Grace Ashiru
Acumen’s Hardest-to-Reach (H2R) Catalyze initiative has made a $5 million equity investment in the Zambian subsidiary of off-grid solar company Sun King. It’s the first time Sun King has taken equity directly into one of its country-level businesses. The money will fund Sun King’s nationwide rollout in Zambia, and it’s meant to help the company attract local-currency loans from Zambian lenders, so it can grow beyond Acumen’s cheque.
Founded in 2007 by T. Patrick Walsh and Anish Thakkar, Sun King designs and distributes solar kits and appliances (lights, fans and televisions) to off-grid households and small businesses. Its range runs from basic kits for lighting and phone charging to multi-kilowatt inverter systems that can power large homes, businesses, schools and health centres. Customers buy on a loan repaid over 12 to 24 months, paying daily, weekly or monthly by mobile money from $0.26 a day. The company entered Zambia in 2021 as Greenlight Planet Zambia.
According to the World Bank, nearly half of Zambians still lack electricity, and rural access sits at 33%. The country also relies on hydropower for 80% of its electricity, and Acumen noted that severe droughts in recent years have cut hydropower output. Acumen expects the investment to help Sun King reach nearly 5.6 million people over five years, including up to 4.5 million Zambians who’d get electricity for the first time.
Sun King CFO Krishna Swaroop said the company has seen strong unmet demand for affordable solar in communities the grid hasn’t reached, and that Acumen’s money gives it the capital and confidence to keep rolling out across the country. Sandra Halilovic, head of H2R Catalyze, said Sun King’s track record in other markets gave Acumen confidence its model could scale quickly in Zambia, and that the deal was designed to pull in local-currency debt from Zambian institutions.
The raise follows bigger group-level rounds. Sun King raised $40 million in equity from Lightrock in 2025, and $260 million in a Series D in May 2022, led by General Atlantic’s climate vehicle BeyondNetZero. It lands in a tighter market: VC funding for solar fell 40% year on year to $1.5 billion in the first half of 2026
