry of Industry and Trade coordinated with the Ministry of Construction, the Hanoi People’s Committee and the Ho Chi Minh City People’s Committee to launch the Energy Efficient Building Competition. In the past three years, the competition attracted the participation of more than 100 buildings. Notably, five buildings of Vietnam have won regional awards at the ASEAN Energy Efficient Buildings Best Practices Competition. The organizing of such competitions is an effective way to encourage buildings to apply energy saving methods as well as to improve the community’s knowledge about energy efficiency and conservation.

By Tran Linh