Clean Energy 101: Renewably Powered Minigrids

The document defines renewably powered minigrids (or microgrids) as systems combining renewable energy sources, battery storage, and sometimes backup generators to provide power to communities or specific facilities. It details three configurations: isolated, undergrid, and interconnected. Case studies illustrate their use in the Caribbean for hurricane resilience, in Africa for expanding business and home energy access, and in the United States for reducing diesel reliance in remote areas and enhancing military facility resilience.

• Renewably powered minigrids are categorized into three primary configurations based on their relationship with the main electricity grid: isolated minigrids are stand-alone systems for rural areas without national infrastructure; undergrid minigrids use existing distribution networks but do not exchange power with the main grid; and interconnected minigrids are connected to the main system, allowing them to purchase energy to reduce battery costs.
• In the Caribbean, minigrids are deployed to maintain critical facility operations during extreme weather. Examples include a 390 kilowatt solar microgrid on Ragged Island in the Bahamas that meets 93 percent of the island's energy needs and 10 kilowatt solar microgrids with 76 kilowatt-hours of battery storage at two schools in Dominica.
• In Africa, minigrids improve energy reliability for homes and businesses. In Nigeria, the Zawaciki interconnected minigrid (1 MW solar, 1 MWh battery) increased power availability for some users from four hours a day to 16-20 hours. In Mokoloki, Nigeria, an undergrid minigrid with 100 kW solar PV and 194 kWh battery storage powers a health clinic, water purification, and various businesses.
• In the United States, minigrids are used for energy independence in remote regions and for military resilience. Kotzebue, Alaska, uses a system of 2 MW wind, 1 MW solar, and 1.2 MW battery storage to displace 350,000 to 400,000 gallons of diesel annually. Fort Hunter Liggett in California installed a 2.5 MW solar and 5 MWh battery minigrid in 2024 to provide 14 days of coverage during grid outages.

APA

RMI (2025). Clean Energy 101: Renewably Powered Minigrids. https://rmi.org/resources/clean-energy-101-renewably-powered-minigrids/

Chicago

RMI. Clean Energy 101: Renewably Powered Minigrids. 2025. https://rmi.org/resources/clean-energy-101-renewably-powered-minigrids/.

Wikipedia

{{cite report |author=RMI |title=Clean Energy 101: Renewably Powered Minigrids |date=11 December 2025 |url=https://rmi.org/resources/clean-energy-101-renewably-powered-minigrids/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{rmi2025clean, author = {{RMI}}, title = {{Clean Energy 101: Renewably Powered Minigrids}}, institution = {RMI}, year = {2025}, month = dec, url = {https://rmi.org/resources/clean-energy-101-renewably-powered-minigrids/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }