Hydropower has traditionally been the preserve of vastly ambitious infrastructure projects, reshaping nature and bringing power to millions, such as China's Three Gorges Dam, Brazil's Itaipu, even the Grand Coulee and Hoover Dams in the United States. And while the technology has been scaled down considerably over the years, micro-hydropower whirlpool turbines, designed by the Belgium-based company Turbulent appear to be the first efforts at providing small-scale hydropower renewable energy solutions. Installing these whirlpool turbines requires relatively little effort.
The idea behind Turbulent's design is relatively simple and can be applied directly inside rivers or on land. If installed on land, a hole about 1.5 meters in diameter is dug, with two canals attached to bring the water from a nearby source. A two-level effect is incorporated into the design to help create a whirlpool. A concrete basin is set up inside the hole, containing a generator and impeller, with earth then put back in place. When a river or canal wall is raised, water flows into the basin, creating the whirlpool and powering the turbine.
The whole installation for a single turbine is meant to last around a week. The design and generator come in three sizes, between 15, 30 and 100 kilowatts. The turbine can also be built on an incline, although with a height gradient of no more than 3 meters for a distance of 100 meters.
In a river or canal, the whirlpool turbine is set up directly inside the waterway in a standalone manner. Setting up a single whirlpool turbine in such a way can provide electricity 24 hours a day using the water flow, and can power up to 60 houses in the case of its 100-kilowatt model.
But Turbulent is also aiming to help larger communities that may have problems accessing electricity or that are seeking cleaner alternatives. According to the company, multiple turbines can be set up along the same canal or river, essentially combining their power to provide more energy without the need for a disruptive piece of infrastructure like a dam.
According to the trade publication The Civil Engineer, such hydro-power plants can provide as much as 10 megawatts (MW) in power output, which can produce enough energy to power a small city of 300 people. No matter the size of the installation, the set-up process and maintenance are designed to be hassle-free.Turbulent vows that little maintenance or repairs are required, since the entire turbine has just one moving part, does not affect fish and can be remotely monitored. Since its launch in 2018, the whirlpool turbine has been installed in six different countries, for both residential and industrial purposes.Turbulent has set up these turbines in the likes of France, Indonesia and Chile but its largest project to date, involving six of its biggest 100-kilowatt turbines, is currently being built in Ylang, Taiwan.
Other suitors to the throne of the turbine
Although unique, Turbulent's design is just one of a number of micro-hydropower designs, including some that are literally reinventing the waterwheel.
Lucid Energy, based in Portland, Oregon, place its power system inside existing municipal water systems, essentially generating electricity from the water mains. Known as the LucidPipe Power System, it is low-impact enough that it does not slow down water flow in the slightest. The company signed a deal with the city of Johannesburg in South Africa to install its turbines as a pilot program in the city's water system. The eventual goal: To provide 10% of the system's needs.Another American company, Rentricity, has developed another system to generate electricity from water, specifically for wastewater treatment plants. The battery and fuel cells are placed in the wastewater and can act as a back-up supply to power operations and water treatment functions. This application has also been broadened to power a city's entire water operations. Rentricity turbines power the water distribution operations of Richmond, Utah, as well as other towns in Colorado and Utah.Other proofs of concept have also shown promise. The portable generator from Enomad Uno (formerly known as Estream), for example. may have been among the smallest hydropowered battery in the world, and is being used to power smartphones or tablets. In addition, the three-pronged, turbine-shaped Enomad Uno can be placed behind a boat or even a kayak to store energy and charge electronic devices. The company, Enomad Corp, also proposes a number of other off-the-grid microhydropower solutions.
What does the future hold?
Recent months have shown that microhydropower projects may be undergoing a watershed moment. Countries such as Ghana and Malaysia, which have struggled to sustainably and reliably bring power to remove communities, have set up microhydropower plants in late 2019 and early 2020. Researchers from the United Nations Development Project (UNDP) in the Asia-Pacific region lauded microhydropower in April 2020, saying it was "transforming a community's way of life." Their praise came after one such project on Indonesia's island of Sumatra brought electricity to 4,000 people for the first time.Upon seeing its potential to both save on emissions in more developed economies and to bring sustainable power in remoter, less developed areas, governments and the private sector alike are pouring resources into advancing microhydropower. The US Department of Energy launched a dedicated page to the technology, providing explanations about the different kinds of turbines and resources for homeowners and businesses who may be thinking about installing one. The National Center for Advanced Technology has also made microhydropower one of its signature projects for the future.However, there are still obstacles to overcome. For example, the ease of installation and low maintenance of many smaller hydropower designs mean there may be an assumption to leave them unsupervised or to not provide follow-up funding. Two years after 55 small-scale hydropower projects were installed in the Indian state of Himachal Pradesh, a lack of additional funding resulted in many of them not working.
Microhydropower may not yet be the most obvious choice for communities and households wishing to go off the grid or to make use of their water resources. But with the range of emerging technologies, their increasing adaptability and the range of scenarios in which they can be deployed shows promise for the future.
The author: Chris Dalby
Energy and political journalist with experience covering politics, energy, oil and gas, mining, finance, business, Latin America, China, and the Olympics.
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