As the earth grows hotter, cities are trying to stay cooler — and the solution so far has been to add more fossil-fuel burning air conditioners, and hasten global warming.
This conundrum is perhaps most evident in a patch of reclaimed land along the Dubai Creek called Business Bay, where summer temperatures regularly soar above 100 F.
Developers of the complex of 240 offices, hotels and other commercial properties, which has been going up since the early 2000s, abandoned the idea of each building having its own, self-contained AC system. They opted instead for district cooling — a network that shares refrigeration among numerous buildings. The Dubai system will be the world’s largest of its type, which is said to burn less than half of the energy of conventional systems while cutting costs and carbon emissions.
Empower, the Dubai-based company building the system, said this month that it added another 43 buildings to the network in the first half of the year. That makes the company — full name Emirates Central Cooling Systems Corp. — the world’s largest provider of district cooling services, with more than 100,000 customers in almost 1,100 buildings.
Empower’s district cooling systems are installed in many of the emirate’s major real estate developments, including the Dubai International Financial Centre, Palm Jumeirah, Dubai Healthcare City and the Dubai World Trade Centre Residences.
Global demand for air conditioning is set to triple over the next 30 years, the International Energy Agency predicted, with most need coming from energy-strapped developing countries. A regulatory framework for district cooling would control costs, save more than $1 trillion of energy worldwide by 2035 and slash emissions, according to recent research.
“In buildings around the world, heating and cooling account for 35% to 60% of total energy demand and, on average, produce nearly 40% of emissions,” says McKinsey. “Since building stock tends to turn over only every 30 to 50 years, getting it wrong will lock in emissions, and potential costs, for decades.”
A district energy system heats or cools buildings via a network of pipes carrying water through a neighborhood or an entire city. Systems can connect renewables, waste heat, thermal storage, power grids, thermal grids and heat pumps, cutting energy use by as much as half.
“Empower’s district cooling services are witnessing increasing demand from building owners and developers who are starting to eliminate conventional cooling systems, which are causing health and environmental problems,” says Ahmad Bin Shafar, CEO of Empower.
The systems are less carbon-intensive and can help developers hit carbon reduction goals, says the United Nations, whose District Energy in Cities Initiative has been adopted in 14 countries.
“Well-designed district energy systems don’t just lessen climate change. They also bring benefits across the sustainable development agenda — improving health by cutting air pollution, increasing access to affordable and clean energy, and creating green and decent jobs,” a U.N. report stated.
In Bosnia and Herzegovina, the city of Banja Luka updated its 35-year-old network with a district heating system fueled by wood chips. The city slashed its fossil fuel consumption, cut emissions while saving $1 million a year in fuel costs. The project was supported financially by the European Bank for Reconstruction and Development.
“Installing district energy systems in cities is a win-win solution for people and planet,” says U.N. Environment climate specialist Niklas Hagelberg. “In 2018, 15 new cities joined the UN Environment-coordinated initiative and committed to district energy actions.”
In Europe, companies like Danish consultants Ramboll Group are designing systems for sustainable infrastructure projects including Taarnby, a suburb of Copenhagen that includes Copenhagen airport. It was built using a central large-scale electric heat pump combined with ground source cooling and waste water to supply 60% of the total heat demand for large buildings, including the airport.
French energy giant Engie is building a cooling network for Singapore’s new Punggol Digital District, integrating existing smaller systems at Jurong Town Corporation and the Singapore Institute of Technology.
“We can centralize the district’s cooling needs to reduce its energy consumption and carbon footprint,” creating “a district that is sustainable, liveable and attractive to businesses and talents,” says David Tan, Assistant Chief Executive Officer of the Jurong Town Corporation development group.
Engie has committed $58 million to a Centre of Expertise for District Cooling in Singapore to help develop similar projects across the region. The company operates more than 320 low-carbon urban heating and cooling networks in 20 countries including Malaysia, the Philippines and New Zealand.
On the island of Curacao off the coast of Venezuela, the Zakito District Cooling deep seawater system consumes only 10% of the energy of air conditioning, reducing carbon emissions by 90% and eliminating harmful refrigerants.
“Zakito District Cooling is a no-brainer for us,” says Rolf Sprecher, managing director of CCR Investment, which owns the Curaçao Caribbean Resort, Zakito’s first customer. “Cooling amounts to about 70%-80% of our total energy consumption. The Zakito District Cooling system offers us the possibility to realize cooling at a lower, basically flat and predictable cost for a 15-year term.”
In Europe, where district systems are flourishing in Denmark, Germany, Britain, France, Sweden, Finland and Serbia, several barriers remain, including local policies and regulations set by governments, says Monika Kuusela, senior manager of public affairs at Finland’s Fortum Corporation, a publicly traded clean energy company with major installations in northern Europe.
The density of historic cities makes it hard but “not impossible” to retrofit them for large new systems, says Kuusela.
“Investors should be encouraged by the predictable and stable regulatory environment,” she said. “The introduction of new systems requires large upfront investments which should be recognized and rewarded in a fair manner.”
July’s scorching heatwave across Europe highlighted the need for district cooling systems in cities “where there is an absolute need to efficiently use resources and the concentration makes economic sense,” says André Loesekrug-Pietri, director of the Joint European Disruptive Initiative, Europe’s equivalent of the U.S. Defense Department’s Defense Advanced Research Projects Agency, or DARPA.
“It’s heavy infrastructure and it takes a lot of time, effort and money to install it,” he said. Governments should follow Germany and Denmark in encouraging investment by creating “the right tax incentives and a long-term contract which offers stability,” he said.
France and Britain have announced plans to boost the deployment of district systems through public-private partnerships, leading funds to invest in projects that enjoy long-term, stable returns in a period of historically low interest rates.
“District heating is a proven technology that is increasingly viewed as a smart solution to the challenges facing the European energy market,” says AMP Capital, an Australia-based global investment manager. “We have found certain assets in this sector that represent excellent investment opportunities.”