One of the concerns with wind and tidal energy installations is that the turbine blades are built from materials that are not easily recyclable. As the blades wear out with use, they could create a significant disposal problem. For the last several years, the US Department of Energy’s National Renewable Energy Laboratory (NREL) has been developing new designs for turbine blades that could be more easily recycled and may prove more durable in high-energy environments like tidal streams.
NREL is now partnering with Verdant Power, whose tidal turbines are currently deployed in New York City’s East River, to test the new thermoplastic blade design. Unlike the current epoxy-infused composite thermoset blades, the thermoplastic blades can be melted down and recycled. The thermoplastic blades may also be better suited for use in tidal currents. The current testing should provide real-world data to determine if the new design is more rugged than the current blades.
Since 2006, Verdant Power has been working to install tidal turbines on the bottom of New York’s East River off Roosevelt Island. Things have not gone entirely smoothly. The turbine blades on their early designs had a tendency to fail in the strong tidal stream. They were not alone in their problems. OpenHydro’s tidal rotors in the Bay of Fundy also had a tendency to come apart.
The latest generation of the Verdant design is a modular TriFrame mount, which holds three tidal turbines. The turbine blades are an epoxy thermoset design. (We recently posted about the 2-megawatt O2 turbine installed off Scotland, described as the most powerful grid-connected tidal turbine in the world, that also uses a similar design of epoxy thermoset blades.)
In the first six months of testing of the new Verdant turbine installation, they successfully generated almost 200 megawatt-hours of energy — a U.S. record for marine energy production. In May, Verdant swapped out one of the epoxy-bladed rotors with a new, NREL-manufactured rotor with thermoplastic blades that are identical to the original epoxy blades except for their material.
In addition to the new rotor, an NREL-built data acquisition system is installed inside the tail cone of the newly installed tidal turbine, allowing researchers to measure the strain and angular position of the thermoplastic blades while in action in the East River.
NREL’s Thermoplastic Blade Research Dives Deep With Verdant Power’s Tidal Energy Turbines
Now for the onset of the worriers. Fouled fishing gear. Blades that shed plastic to be ingested by wildlife. Blades will destroy fish like a blender. You get the idea. Nature conservancies of america will find some reason why these things should not be erected.
Not in the East River. No fishing there if you like living. Any wildlife, if there is any, in the East River is not anything you want to be around anyway. Even the Fulton Street Fish Market moved.
Back in the 1960s our rivers were so polluted that there were no fish and little need to antifoul boat bottoms to prevent weed growth. Also, when the wind was from the south we got covered in dust from the cement works chimneys and if it turned to the North we got coal dust from the power station covering everything.
Now we have fish and seals and dolphins/porpoises and of course weed and barnacles on the boat hull. I can live with that.
We just need the farmers to stop using phosphates and for the water company to stop releasing raw sewage during heavy rainfall. Oh, and for the trawlermen to stay out of the river and let the fish grow.
Pardon my foopah. I was speaking in general of what would happen if it were to be tried elsewhere.
Locals here is Maine seem to think these things would act like macerators and chew all things living. Regardless of what science can prove.
Hmm, I wonder if those bladeless cooling fan gadgets could be made to work backwards? Or would they just get blocked up with shellfish like power station cooling water outlets?