District heating

Figure 1. Underground tunnel containing district heating pipes in Denmark.[1]

District heating is the process of using a network of insulated pipes used to deliver hot water or steam from the point of generation to people in a district (end users).[2] District heating is often used for residential areas, industries and universities, which avoids the need to produce heat in individual homes, while still allowing for efficient transfer of this heat.

This heat can be provided directly from sources such as fossil fuel, solar energy and geothermal district heating plants, heat pumps using electricity, or fuel cells. It can also come as a by-product of electrical generation in a cogeneration plant.[2] Once the hot water or steam is produced in a plant, it can travel up to 30 km or further if there are multiple heat sources connected together.[2]

The Drake Landing solar project in Okotoks, AB, Canada is a district heating system that makes use of the Sun's radiant energy. It takes in heat via solar collectors year-round, stores most underground during the summer, then uses this heat during the cold winter months. 52 homes make use of this energy, and 97% of their space heating needs are supplied by it.[3] Visit the page here for more information.

Benefits

There are a few clear advantages of using district heating:[4]

  • Allows a broad range of energy sources including both fuels and primary energy flows to work together to provide heat, which increases reliability and efficiency
  • Helps to manage the supply and demand of heat, to avoid unnecessary production while still meeting needs
  • Ability to increase efficiency of a fuel when a cogeneration plant is used
  • Reduces labour and maintenance costs associated with individual systems
  • Introduces opportunities for renewable energy sources which would otherwise not be economic or practical

For Further Reading

References

  1. Wikimedia Commons [Online], Available: https://upload.wikimedia.org/wikipedia/commons/9/9f/Heatpipe_tunnel_copenhagen_2009.jpg
  2. 2.0 2.1 2.2 Association for Decentralized Energy. (August 26, 2015). What is District Heating? [Online], Available: http://www.theade.co.uk/what-is-district-heating_191.html
  3. Natural Resources Canada. (August 14, 2015). Drake Landing Solar Community [Online], Available: https://www.nrcan.gc.ca/media-room/backgrounders/2012/3299
  4. Association for Decentralized Energy. (August 26, 2015). Advantages and Benefits [Online], Available: http://www.theade.co.uk/advantages--benefits_192.html