16 April 2023 |

Undamming hydropower growth


I helped judge the MIT Climate and Energize prize competition on Thursday (you can watch all 8 hours of it here; pitches started around the 2-hour and 30-minute mark). Eight startup teams from across the U.S. and Europe competed. Their proposed solutions spanned everything from long-duration energy and heat storage to carbon removal. 

Notably, none of the teams were pitching new or improved power generation technologies. When the competition started 16 years ago and was called the ‘Clean Energy’ prize, I imagine few teams were working on anything besides that.

There’s a good reason for the shift in focus. Since 2007, the world has made a lot of headway in figuring out how to build, deploy, and finance clean energy technologies. Most of the remaining work in the energy transition could be borne by building infrastructure; it doesn’t depend on inventing new generation technologies (new energy storage solutions are still needed and welcome).

Still, that doesn’t mean we should abandon novel renewable energy concepts entirely. One firm that announced a new fundraise this week wants to deploy more distributed hydroelectric systems across existing waterways. Their turbines are to canals what solar panels are to roofs. Let’s take a look. 

Undamming hydropower

Hydroelectric power has been around for a long time and still holds the crown as the #1 source of renewable energy globally, producing about as much power as solar and wind combined (for now). Most hydroelectric generation stations are big dams. At least back in 2016, of the ten largest power plants in the world, nine were dams.

There are other, smaller power generation technologies that harness the flow of water. The concept has been around for a long time. Think about the old grist mills for grinding grain you’ve probably seen in Europe or the East Coast. Now, Emrgy, based out of Atlanta, wants to build more flow-of-water systems in the 21st century. The firm makes hydroelectric turbines designed for canals, rivers, and other waterways and announced an $18.4M Series A this week, led by Oval Park Capital.

Because many of the best sites for hydroelectric dams were developed in the 20th century, hydroelectric power generation capacity globally (ex-China) hasn’t grown quickly since the 1990s. The Chinese are still building new hydroelectric capacity, both in China and abroad. But China is the exception, as they’ve developed every power generation hand over fist.

However, technologies like Emrgy’s could be vital in undamming hydroelectric power growth in developed countries. Their turbines come with a few advantages:

  • Like solar arrays are comprised of small panels that can combined ad infinitum, Emrgy’s turbines come in 5 to 25 kW modules that can be connected to create larger arrays (the firm targets 10 to 20 MW arrays). Manufacturing smaller systems like this to spec is more scalable than building big dams that need to be customized to unique sites. 
  • Like solar panels deployed on existing roofs, plenty of waterways are already surrounded by grid infrastructure and industrial operations where Emrgy could deploy its turbines. The U.S. Bureau of Reclamation operates 1,600 miles of main canals.
  • Financing smaller, modular hydroelectric systems should also be more straightforward than massive dams. Even bigger, utility-scale solar projects follow a pretty tried and true project and tax equity financing playbook at this point. Ideally, Emrgy can slot their systems into similar frameworks.
Emrgy’s turbines deployed on a river in Denver (via Emrgy)

Perhaps most importantly, hydroelectric power has a higher capacity factor than solar and wind. Running water is more consistent – although drought conditions can still pose a threat – than sunshine and wind, making innovation in long-duration energy storage and new electric transmission infrastructure less of a prerequisite to take full advantage of hydropower. 

With funds in tow, Emrgy plans to open its first major manufacturing facility in Aurora, Colorado, to produce up to 5 MW of turbine capacity monthly. It has successfully deployed its turbines both domestically and internationally already.

The net-net

It can take decades to build a new transmission line or nuclear power plant in the U.S. Against that backdrop, it’s no wonder that a lot of renewable energy capacity and power generation growth has come from more distributed systems like solar panels and wind turbines, where the underlying modules are easier to scale from a manufacturing perspective and easier to deploy.

Designing hydroelectric turbines to follow the manufacturing and deployment path that solar paved makes a lot of sense. If Emrgy can make it make cents, too, their future should be bright!