Go Solar Without Building a Solar System
The majority of oyster farmers in Maine who use solar power have homemade or partly do-it-yourself systems. While these existing systems are impressive, they require insider knowledge of how electrical systems work. Not to mention that building a solar system takes a lot of time that many growers just don’t have at their expense. To simplify the process for oyster growers to go solar without requiring in-depth technical knowledge, Nauti Sisters Sea Farm and Shred Electric partnered up to develop a prototype solar barge thanks to a USDA Northeast SARE grant provided to The Boat Yard, LLC.
The barge includes a variety of electric and solar powered systems with the goal of testing them out to see what works and what needs improvement. Plus, the Nauti Sisters Sea Farm crew is reducing their reliance on fossil fuels while benefiting from a quiet reliable and solar powered oyster farm.
What’s on the Nauti Sisters Solar Barge?
Catamaran Design and Flat Workspace
The solar barge is a flat workspace on top of a metal catamaran hull. The flat deck of the barge provides lots of working space and room for equipment. The catamaran hull provides a stable base for the work platform while still enabling the barge to motor through the water when necessary.
Solar Array and Battery System
Mounted onto a welded metal frame is the solar array that provides energy to all the systems on the barge. The six solar panels send electricity through a charge controller to a bank of marine grade batteries on the deck. The whole system can be monitored remotely from a mobile phone. All the electronic components of the solar array were installed by Shred Electric, a Maine-based marine electrification company that works with aquaculture farms to switch to electric gear.
With the Nauti Sisters solar barge, Shred is keeping tabs on how the system operates under working conditions out on the water. By treating the electric equipment without too much care, Shred is getting a good idea of what works well in the system, and what needs more work before other farms will be able to adopt it.
Tumbler and Washdown Pump
The gear that gets the most use on the solar barge are the tumbler and washdown pump. Both are powered with energy from the solar array and battery system. One of the major benefits of a solar powered tumbler is that it’s much quieter than one powered by a generator. Not only does this make the work more pleasant, but it helps prevent hearing damage from long days tumbling out on the water. Without the need for a generator running constantly, the Nauti Sisters crew can talk as they work, which makes the day in the life of an oyster farmer just a little more pleasant.
Electric Outboard Engine
Mounted off the stern of the barge is a fully electric outboard engine made by Torqeedo. The engine provides enough power to move the barge at about five knots, which is plenty for the purposes it’s designed for. For the time being, the motor is used to bring the barge to and from the boat launch at the beginning and end of the growing season. In the future, the motor will help move the barge to cages or floating bags of oysters so that the Nauti Sisters crew can harvest and process oysters at the same time.
Winch
Mounted to a small boom on the side of the barge is an electric winch that is critical to their operations. Nauti Sisters uses the winch in their harvesting process to lift cages/bags out of the water (see our other Innovations article on their “winch harvester!”). They hope that the lack of gunwales on the barge will make harvesting easier than with their other boats.
Finsulate Bottom Coating
Finsulate is a nontoxic alternative to bottom paint. Bottom paint helps prevent marine growth from building up on the underside of a boat. Traditional bottom paint slowly releases toxic materials into the water, such as copper, which is toxic to aquatic life at high concentrations. The Finsulate foul-release bottom wrap that is used on the Nauti Sisters Solar Barge prevents fouling build up using a dense fiber coating that’s attached to the boat’s hull. The coating lasts much longer than bottom paint usually does (Finsulate has a five year warranty) and can be cleaned with pressure washing instead of requiring the time consuming and expensive process of cleaning, sanding, and painting.
By testing out this coating on the solar barge, the Nauti Sisters crew is demonstrating that in addition to using solar energy, there are a multitude of other ways to increase the sustainability of the working waterfront.
The Future of Solar Powered Oystering
Running a solar powered oyster farm is quieter, more environmentally friendly, and better for air quality than using a gasoline generator. The crew of Nauti Sisters and Shred Electric put a lot of work into developing a barge design that could work for oyster growers across the state of Maine. After on-water testing and future improvements, the idea is that other growers could benefit from the quiet and environmentally sustainable solar barge system without having to go through the process of designing and testing one themselves. While this is the first year that Nauti Sisters is using this barge, it will be exciting to see what changes they make and where their design ends up next.
Innovations articles highlight creative devices or methods on aquaculture farms. They are informed by farm visits and interviews with experienced growers. See our About page for more information.