In 2015, United Nations Environmental Program released the publication, “District Energy in Cities: Unlocking the Full Potential of Energy Efficiency and Renewable Energy”. The report stated that:
- Cities account for over 70 percent of global energy use and 40 to 50 percent of greenhouse gas emissions worldwide.
- Half of cities’ energy consumption is for heating and cooling.
The above figures show that comfort cooling is a major consumer of electricity and is also responsible for a high percentage of greenhouse gas emissions in the urban environment. The same publication advocates for the adoption of district cooling as a sustainable energy solution for the modern city.
District cooling is the generation and distribution of cooling energy in the form of chilled water from a central chiller plant to multiple end-user buildings for the purpose of comfort cooling or process cooling. The chilled water produced at the central chiller plant is distributed to the consumers via a network of chilled water distribution piping.
District cooling systems achieve economy of scale by aggregating the cooling loads from a large user base into a central chiller plant. The large cooling demand seen by the district cooling system allows the adoption of energy-efficient technology such as industrial grade high-efficiency chillers, series-connected chiller modules, thermal energy storage, and cogeneration.
District cooling systems are often structured as energy utilities which provide cooling energy as a service. As a modern, cost-effective, and energy-efficient cooling energy solution, district cooling delivers numerous benefits to its multiple stakeholders.
Benefits to Building Tenants
- District Cooling ensures a more conducive building environment by eliminating noise pollution, vibration, odors/sanitary health risk associated with the in-building chiller plant.
- District Cooling enhanced building safety – omission of in-building chiller plant removes the safety risks associated with the operation of heavy machinery within the building.
- District Cooling service provider offers guarantees of high service reliability & availability (99.5-99.9%) for chilled water supply. A survey conducted by the International District Energy Association has found that District Cooling systems have a high reliability of 99.94%.
- District Cooling offers quality cooling energy. Assurance of consistent chilled water operating parameters ensure quality of comfort cooling.
- District Cooling offers 365 x 24 service.
- District Cooling also offers flexibility in meeting Tenant cooling demand at any time of the day, including after office hours and on Sundays and Public Holidays.
Benefits to Building Owners.
- District cooling lowers capital investment cost for Building Owners through the omission of capital investment cost associated with in-building chiller plant, related auxiliary equipment, and electrical infrastructure.
- District cooling improves the Return on Investment (ROI) for Building Owners, by lower capital investment which translates into higher returns.
- District Cooling improves Project Risk Management for Building Owners. The omission of the in-building chiller plant mitigates the inherent risk associated with the design, construction, operation, and maintenance of the chiller plant.
- District Cooling improves building services operational efficiency. Outsourcing of non-core chiller plant operations improve building services operational efficiency by eliminating operational issues associated with the in-building chiller plant.
- District Cooling reduces operation and maintenance expenses associated with the in-building chiller plant such as electricity, water, chemicals, spare parts, labor, repair, and maintenance work etc.
- District Cooling improves operational cash flow for Building Owners. Outsourcing the production of cooling energy eliminates the cash flow uncertainties associated with the operation and maintenance of the in-building chiller plant.
- District Cooling improves the security of comfort cooling. The district cooling service provider guarantees high availability of chilled water supply through the adoption of industrial grade equipment with built-in system redundancy. Advanced process automation control systems also help ensure the smooth continuous operation of the district cooling equipment.
- District Cooling reduces environmental impact through lower emissions. District cooling plant with thermal energy storage achieve higher energy utilization efficiency, thus reducing overall environmental emissions.
- District Cooling improves utilization of building space. The outsourcing of cooling energy production frees up building space and increases net leasable area, revenue, and income for the Building Owner.
- District cooling also lowers the building construction cost. The building structure design need not consider the additional load of the in-building chiller plant, cooling towers, water storage tanks, electrical equipment etc., resulting in a more economical design.
Economic Benefits to the Nation
- District Cooling, being an energy efficient technology, contributes to national energy utilization efficiency and helps to conserve valuable energy resources. Demand management strategy such as thermal energy storage shifts electrical power demand to off peak hours, allowing the more efficient base load power plant to be operated with higher generation efficiency and lower transmission losses.
- District Cooling reduces peak power demand and benefits power utility infrastructure. District cooling systems reduce peak power demand on power generation capacity of the national electricity grid through effective demand side management strategy such as thermal energy storage and/or cogeneration system. The demand reduction allows the national power grid to avoid additional investment in power generation capacity and transmission and distribution infrastructure.
- District Cooling contributes to conservation of the Environment. The technology’s system diversity and energy efficiency help reduce the emission of pollutants and greenhouse gases, lower the carbon footprint of the system, and lower the usage of refrigerant gases with global warming and ozone depletion potential.
- District cooling system improve energy utilization efficiency in generation of cooling energy which reduces emission of pollutants and greenhouse gases.
- District Cooling systems reduce Environmental Noise pollution. Elimination of in-building chiller plants leads to less noise and vibration associated with the operation of rotating machinery such as chillers, pumps, and cooling towers.
- System diversity allows district cooling plants to have lower installed plant capacity compared to individual building chiller plants thus effectively reducing carbon footprint and lower emission of refrigerant gases with global warming and ozone depletion potential.
- District Cooling enhances the aesthetics of the urban environment by omitting the unsightly chimneys and cooling towers at each consumer building.