Water Heaters, Neshw Only Works with Solar Hot Water. We’re Advocates for all Forms of Renewable Energy, But Solar Hot Water, or Solar Thermal, will Almost Always Yield the Best Payback and Return on Investment of any Renewable Technology. This Technology is Underserved in the New England Market, Primarily Due to the Attention that is Currently Paid to Solar Electric, But also Because the Skill Sets Required to Design and Install These System are not Yet Common; Collectors; Heaters; Panels; Design and installation of ...