Clean Power Run-of-river diagram (

Published on April 21st, 2014 | by Sandy Dechert


Run-Of-River Hydro May Expand Tenfold Over Next Decade

April 21st, 2014 by  

Hugh Keenleyside Dam and the Arrow Lakes power plant (wikipedia).Hugh Keenleyside Dam, a run-of-river hydropower station operated by BC Hydro, and the Arrow Lakes Generating Station

“Run-of-river” hydro power, gentler and smaller-scale than massive hydroelectric projects that irretrievably flood huge areas of land, may become a $1.4 billion-dollar industry in the next 10 years, according to Tocardo International BV, a Dutch turbine maker.

To many, run-of-river technology represents the most environmentally friendly hydropower because it lacks the enormous investment and impacts of traditional impoundment projects. Tocardo general director Hans van Breugel explains its appeal to companies and investors:

The advantages of river-turbine projects are you don’t need to build infrastructure, they’re easy to install and maintain, and they can be easily connected to the local grid. Within a year you can start installing these projects, whereas hydropower projects can take 12 to 15 years.

The projects also involve nearly zero greenhouse gas emissions and no mercury or particulate pollution.

Run-of-river diagram ( is actually a diversion strategy that redirects part of a downward-flowing waterway through a pipe down the head (elevation change) to spin turbines and generate electricity at a lower powerhouse. From the powerhouse, the water then rejoins its source. Upstream storage (pondage) is minimal and used only on a daily or weekly basis. It’s an ideal generation scheme for remote, mountainous areas and has been used with much success in areas of the Pacific Northwest and Himalayan Asia.

The infographic above from shows how the process works. Key to impact prevention is flow maintenance monitoring (i.e., ensuring that the waterway never drops below the level needed to protect ecological health of water and habitats, which are diverse because of the topography). Fish ladders can enable migration for species such as salmon and white sturgeon.

Tocardo turbine ( says that its turbines are easily installed, reliable, and low-maintenance. River sites, inshore sites, and offshore sites can all use the same turbines, either on or off the grid. The facilities run from 500kWh to 1 MWh and the technology already is cost-competitive with fossil fuels, Van Breugel says.

The company first implemented its design to harness tidal streams at Den Oever, Holland. There it has been generating power for five years. Two years ago, Tocardo started working in Nepal, and it expects to expand soon to South America, particularly Chile, Brazil, and Argentina.

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About the Author

covers environmental, health, renewable and conventional energy, and climate change news. She's currently on the climate beat for Important Media, having attended last year's COP20 in Lima Peru. Sandy has also worked for groundbreaking environmental consultants and a Fortune 100 health care firm. She writes for several weblogs and attributes her modest success to an "indelible habit of poking around to satisfy my own curiosity."

  • Wayne Williamson

    These kinds of hydro are non invasive, but they have no storage capacity. Some of the great things about dams is the ability to provide energy even when the river is not flowing. That being said, with the kind of usage this hydro uses, it could potential be put anywhere there is a x amount of drop within a y amount of miles. Don’t know what the x and y and probably z-flow is….

  • Offgridmanpolktn

    These remind me of smaller scale equipment available to generate electricity for offgrid homes, with the same principle of diverting a part of the flow to run through a water turbine. With those though it has been found to get much better efficiencies running it through a small Pelton wheel generator with 2-10 gallons/minute providing sufficient kwh when there’s enough head pressure (drop from source to generator). As compared to using in stream turbines mentioned here.
    Can someone explain why these wouldn’t scale up to work in the situations described here? It would seem using 1/10 – 1/100th of the total flow through a Pelton generator as opposed to in stream turbines requiring monitoring of the total stream flow would be more efficient and less harmful to the environment.

  • I worked at that dam as it was being constructed back in 2003.

    Kiewit Corporation (then called Peter C. Kiewit and Sons) and Columbia Hydro Constructors were the main contractors.

    Both Kiewit Corp and CHC are noted for completing projects on-time and on-budget.

    And both paid close attention to sustainable construction practices.

    I’m pleased to say it is a picturesque site and it is located in a beautiful part of British Columbia and remains a worthwhile addition to the nearby town of Castlegar, BC.

    FYI: Some well-known movies have been (partially) filmed near there.

    Cheers, JBS

  • Matt

    When I went to Holland the first time 15 years ago, I visited some of the dike projects. And there is this massive flow running through them when the tide is changing. And I wondered then why they didn’t generate electric off that flow. So these are low head turbines. If I can do pipes for a big head drop then existing turbines are likely better. But think of all the in river dams that are used today only for flood and navigation control. Since the dam is already built, all you need to do is add the turbines next to it, and then run the water through them instead of over the top. In the US just the Mississippi and the rivers that feed it would be massive.

    • Michael Berndtson

      Maybe those turbines could puree the exploding asian carp population into a fine meal in the Mississippi and Illinois rivers. The carp puree could be sucked off the surface via vacuum dredge, dewatered and sold to McDonalds for sustainable filet o’ fish sandwiches. I’m just the idea guy here. There might be some details to work out.

      • Ronald Brakels

        Hmmm… you sure you want that to be sustainable? Maybe you should let the carp slayers operate in an unsustainable way and let the Mississippi cod or the steamboat sturgeon or whatever are the indigeonous species in that area make a comeback. Of course they’ll need some sort of friend or foe detection system so they don’t process the wrong fish, but that should be okay. According to the computer game Bioshock they had that sort of thing all sorted out in 1960.

        • Michael Berndtson

          My comment was dumb. Your reply is kind of brilliant. Chicagoland is looking to spend somewhere between $1 billion and $20 billion to deal with the asian carp – keeping it from swimming or being dropped by birds into Lake Michigan. On the other hand, kudzu hasn’t been dealt with and its what, 50 years later? There’s already two electric fences along the sanitary and ship canal to, I’m assuming, zap asian carp. In that vain, they could just not treat the wastewater from the Stickney works and make Des Plaines, Illinois and lower Mississippi uninhabitable to just about everything.

          • Ronald Brakels

            Australia is also infested with carp. They grow to the size of sharks (small sharks), taste awful, have to be bled to be slightly edible, are full of bones, and eat trees. Fish should not eat trees. But then rabbits each trees in Australia, as well as each other. There seems to be something about Australia that drives introduced animals bonkers. Actually, the first Dutch people to settle here also ate each other. Now I’m wondering about my father’s delicious roast pork.

          • A Real Libertarian

            Did he say it came from a “long pig” or anything like that?

          • Bob_Wallace

            The other, other white meat.

          • A Real Libertarian

            Do you mean cat, or the other, other, other white meat?

          • Bob_Wallace

            Long pig.

          • A Real Libertarian

            So the other, other, other white meat.

          • Calamity_Jean

            Cat, AKA “roof rabbit”.

          • Bob_Wallace

            “Little tiger”. Goes great with beer.


          • A Real Libertarian


            You have the most difficult to procure part of Dragon, Phoenix, Tiger and you waste it like that?

            Plus, it’s a kitty. It will give you food poisoning out of spite.

            Why do you think the Internet loves cats so much? It’s because cats are the only assholes as big as they are.

          • Calamity_Jean

            Well, it was called “roof rabbit” in Victorian England.

          • Calamity_Jean

            Grind them up to make fertilizer. Or fish food for more edible species of fish (shrimp farming?). You’re right that fish shouldn’t eat trees, ug.

          • Ronald Brakels

            Gotta catch ’em first. That’s the hard part.

          • Bob_Wallace

            You guys don’t have dynamite?

          • A Real Libertarian

            Australia, Bob.

            If machine guns don’t kill the birds, why would dynamite kill the fish?


          • Bob_Wallace

            That was an interesting read. Probably best they don’t try fishing with dynamite. Probably throw the match in the water and hold on to the stick.

          • A Real Libertarian

            Check out the “Real Life — Australia” section (Warning, TV Tropes):


          • Ronald Brakels

            If anyone knows about explosives safety it’s old Australians. In fact, they err a little too far on the side of safety. Every time Grandad tried to remove the key from a tin of sardines he’d forget what he was doing and hurl them out the window.

          • Bob_Wallace

            I think Asian carp have already been found above the electric fences.

          • Michael Berndtson

            If anything can live in the sanitary and ship canal then we should be worshiping it. Or splice their DNA with humans. To survive any pending apocalypse. To the internet: that was not meant to be an actual suggestion. Just trying to lighten up the comments section.

          • Bob_Wallace

            Just start partying with jellyfish. They seem to be the cockroaches of water.

  • JamesWimberley

    It seems to be a return to the principle of mediaeval and early modern watermills, also run from side channels parallel to the main stream (millraces).

  • Michael Berndtson

    Interesting stuff. As alpine areas get more precipitation as rain and less as snow we’ll probably need to adjust how we take advantage of potential energy. And as glaciers and snowpack melt faster, we should take away some of that energy before it reaches the sea and becomes zero.

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