Renewable Energy/Energy Efficiency Coordinator, Department of Agricultural Resources
Mattapoisett’s Robert Field of Copper Beech Farm, with the assistance of Roger Williams University Professor Dale Leavitt, has designed and constructed a creative off-the-grid solar electric (photovoltaic or “PV”) project for aquaculture use. His invention pairs a barge containing PV panels and battery storage with a conventional floating upwelling system (FLUPSY), a device that aquaculturalists use to force feed nutrient rich water to infant shellfish.
The invention has come to Massachusetts at just the right time. As aquaculture continues to expand here in the Commonwealth, aquaculturalists using traditional land-tied technology have often found themselves competing for space with other commercial and recreational uses of littoral waters. This new and improved FLUPSY, now free from a shore-based energy source, allows siting of shellfish nurseries in more remote, less controversial areas.
The PV system consists of six, off-the-shelf 245 watt solar panels mounted on an angled wooden rack, an electrical distribution box, a charge controller that regulates the current from solar panels to the battery bank, nine 12-volt batteries in a wooden storage compartment, a 1/3 horsepower DC motor, a belt and a shaft and propeller. The two floats are pinned together to form a nearly square, articulating platform with its corners chained to mushroom anchors and oriented to face the southern sunlight. The battery bank is sized to operate for 3 days plus without recharge from the panels. To date, the system has performed better than expected, providing more than enough energy to operate the FLUPSY.
The project was funded in part by the Massachusetts Department of Agricultural Resources (MDAR) Ag-Energy Grant, an annual competitive funding program aimed at financing agricultural energy projects that improve energy efficiency and incorporate alternative clean energy technologies on Massachusetts farms. MDAR’s staff looks forward to working with Field to further promote this technology concept to the entire aquaculture industry.