Abstract
As a part of the Living Bridge Project on the Memorial Bridge between Portsmouth, NH and Kittery, ME a turbine deployment system for use at bridges was designed, built, and deployed. One of the purposes of the Living Bridge Project is to demonstrate that advantages to deploying hydrokinetic turbines at bridges exist. The expected advantages include 1) good hydrokinetic resources are likely to occur at bridges because bridges are typically built at constrictions where the flow tends to speed up, 2) existing bridge structures can be used as mooring points, 3) existing bridge permits can be leveraged to aid in the permitting of auxiliary hydrokinetic systems, and 4) power can easily be transmitted from a turbine to shore via the bridge. A tidal energy resource assessment was performed at the Memorial Bridge crossing the Piscataqua River in Great Bay Estuary in Southeastern New Hampshire. The purpose of the resource assessment was to quantify the kinetic energy that could be converted from the tidal currents to electrical energy, size a turbine for the location based on an estimated energy demand, and investigate potential energy management configurations. A turbine was selected for use at the site. The design loads for a turbine and a deployment platform were determined. Based on these design loads the turbine deployment platform and its moorings were analyzed. A 49 ft. by 18 ft. floating turbine deployment platform was designed. The turbine deployment system, which includes two vertical guide post mooring piles, a pontoon type turbine deployment platform, and the turbine pitching mechanism, was fabricated and deployed. A New Energy Corporation EVG-025H series tidal turbine with associated power electronics was deployed on the system in June of 2018.