District cooling and tri-generation will play an increasingly vital role in the storing and integration of intermittent renewable energy sources in the future, said an engineering consultancy expert.
“We are all aware that renewables are on the way to becoming the dominant source of energy. But because of the intermittent nature of renewables particularly solar and wind as a power source, the biggest challenge facing all of us is going to be energy storage,” remarked George Berbari, the chief executive of UAE-based DC Pro Engineering.
Interest in district cooling is increasing in Asia and the Middle East, especially in the Gulf region where its use has grown exponentially since the 1990s, he pointed out.
According to him, the United Nations Development Programme (UNEP) is taking an active role in promoting District Energy in cities via publications and financing studies and borrowing worldwide.
Berbari was giving his keynote address at the American Society for Heating, Refrigeration and Air Conditioning (ASHRAE) regional conference, titled ‘District Energy and Sustainable Development’ at Sharm El Sheikh in Egypt.
He told Ashrae, which boasts more than 55,000 members worldwide, that as renewables move towards becoming the dominant source for power in the decades ahead, the biggest challenge facing the industry is energy storage.
“If we are to allow for stored renewable electricity to be used for building heating and cooling that represents 60 per cent of the total buildings’ energy, the implications are that it will be costly, inefficient and require replacement every few years. There is also the cost of distributing it to the final user via the electricity grid, which will need upgrading in many cases,” explained Berbari.
However, the challenge presents a plethora of opportunities for District Energy as it provides the best technology to store and integrate intermittent renewable energy sources, with chilled or hot water stratified thermal storage tanks, that adopt district energy and tri-generation technologies, offering better value for money, greater operational efficiency and longevity than traditional power plants and storage facilities, he noted.
In addition, tri-generation offers the fastest response to grid stability and fluctuating production and consumption where a generator can kick in in less than 30 seconds, compared with a couple of days for nuclear or clean coal power plants and two hours for combined cycle power plant, he added.
According to Berbari, the countries in the GCC and wider Mena region expect all cooling capacities to double by 2030 with the majority of the increase expected to incorporate district cooling.
“This would signal an increase of cooling demand from about 5 million tonnes currently to more than 20 million tonnes by 2030. One example of the increase in demand is the new planned Cairo City district, which will require about 1 million tonnes in the next decade,” said the top expert.
It is crucial that city and municipal officers and residents of every city, town and village are educated on energy through awareness, stated Berbari, who is also author of ‘The Energy Budget’, which maps out a plan for sustainability and accountability for energy consumption in major towns and cities.
“Investing in district energy is just as important for towns and cities as investment in infrastructure such as public transport systems, because it promotes sustainability and reduces the number of industrial AC units, heat pumps and boilers,” he added.