- Distributed generation, distributed resources, and dispersed generation provide for decentralized generation of electricity. Electric power can be generated close to its point of use.
Conventional electric power generation takes place at central generating stations designed to produce electricity in the most efficient way. (A typical utility generating station.) Despite its universal success, this method of generation has a number of drawbacks. The traditional system requires extensive transmission and distribution apparatus that typically uses 6-7% of all electrical power transmitted. Only 40% of the calorific value of fossil fuel is converted into electrical energy; the remaining 60% is dispersed as heat. A large proportion of this waste heat is potentially useable but because of the central location of the generation it is impractical.
- There are advantages and disadvantages of using distributed generation and a well engineered system produces the best results.
Advantages in using distributed generation:
- Convenient local positioning avoids transmission and distribution losses
- Generation adjacent to loads allows convenient use of heat energy (combined heat and power [CHP])
- Convenient local positioning enables available sources of energy to be used, for example waste products or renewable resources may be easily utilized to supplement fossil fuels
- Convenient local positioning allows the use of available single or three phase generation
- An example of the use of local resources for distributed generation is using methane generated locally at a municipal facility to supplement natural gas. Both methane and natural gas can be used as fuel in an engine generator that can be connected to the utility system. In such a way it is possible to supply the grid. There is the capability for exchange of power.
- Disadvantages in using distributed generation:
- Conventional distribution systems need adequate protection in order to accommodate exchange of power
- Signaling for dispatch of resources becomes extremely complicated
- Connection and revenue contracts are difficult to establish
- Issues that arise from the use of distributed generation are:
- The use of "Net Power" in certain areas of the US
- IEEE 1547 standard, still under formulation
- Safety concerns with energy generated from multiple sources
- System protection under two way exchange of power
- Cogeneration utilizes heat that is rejected from the burning of fossil fuels.
- Renewable Energy is derived from sources other than fossil fuels and does not pollute the environment. Renewable energy harnesses nature and can come from the sun, from wind, from water, and from waves. Other sources of renewable energy are available from organic matter, sometimes called bioenergy. Examples of renewable energy sources are:
- Solar energy that can be converted to photovoltaic energy
- Solar energy that can be converted to mechanical energy
- Wind energy derived from the use of windmills
- Biomass Energy derived from degradation of organic matter
- Wave power from the oceans
- Hydro power from rivers and streams
- Each of these energy sources has unique characteristics and can play an important role in conservation and the reduction of pollutants. Most renewable energy sources can only be used on the power grid with the help of energy storage and power electronic support. Wood and rivers have been used as organic sources of power for generations. However, the expanded use of renewable energy is in the early stages of development and shows great potential.
- Issues associated with the provision of renewable energy are:
- Equipment costs
- The use of renewable energy resources depends upon local availability
- Variability of output owing to dependence upon natural resources
- System integration of a variety of resources with conventional base load generation
- The necessity for technical innovation required to engineer a reliable system
- Hydrogen as a facilitator for energy storage
- RGLSolutions is a system integrator. We can enable industrial and commercial entities along with utilities to benefit from the variety of energy sources available centrally and locally.
- Roger G. Lawrence Selected Publication:
Distributed Generation: The New Guy on the Block?
IEEE PCIC 2003; Houston, Texas September 2003.