Modern district energy systems combine district heating, district cooling with combined heat and power, thermal storage, heat pumps and/or decentralised energy. They are increasingly climate resilient and low carbon, allowing the:
It is time for a redefinition of District Energy. It is no longer exclusively about heat or surplus energy, the traditional drivers of district energy. It's about local production matched to local use – and not only at a building level, but also at the neighbourhood and city level. It's about sharing energy between buildings. And it's about resource efficient neighbourhoods and resilient cities. District energy is an approach to applying technologies to co-ordinate the production and supply of heat, cool, domestic hot water and power to optimise energy efficiency and local resource use.
Modern District Energy Systems (DES) will enable Frankfurt to achieve 100% renewable energy by 2050. Through DES, the city will improve energy efficiency, be able to switch from fossil fuels, use waste heat and provide balancing for variable renewable energy sources.
Accelerating the uptake of energy efficiency and renewable energy in the global energy mix is the single biggest contribution to keep global temperature rise under 2 degrees Celsius (°C) and to reap the multiple benefits of an inclusive green Economy.
In Dubai, air conditioning represents 70% of electricity consumption. This led the city to develop the world's largest district cooling network, which by 2030 will expand to meet 40% of the city's cooling demand. District cooling is halving Dubai's electricity use for cooling and also reducing its consumption of fresh water through use of treated sewage effluent.
Tokyo is maximizing energy efficiency in its district energy systems through the use of waste incineration, waste heat from buildings and metro stations, heat pumps connected to local water sources and solar thermal. Land- use planning and policies require developers of new areas to assess the new opportunities for cost-effective modern district energy to identify a cheaper next available sustainable heat or cooling option.
The City of Vancouver for the 2010 Winter Olympics, developed a publicly owned district heating utility that captures waste heat from sewage. The financial structuring of the project proved the commercial viability of district heating in Vancouver and has encouraged private sector development of district heating elsewhere in the city.
In China, pollution penalties play an important role in driving the modernization of district energy systems, which currently meet 30% of heat demand. Anshan's investment in a transmission line to integrate the city's isolated boilers and to capture surplus waste heat is projected to have three- year payback period due to the avoided penalties on pollution and to a 1.2 million ton reduction in annual coal use.
The decision tree developed as an outcome of this publication will guide cities through the various stages in district energy development and highlight tools and best practices that could be considered based on their local conditions. This section provides an outline of the decision tree and key areas of intervention and action that will be available in the online tool accompanying this publication. This section also outlines a policy and investment road map that comprises 10 key steps to accelerate the development, modernization and scale-up of district energy in cities.
Why district energy, what is the energy demand and what are the next-available technology costs for district energy deployment?
When should district energy be developed, and what are the catalysts that take district energy from vision to reality?
What steps need to be taken to begin development of a district energy strategy in the city?
How can the city foster and develop district energy? How can incentives, policy frameworks, business models and tariff structures best serve district energy in the city?
An estimated 400 million people are expected to move to India's urban centres by 2050, increasing cooling demand and putting strain on the power system. In Mumbai, an estimated 40% of the city's electricity demand for cooling. India is developing district cooling in Gujarat International Finance Tec- City (GIFT City) as a replicable demonstration project.