Renewable energy is a bit of a new phenomenon, but it is all around us, even in places that you would not imagine. For example, in the East River in New York City, there is a project being carried out by hydropower company Verdant Power to install tidal power turbines.
The Roosevelt Island Tidal Energy (RITE) Project is located in the East Channel of the East River, where Verdant Power is currently establishing a system of underwater turbines, not unlike those used for wind power, that will generate enough electricity to power 75,000 homes. These turbines operate in a manner that Verdant calls “kinetic hydropower”, in that it makes use of IEC/TS 62600-200 ED. 1.0 EN:2013 to convert the current flow of East River as it is generated by the rising tides into electricity in the grid.
People generally do not know about the energy use from the East River, and they have several other misconceptions about the river itself. The East River is not actually a river, but a tidal strait that connects the Long Island Sound and the Atlantic Ocean. Additionally, it is generally perceived as being an aquatic wasteland due to the centuries of pollution from New York’s harbors. However, the East River, like the Hudson River on the other side of Manhattan, is an estuary, a type of body of water that contains both fresh and saltwater, which allows it to support a vibrant ecosystem. From the continuous pollution, the fish in the East River are not safe to eat, but they are in abundance.
The RITE Project is fully aware of both of these ideas, and Verdant Power has incorporated them into their turbines and research. Since the East River is a tidal straight, it changes its direction of flow throughout the day in accordance with the tide. The turbines work in accordance with the hydrometry, or measurement of liquid flow, of the river by altering their direction approximately four times every day, continuously making use of the tidal power.
During 2006-2009, Verdant conducted a grid-connected demonstration of six turbines. This indicated several things, such as how the turbines were not damaged by any debris, delivered 70 megawatt-hours to commercial end users, and that could operate for at least 9,000 hours. However, the test also took in concerns related specifically to the wildlife in the river. Ultimately, Verdant concluded that it was safe for the aquatic inhabitants, since the turbines move slow enough for fish to swim through them and avoid damage.
A distinct advantage of tidal power over other forms of renewable energy is that it can be easily predicted and monitored. Unlike sunlight and wind flow, the tides of the Earth can be accurately predicted decades in advance. Additionally, with the use of IEC/TS 62600-201 ED. 1.0 EN:2015, Verdant can precisely estimate the system’s annual electricity production. Placing turbines at the bottom of a body of water also avoids the issues with energy generation equipment being out in the open, such as people stealing solar panels and locals opposing wind energy near their homes.