DER - Distributed Energy Resources
The IEEE 1547™ Interconnection series of Standards defines a DER :-
“ a source of electric power that is not directly connected to a bulk power system (BPS). DER includes both generators and energy storage technologies capable of exporting active power to an electric power system ”
A DER is a ( smaller-scale ) electrical energy system that usually includes generation and increasingly storage - and that operates locally and is connected to a larger power grid at the distribution level.
DER allow an alternative paradigm of generating electricity (and heat) at or close to the point of demand. DER can includes fossil technologies—fuel cells, microturbines, and even diesel gen-sets. Mostly thought DER is harnesses renewable technologies ( PV and wind turbines ); energy storage options; and energy efficiency to provide low-carbon / low-cost energy.
" Potential DE advantages include higher efficiency and lower cost through waste heat recovery and avoidance of transmission and distribution, reduced global and local air pollutants, enhanced flexibility of electricity grids, reduced investment uncertainty through modular increments of new capacity, and greater system and infrastructure reliability and security " Neil D. Strachan
Environmental Impacts of Distributed Generation
Quote from the US EPA - Distributed generation can benefit the environment if its use reduces the amount of electricity that must be generated at centralized power plants, in turn can reduce the environmental impacts of centralized generation. Specifically:
- Existing cost-effective distributed generation technologies can be used to generate electricity at homes and businesses using renewable energy resources such as solar and wind.
- Distributed generation can harness energy that might otherwise be wasted—for example, through a combined heat and power system.
- By using local energy sources, distributed generation reduces or eliminates the “line loss” (wasted energy) that happens during transmission and distribution in the electricity delivery system.
However, distributed generation can also lead to negative environmental impacts:
- Distributed generation systems require a “footprint” (they take up space), and because they are located closer to the end-user, some distributed generation systems might be unpleasant to the eye or cause land-use concerns.
- Distributed generation technologies that involve combustion—particularly burning fossil fuels—can produce many of the same types of impacts as larger fossil-fuel-fired power plants, such as air pollution. These impacts may be smaller in scale than the impacts from a large power plant, but may also be closer to populated areas.
- Some distributed generation technologies, such as waste incineration, biomass combustion, and combined heat and power, may require water for steam generation or cooling.
- Distributed generation systems that use combustion may be less efficient than centralized power plants due to efficiencies of scale.
Distributed energy technologies may cause some negative environmental issues at the end of their useful life when they are replaced or removed.