In places like Central America and Sub-Saharan Africa, Internet access, phone chargers and even clean water are hard to come by. WrightGrid and PV Pure -- two Boston-based start-ups -- are working to change that.

Guests:

- Ryan Wright, founder and CEO of WrightGrid, a start-up providing high-speed Internet and phone charging stations in remote locations. Follow WrightGrid on Twitter.

- Huda Elasaad, co-founder and chief scientist of PV Pure, a start-up creating on-site solar-powered water purification and grid systems for villages and small towns.

Both PV Pure and WrightGrid are part of Greentown Labs in Somerville -- the largest clean-tech start-up incubator in the United States.