Cooling the cities of tomorrow in South-east Asia - A shift towards carbon neutrality

THE COP26 summit produced a mixed bag of outcomes, with broad commitments by most governments on action to address the climate crisis. Turning such top-level pledges into sector-specific actions that can be taken now is a more challenging task. One energy-hungry feature of life today is the unrelenting pace of urbanisation, which brings with it an ever-increasing demand for electricity.

More than 50 per cent of the world's population now lives in urban areas, compared to only 29 per cent in 1950. In Asean, it is estimated that by 2050, almost 70 per cent of the population will be living in cities. Such massive population density results in what is termed the "urban heat island" effect. Recent research has confirmed this effect throughout Asia in big cities such as Bangkok and Jakarta. Its effect occurs when buildings shed heat in order to cool themselves, which means neighbouring buildings themselves need more energy to keep cool. The rising urbanisation in Asia is leading to an increase in the size of urban heat islands, as well as their number. In some cities, the night-time temperature can be as much as 6 degrees Celsius higher than the surrounding suburbs and rural areas.

Not only are urban population numbers growing, increasing lifestyle expectations mean a greater consumption of energy. In South-east Asia, rising electricity demand from cooling alone is projected to require around 200 GW of additional generation capacity in 2040, and cooling could be responsible for as much as a 30 per cent share in the region's peak electricity demand.As COP26 made clear, South-east Asia, like the rest of the world, is also facing the effects of major climate change. According to a study by McKinsey, by 2050, between 600 million and 1 billion people in Asia will be living in areas with a non-zero annual probability of lethal heat waves.

While great strides are being made in the development and deployment of renewable energy solutions that will help mitigate the causes of climate change, it is also clear that for business and social life to continue with an acceptable level of comfort, we need to find and apply the most effective and efficient methods of cooling our cities.

Traditionally, buildings - whether residential, office blocks, schools, shopping malls, et cetera - have used a variety of air-conditioning systems, from window-mounted units to central systems using ducts in larger buildings. The efficiency of these systems depends on several factors, including their power and the ability to ensure the even distribution of cooled air through the building. The biggest drawback of conventional air conditioning systems is that they are all stand-alone, cooling only the building - or even just the room - in which they are installed.

The growing demand for cooling in stressed urban environments has led to the increasing popularity in recent years of efficient district cooling systems (DCSs) that feature a centralised cooling plant serving a group of buildings. DCS owes the rise in its popularity to its proven ability to be as much as 30 per cent more efficient than traditional, decentralised air-conditioning units. Encouraging the growth of large-scale district energy systems has the potential to reduce the electricity demands in areas where cooling represents more than half of the power consumption. A DCS allows the centralised production of air-conditioning for an entire urban area, cutting energy consumption and CO2 emissions by 30 per cent. DCSs also remove the heat island effect.

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RELIABLE, SUSTAINABLE, COST-EFFECTIVE AIR-CONDITIONING

There are multiple advantages of a DCS, particularly when implemented as an integral part of a smart business district, such as the Punggol Digital District (PDD). The PDD is an example of Singapore taking the lead to optimise land use by building a smart business district that integrates businesses, schools and the community. The integral DCS will provide air-conditioning in a reliable, sustainable and cost-effective way to the business park, community, retail outlets, and transportation nodes within the district. The plant will have a cooling capacity of close to 30,000 refrigeration-tons, equivalent to cooling 8,000 4-room Housing Board flats.

Leveraging the technology of the Open Digital Platform at PDD allows the integration of various systems across the district, including the DCS. This helps to track energy consumption patterns, to optimise energy distribution and provides cost efficiency across an entire district. PDD is the first in Singapore to adopt a single integrated master plan approach that brings together a business park, a university and community facilities.

Singapore is not alone in its need to address the effects of global warming. As Asean Cooperation on Environment has highlighted, South-east Asia is one of the most at-risk regions in the world to the impacts on climate change.

Other major regional cities are also using DCSs to provide urban developments with efficient air-conditioning that also reduces electricity and water consumption as well as CO2 emissions. In Malaysia, Megajana provides district cooling services to buildings in Cyberjaya. The system reduces energy consumption, lowers operating costs of buildings and ensures environmental sustainability which supports the idea of making Cyberjaya a green city.

In the Philippines, the industrial park of Northgate Alabang, near Manila, has been converted into a green district. Its associated DCS plant was successfully commissioned in July 2017 and is providing cooling to 12 existing buildings with 4 new buildings planned, to optimise energy supply, reduce electricity consumption, support economic development and lower environmental impact.

The challenge is to deal with an increase in urban population and expectations for quality of life, while taking the necessary steps to combat the effects of climate change. By allowing the efficient use of resources, we will be able to welcome more people in the city of tomorrow. And with solutions like DCSs we will eliminate the heat island effect, with the very real outcome of making it possible to enjoy life outdoors by maintaining a reasonable ambient temperature.

Increasingly, DCSs will play an essential role in helping South-east Asia meet its cooling needs while achieving its sustainability goals, as the region makes the shift to carbon neutrality.

• The writer is CEO, Energy Solutions Apac, and Country Head South-east Asia, Engie Group.