MassHousing announced that it has closed on $25.9 million in affordable housing financing to WinnCompanies for the redevelopment of historic Stone Mill in Lawrence into 86 units of new, highly efficient rental housing. The 177-year-old Stone Mill property will become the state’s first all-electric housing development and is being built with energy efficiency measures that will lower the building’s carbon footprint. The property, located steps from the city’s transit center, will serve residents across a range of incomes.