Research and Development

NREL researchers develop Real-Time Hydropower Emulation Platform

NREL researchers develop Real-Time Hydropower Emulation Platform
(photo courtesy NREL)

Experts at the National Renewable Energy Laboratory (NREL) have designed a Real-Time Hydropower Emulation Platform, which uses field data from actual hydropower plants, mathematical models and hardware to recreate hydro plants in a virtual lab setting.

Consider two scenarios: First, a severe winter storm hits the Midwest. Power outages strand residents in freezing temperatures for hours. Yet, the area’s hydropower plants could jump-start the grid if they had the right system to do so. The second takes place in the remote Alaskan city of Cordova, which can run its local grid on hydropower alone — in the summer, at least. Once winter blows in, water stays frozen, and avalanches can rumble through, cutting off power when temperatures are at their lowest.

Both of these scenarios are examples of where hydropower could — but cannot quite — fulfill its role as the reliable backbone of our power grids, NREL said. As the U.S. adds more and more renewable energy to the grid, hydropower’s steady, affordable energy is key to making the grid dependable and resilient. But today’s plants could be even better, and more flexible, if researchers can find a better way to study these big, complex facilities.

NREL’s Real-Time Hydropower Emulation Platform allows users to study how various hydropower plant designs are likely to operate in the real world and in real time, providing a low-cost, low-risk way to test new hydropower technologies and grid configurations.

“We want the field to come to the lab,” said Mayank Panwar, lead researcher on the three-year project, which is funded by the U.S. Department of Energy’s Water Power Technologies Office (WPTO) as part of its Water Innovation for a Resilient Electricity System (HydroWIRES) Initiative.

Panwar’s hydropower emulation platform got started thanks to the WPTO Seedlings and Saplings program, which supports creative, high-risk, high-reward ideas in water power. With this initial investment, Panwar and his team set out to solve a big challenge that can hinder the hydropower industry from adopting new technologies and designs: How do you test something you cannot build?

Researchers can build a new solar photovoltaic system to validate in the field. But building a hydroelectric prototype is often impractical, time-consuming and expensive because these plants are so large and depend on specific geographies to operate. And tinkering with operational facilities is risky. Tests could cause irreversible damage.

Even so, new hydropower technologies and grid configurations are perhaps more critical today than ever before. As the U.S. transitions to a 100% clean energy power grid, hydropower’s flexible, reliable energy and energy storage will play a big role in keeping that grid running smoothly. And how hydropower could support a future clean energy grid is not well-understood.

“It’s a significant addition to our emulation platform” said Rob Hovsapian, a senior research advisor at NREL, who helped build the platform. “Hydropower needs to live with the changing grid, and we want to make it a better resource in terms of flexibility and reliability.”

To provide that flexible, reliable energy, the hydropower industry is using more power electronics, which give them finer control over their plants’ energy output. Greater control means plants can quickly respond to cyber and natural threats, like the severe winter storm that knocked out power in the Midwest.

In the Seedlings project, Panwar and his colleagues collected field data from hydropower plants operating in Cordova. Then, using machine learning, they designed software representations that could realistically imitate a hydropower plant, including its electronic controls, turbines, hydraulic and mechanical circuits, and even water flows — all in real time.

But how do you realistically imitate a real-life grid? To learn how these new hydropower designs might integrate into various grid systems, Panwar and his team turned to NREL’s Advanced Research on Integrated Energy Systems (ARIES). With ARIES, one of DOE’s largest digital grid simulation platforms, the hydro emulation platform could mimic how hydropower plants might pair up with energy storage and other renewable energy technologies to provide more reliable energy to a grid.

ARIES also provides an opportunity to connect the team’s software to hardware, like rotating machines that represent a hydropower plant’s rotating turbine, to get as close as possible to replicating a real-life plant in the safety of a controlled lab environment.

Next, Panwar and his team plan to scale up their platform to mimic plants that can generate megawatts of energy (right now the platform is capped at 2.5 MW). Eventually, Panwar hopes the industry sees his platform as its go-to test bed.