Solar sewage pump out boat has only 1 tank to fill :)

OK, that headline is the only joke we will make. This is actually serious news. The town of Branford, Connecticut is the proud owner of the world’s first solar powered pump out boat. What’s a pump out boat?

Some background: As disgusting and selfish as it sounds (and is), there are some boaters who simply dump the sewage from their boats directly into whatever waterway they happen to be in.Of course, there are many marinas where they can have the sewage pumped from their boats and disposed of hygienically, but apparently some people feel that is too inconvenient.

Hence the development of the pump out boat, which actually comes to the owner’s boat and pumps the sewage from the holding tank into a larger holding tank on the pump out, which then disposes of the effluent correctly on shore.

What does this have to do with the town of Branford?

Shellfishing is serious business in Branford, and indeed all along the Connecticut coast. It’s not only a commercial enterprise, but clamdigging and shelfishing are also common enough recreational activities that the town has a page outlining the fees for permits (residents  $5.00, non-resident $10, seniors no charge in case you’re wondering).

We’ll give you a second to think of what effect the dumping of raw sewage might have on shellfish and oyster beds.

It is obviously in Branford’s best interests to make it easy for boaters to be hygienic. But…oil and gas pump out boats come to the beds with their own gasoline and oil problems.

So the East Shore District Health Department teamed up with nearby Yale University’s School of Public Health to see how all of the problems could be addressed. Funding was provided by a grant from the U.S. Fish and Wildlife Service and Connecticut Department of Energy and Environmental Protection under the Federal Clean Vessel Act. There was also some local fundraising efforts.

The result was the solar pump out boat.

It may not be as glamourous a use of solar power as the solar super-yacht we wrote about (below), but in a way it is a perfect application for solar-electric marine propulsion.

The pump out boats don’t need a big range or huge motors. They can use solar power, but since they necessarily have to go back to shore on a regular basis, they can also charge from the grid if necessary.

an electric outboard motor

Branford’s world first has two Torqeedo Cruise 4.0 outboards (comparable to 8hp gas burners) powered by four 48 V Li-ion batteries. The batteries are recharged by eight 100-watt solar panels, providing 400 watts to each of the two battery banks. The solar panels perform double duty as an awning to keep the operator cool. The batteries also drive the boat’s 48 V 1.5 kW pump.

As crazy as it sounds, this use of solar-electric power for boats is most likely great publicity for those of us who would like to see more electric marine propulsion. It’s the kind of thing that is juvenile enough to be remembered and talked about even by non-boaters. There may even be a market for them.

We’ll let Torqeedo US President Steve Trkla have the last word:
This new solar-electric vessel will set the standard for future pump-out boats in coastal communities worldwide. It’s a clean, green zero-fuel, zero-emission solution with long life, low maintenance and minimal operating costs.

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a luxury 64' yacht seen from above with solar panels on its roof

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