On a chilly and rainy afternoon in May, Verdant Power staff and marine energy enthusiasts were buzzing with excitement after a successful retrieve-and-replace (R&R) operation of one of the three tidal turbines at Verdant Power’s Roosevelt Island Tidal Energy (RITE) Project on New York’s East River.

By providing tidal energy to the local utility grid, Verdant Power’s RITE Project exemplifies how tidal power can be incorporated into the existing power system. The R&R operation was intended to demonstrate Verdant Power’s new TriFrame™ mount, which was designed to ease operations and maintenance tasks for marine energy systems.  

Supported by the U.S. Department of Energy’s Water Power Technologies Office (WPTO), the RITE Project aims to demonstrate clean distributed energy to New York and how such technology could be used throughout the world. Tidal energy has the potential to enable U.S. communities—and others worldwide—to augment their energy resources with clean, renewable, marine energy. Advancing this technology will help reach the Biden administration’s target of a 100% clean energy economy with net-zero emissions in the United States by 2050.

Verdant Power TriFrame mount at its Roosevelt Island Tidal Energy site in New York’s East River

In May 2021, Verdant Power performed an R&R of one tidal turbine in their TriFrame™ mount at its Roosevelt Island Tidal Energy site in New York’s East River.

The fifth-generation (Gen5) tidal turbine that Verdant Power removed will be analyzed, and in its place sits a Gen5 turbine that boasts three new thermoplastic blades, designed, and manufactured by the National Renewable Energy Laboratory (NREL). In another six months, the NREL team will return to retrieve and assess this new material, which is expected to improve in-water performance and reduce costs. NREL will be analyzing the data collected during its six months of deployment in addition to investigating the durability of the turbine itself.

“This work will demonstrate a potentially game-changing material for marine applications at a meaningful scale as well as produce loads of data that we can use to validate design tools and de-risk future deployments in the industry as a whole,” said NREL Research Engineer Robynne Murray.

The goal of Verdant Power’s 2020 deployment at RITE was the testing of their TriFrame™ mount, which allows three large tidal power turbines to be deployed and retrieved simultaneously. The TriFrame™ mount was expected to save on construction costs and streamline maintenance overall by reducing on-water work, thus improving the viability of scaling up tidal energy.

After six months of continuous operation, Verdant Power found the TriFrame™ system achieved over 99% availability while generating 210 MWh—a U.S. marine energy record. Since October 2020, the tidal turbines have been providing clean energy to Con Edison’s distribution grid, powering homes and businesses in Manhattan.

NREL’s novel blade design is made of thermoplastic composites (materials you may find in your car door or engine cover), which in the lab have been shown to better withstand seawater environments as compared to traditional materials. The use of thermoplastic will prolong the life of the turbine blades and minimize waste due to their recyclability. Given the gravity of climate change, factoring in the longevity and future sustainability of renewable energy technology is as important as its immediate pollution-free power generation. 

“The utilization of more sustainable materials such as thermoplastics and the novel TriFrame™ design are significant technological steps forward for the marine energy industry, enabling us to collaboratively build a clean energy future,” said Jenn Garson, Acting Director of WPTO.

With broad recognition of climate change creating a rising demand for clean energy, the marine energy industry is growing rapidly and providing opportunities for Americans to get involved in the energy transition. The entire R&R operation took two days, with support from a professional crew. The project even caught the attention of local news reporters and Roosevelt Island community members, who took pride in the significant clean energy achievement happening in their backyard.

The successful R&R operation at Verdant Power’s TriFrame™-mounted RITE Project is an exciting milestone for Verdant Power and the marine energy industry. With the exchange process successfully completed, attention now turns to the six-month test of the new thermoplastic tidal turbine.

For more information on the RITE Project, visit https://www.verdantpower.com/rite.