Where can DE be used?

DE can be a practical solution anywhere thermal energy and power are needed. The suite of DE technologies is already being widely used all over the world in areas with and without a grid on a variety of scales. The figure below, taken from the WADE 2006 World Survey of Decentralized Energy, illustrates the extent to which DE is currently being employed in various countries.

Various different DE applicaitions are suited for both industrialized countries and emerging economies. Depending on the particular circumstances of the applications for which power and heating/cooling are required, particular DE technologies are better suited than others but often any range of options are possible.

In highly populated areas DE can complement existing central generation capacity and is useful in applications as diverse as:

  • Individual homes
  • Buildings:
    • Universities
    • Hotels
    • Supermarkets
    • Data Centres
    • Banks
  • Community Heating and Cooling
  • Heavy Industry
    • Petrochemical plants
    • Steel plants
    • Cement

In rural areas DE can also be very practical for a wide array of applications:

  • Water pumping
  • Rural electrification
  • Cottage industry
  • Textile mills
  • Sugar mills
  • Food products
  • Forestry

DE can also be an attractive economic option in a wide range of communities: from multibillion dollar high tech factories to remote and impoverished villages with little financial wealth and no modern energy. For example in a modern data center an array of high tech fuel cells may be an attractive investment to supply reliable and clean power on-site. In such applications, an electrical grid and fuel supply infrastructure (such as pipes for natural gas) are prerequisite. On the other side of the spectrum, in a remote village with no exisiting power grid or source of modern energy villagers may also invest in DE, for example in the form of a small wind turbine or PV panel to provide basic illumination or help charge mobile phones.

Term

Acronym

Notes

Decentralized Energy

DE

Electricity production at or near the point of use, irrespective of size, technology or fuel used - both off-grid and on-grid. DE includes high efficiency cogeneration (CHP), on-site renewable energy and industrial energy recycling and on-site power.

Renewables/ Renewable Energy

RE

Energy sources that are naturally replensihed in the short term, including non-carbon technologies such as solar energy, hydropower and wind as well as carbon-neutral technologies such as biomass. There is considerable overlap between renewables and DE. When renewables are used to generate power where it is required renewables can be said to fall within the DE definition. On the other hand large wind farms, that are built remotely from where the electricity is used, do not fall under the DE definition.

Distributed Generation

DG

Often used interchangeably with DE although sometimes DG refers to power only whereas DE includes thermal energy and electrical power.

Microgeneration


Very small scale applications of DE- usually at the scale of an individual home.

District Energy (District Heating/Cooling)

DE/DH/DC

Production of steam, hot water or chilled water, or a combination of the three, at a single central plant for distribution to other buildings through a network of pipes. The term is closely related to DE. It often, but not always, overlaps with DE. When district energy systems employ waste heat from electricity generation to supply heating/cooling networks they can be considered DE. In some cases, however, district energy plants are used in heat only applications in which case they are not considered DE.

Combined Heat and Power

CHP

The simultaneous production of both electricity and useful heat. CHP can be on any scale from very large applications in refineries to tiny machines in individual homes. CHP is one type of DE.

Cogeneration


Term used interchangeable with 'combined heat and power'. Cogeneration is the simultaneous production of both electricity and useful heat. Cogeneration can be on any scale from very large applications in refineries to tiny machines in individual homes.

Combined Cooling Heating and Power/Cooling Heating and Power

CCHP/
CHP

CCHP is the simultaneous production of electricity and useful heat and cooling (usually by a heat powered chiller). CCHP is one type of DE.

Trigeneration


Term used interchangeably with CCHP. Trigeneration is the simultaneous production of electricity and useful heat and cooling.

Uninterupted Power Supply

UPS

Term often used to describe on-site power, especially in the context of emergenecy power for computers. The term is usually associated with fossil-fired generators and implies power only applications, however it can also refer to applications where waste heat is recovered in which case greater environmental benefits would be realized.

Backup Generator


Usually associated with fossil-fired generators and implies power only applications, however it can also refer to applications where waste heat is recovered in which case greater environmental benefits would be realized. Renewable technologoiges are also increasingly being employed to provide backup power.

Captive Power


Term closely related to DE often used to describe on-site power. The term can imply either power only or cogeneration applications.

Embedded Generation


Closely related term often used to describe on-site power. The term can imply either power only or cogeneration applications.

Micro grid


A collection of DE technologies grouped together in a specific area and often connected at a single point to the larger grid.

Distributed Resource

DR

Often used interchangeably with 'Decentralized Energy' or 'Distributed Generation' but because a resource can also be either supply or demand side DR also includes conservation measures at the point of consumption.