With communities experiencing an increasing number of wildfires, hurricanes and other extreme weather events, a microgrid could improve resiliency. To reduce the impacts associated with these events, many federal, state and local governments have, or are considering, adopting policies and programs to increase community resilience, and reduce property damage and costs of reconstruction, as well as insurance claim and disaster assistance payouts.
Microgrids can involve many technologies and take on many forms depending on a community's or entity's underlying goals. A microgrid is a smaller version of the national electrical grid and can disconnect, or "island," from the larger network during power outages. It does so with a controller — a device that establishes where to send the distributed energy resources on the microgrid.
With a combination of software and hardware, such as switches, the controller directs the stored energy or other electricity generated on-site to the appropriate buildings. That way, during a larger grid outage, the system knows to kick on for critical loads, whether it be refrigeration in a house, or a hospital, police station or retirement facility.
Although logistics and financing can be complex, some housing developers are planning entire communities to be their own microgrid.
For instance, NAHB member Lennar is working with a startup software company and the local distribution utility in Tampa, Fla., for a 37-home subdivision that will feature solar photovoltaics (PV), battery storage, hardware and software to control the electricity that flows through the small community.
"Tampa Electric is optimistic about the potential of this microgrid technology for residential neighborhoods," said Karen Sparkman, vice president of customer experience for Tampa Electric. "It offers many advantages for environmental sustainability, reliability and affordability. We are pleased to join forces with our partners at Emera Technologies to offer our customers this innovative new energy solution."
Consider these opportunities and challenges for any potential microgrid:
- Continued power during outages. Microgrid controllers work to distribute energy locally where it's needed.
- Grid and community resiliency. The microgrid can be set up to power local emergency response structures, ensuring the health of community members who would be at risk during a lengthy outage.
- Greenhouse gas reduction. If powered by renewables, microgrids can help jurisdictions meet climate goals and reduce the need for gas-powered backup generators.
- Financing. Some investors are ready to take the leap, but microgrids can have large upfront costs.
- Local utility policies. Because microgrids require integration to the larger grid, how local/state governing entities and utilities handle compensation for selling power back can affect project financials greatly.
- Risks associated with newer technology. Many controller software companies are new to the market, and the associated workforce is still developing.
A comprehensive approach with careful planning to determine feasibility is necessary, because microgrid setups are still evolving and require the input of multiple stakeholder groups.
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