DER, Solar

Benefits of Distributed Generation

Last week’s power outage in eastern North America focused attention on an archaic system of power distribution, highlighting present-day needs for more reliable local power sources.

Calgary, Canada – August 20, 2003 [SolarAccess.com] “This old, massive, centralized power distribution system does not fit in the modern world whose economic growth is increasingly centered on reliable power sources,” said Brent Harris, Director of Technology Development at Sustainable Energy Technologies. “Clearly distributed generation systems are more appropriate for present-day and future energy distribution needs.” Distributed Generation is defined as local or “retail” power – in direct contrast to the massive power operations which caused the power outages last Thursday. Distributed generation (DG), distributed resources (DR), distributed energy resources (DER) or dispersed power (DP) is the use of small-scale power generation technologies located close to the load being served. DG systems require a power generation device such as a fuel cell or solar electric modules and an inverter, the critical component that converts and delivers the power generated to the grid. The system has many benefits, including its flexible modular makeup, as well as significant advantages in energy efficiency, reliability, and power quality and emissions reductions. The following are a selected list of inherent benefits distributed generation offers over centralized power generation, according to Sustainable Energy: -In general, given reasonably reliable units, a large number of small units will have greater collective reliability than a small number of large units, thus favoring distributed resources. -Multiple small units are far less likely to fail simultaneously than a single large unit. -The consequences of failure are far smaller for a small than for a large unit. -Most distributed resources, especially renewables, tend not only to fail less than centralized plants, but also to be easier and faster to fix when they do fail. -Distributed resources tend to avoid the high voltages and currents and the complex delivery systems that are conducive to grid failures. -Appropriately designed distributed inverters can actively cancel or mitigate transients in real time at or near the customer level, improving grid stability. -Distributed resources can help reduce the reliability and capacity problems to which an aging or overstressed grid is liable. -Distributed generators can be designed to operate properly when islanded, giving local distribution systems and customers the ability to ride out major or widespread outages. -Distributed resources can improve utility system reliability by powering vital protective functions of the grid even if its own power supply fails. -Inverter-driven distributed resources can provide extremely fast ramping to follow sudden increases or decreases in load, improving system stability and component lifetimes. -Distributed resources can significantly-and when deployed on a large scale can comprehensively and profoundly-improve the resilience of electricity supply, thus reducing many kinds of social costs, risks, and anxieties, including military costs and vulnerabilities. -Distributed resources foster institutional structure that is more web like, learns faster, and is more adaptive, making the inevitable mistakes less likely, consequential, and lasting.