Nearly 1 billion people globally2 are served by health care facilities that do not have regular or consistent power. Unreliable energy disrupts routine and emergency care—from running diagnostic tests to ensuring vaccines stay cold. As heatwaves, floods, and other extreme weather events become more common, energy disruptions are expected to increase due to events like power outages and heat stress on existing infrastructure. To address these challenges in the last mile of polio eradication and reduce its carbon footprint, the GPEI and partners have turned to solar power, a more affordable, reliable and climate-resilient energy source to power polio vaccination and surveillance activities.