Increasing 5° AC temperature can save 30% electricity: Study

A five degree temperature rise in the air conditions used in the country could save net electricity of around 7,770 megawatt hour (MWh) or 30.19% of the total consumption on the national grid, found a Institute of Planning and Development (IPD) study.

As per the research, when the ACs are used at 22 degrees temperature they consume 19,783 MWh or about 76.88% of the national grid while the total electricity generation capacity of the country is (including captive power) 25,700 MWh.

However, if the ACs are used at 27 degrees, they would burn about 46.68% of the national grid, the study found.

Md Redwanur Rahman, urban planner and development researcher and Professor Dr Adil Mohammed Khan, executive director of IPD, conducted the research.

The research findings were presented at a programme organised by Institute of Planning and Development (IPD) on Friday.

Professor Adil Mohammed Khan said, "The excessive temperature in urban areas is the main problem that is creating long-term environmental and socio-spatial impacts on city dwellers. In the last two decades, temperature in Dhaka has increased by almost 3 degrees."

As per the study, currently, about 28 lakh units of ACs are being used in the country of which 65% are used in Dhaka.

In 2021, about 6 lakh units of ACs were sold, and in 2022 (the last 9 months) about 4 lakh units of ACs were sold. From 2016-2022, about 27.5 lakh units of ACs were sold in the country. AC usage has increased by about 20% per year in the last six years, the study finds.

Industrial facilities in the country consume 28% of the electricity while commercial users consume 11% and households 56%.

The researchers assumed that if ACs in the country run at least 8 hours a day at 26 degrees temperature, they would use 13,260 MWh or 51.53% of the national grid. However, with a 21 degrees temperature, they would use more than 84.11% of the electricity.

They said if the temperature is increased by 4 degrees (22 to 26) temperature, we can save net electricity around 6,523 MWh or 25.35%.

Adil Mohammed Khan said, "The use of AC is increasing in Bangladesh, which is creating urban heatwaves and causing great damage to the environment. However, if there is effective city planning with building regulations and proper policies for the use of AC, the pressure on electricity could be reduced to a large extent."

It is not possible to save energy without introducing Energy Efficiency Ratio (EER) in our building construction act, he added.

Researcher Md Redwanur Rahman said, "Agricultural production could be disrupted due to temperature rise. Many countries, including India, Japan and the United States, have formulated policies to fix AC temperature at 25-26 degrees."

ACs in the USA alone emits 2% of the world's greenhouse gases. If we cannot take policies, one day we will also be a big part of the greenhouse emissions, he said.

Professor Dr Aktar Mahmood, adviser of IPD, opined that initiatives should be taken to reduce AC usage by exploring the psychological reasons behind the practice.

Professor Dr Ahmed Kamruzzaman Majumder, head of the Department of Environmental Sciences, Stamford University, said that ACs are consuming a large portion of the country's electricity while agriculture sector is facing continuous energy crisis.

Architect Shahriar Iqbal Raj, assistant professor of the Department of Architecture, North South University, said that there is ample opportunity for architects and construction professionals to work on the architectural design and building materials to reduce temperature in the city areas.

Due to the lack of regulations, the AC systems of 24 degrees temperature cannot be installed in the buildings, said Engineer Md Mamun Ferdous, chairman of MEP Design Studio. If this could be done, it would be possible to reduce the electricity demand of the buildings by 40%, he added.

Planner Ashraful Alam, project director of Detailed Area Plan (DAP), said, "The temperature in Dhaka is increasing and people are getting dependent on ACs. We have to plant more trees in open spaces."