When nature calls while out boating, the waste from the marine toilet – or head – flows through to an onboard holding tank. The potent contents of this tank then need to be responsibly disposed of at some point. There are likely pump-out stations at the marina, but there are also boats that can take away stored sewage. And the vessel recently delivered to Branford, Connecticut, is somewhat cleaner than most.

Where other pump-out boats run on dirty engines, Branford's 25 ft (7.6 m) aluminum craft has solar panels feeding battery banks to power the outboard motors and the sewage pump.

Reported to be the first of its kind, the solar-electric sewage pump-out boat is the result of a collaboration between East Shore District Health Department and Yale University's School of Public Health, with funding from the US Fish and Wildlife Service and the Connecticut Department of Energy and Environmental Protection.

Propulsion comes from two Torqeedo Cruise 4.0 outboard motors that get their juice from four Torqeedo Power 48 Li-ion battery banks. These batteries are recharged by eight 100-watt solar panels mounted on the roof canopy, which are said to provide 400 watts to each bank. The solar-electric system also powers the vessel's 48 V pump.

"Our research into current solar-electric technology for this vessel demonstrated that is a viable alternative to traditional internal combustion engines for recreational and commercial boats, and we hope the success of this project will lead to wider acceptance of this technology across the marine industry," said Michael Pascucilla of the East Shore District Health Department.

The solar-electric pump-out boat is being operated by non-profit Coastal Tide Marine Services under contract with the Town of Branford and the East Shore District Health Department.

The video below discusses the development of the vessel.

View gallery - 2 images