Residential Solar – The Basics of Distributed Power Generation
What’s distributed power generation?
Distributed power generation means that power sources are widely distributed, so that power is generated close to the place where it’s being used. The current system in the U.S. uses mostly “central generation,” where large plants pump out 500-3000 megawatts of power and then send it long distances. Distributed generation, as in the case of residential solar panels, happens at a much smaller scale (from about 1 kilowatt to 5 megawatts) and may travel only as far as the distance from the solar panel on your roof to your own home below.
What are the benefits of distributed power generation?
- It can make the whole grid more secure because there’s less reliance on any particular part of the system. With several smaller sources of power, if something goes wrong, it’s easier for another source of power to step in and fill the gap.
- It can help meet peak power needs. Solar power, for example, just happens to generate the most power on sunny summer days, the time when there’s the most demand for air conditioning.
- It can help reduce the number of transmission and distribution lines that need to be upgraded or built.
- It works well with renewable energy technologies like solar and wind power, which have environmental benefits.
Distributed power generation technologies
- Solar photovoltaics (PV): Solar panels are growing rapidly as a source of distributed power generation. If the solar panels on your roof are tied to the grid (as most solar systems are) then your own home can be providing power to others when your solar panels generate excess electricity.
- Wind turbines: Wind systems can be another good source of distributed power. These make the most sense in areas that are particularly windy, not surprisingly. They’re not good for dense urban or suburban areas, because of safety, issues with obstructions, and aesthetic requirements.
- Fuel cells: Fuel cells create electricity through a chemical reaction in a fuel. For utilities, most fuel cells currently use natural gas, which is not renewable. Research on fuel cells that use hydrogen or biofuels is developing quickly.
- Microturbines: These small turbines (about the size of refrigerators) make both electricity and heat in small amounts. They can run on nonrenewable fuels like natural gas, but can also use waste fuels.
- Internal combustion engines: Electric generators using internal combustion engines have a long history of providing back-up power. They typically run on non-renewable fuels like natural gas or diesel, although they can also use biofuels.
What’s next?
Distributed generation will increase in the future as the different technologies continue to become more affordable. The infrastructure for distributed power generation is also improving. The government has encouraged the growth of smart grid technologies, which support distributed generation, through policies and funding (including the Recovery Act, which set aside $11 billion for a national smart grid).
