Batteries get the headlines, but hydropower already holds far more storage – much of it unused. HYDROGRID believes software is the key to unlocking it.
The energy transition, argued Janice Goodenough, CEO of HYDROGRID, “is not so much a problem of how much renewable energy can we produce”. Instead, the real challenge is making that energy available when consumers and the grid need it. At Energy Tech Summit, she explained why hydropower storage is central to solving that problem – and how digitalization can unlock capacity that already exists.
Only a handful of storage options
Goodenough counted four technologies that can provide storage today. First, hydropower offers long-duration storage, well beyond a few hours. Second, batteries have advanced rapidly but still store energy for only a few hours, nowhere near day-to-night or seasonal needs. Third, demand response shifts consumption to match supply, yet few applications can realistically follow the wind and sun. Finally, emerging options such as solid-state batteries remain early-stage. As she put it, “I’m not going to hold my breath.”
That means the solutions must come from technologies already available. Batteries will clearly play a major role. Depending on the forecast, battery capacity could grow between 10 and 50 times by 2035. However, that is only half the picture.
Janice Goodenough, CEO of HYDROGRID
Why hydropower storage still outweighs batteries
Even after that growth, hydropower will still exceed battery capacity by a significant margin well beyond 2035. The gap is even wider in storage volume. Measured in megawatt hours, existing pumped hydro dwarfs the battery fleet expected over the next decade. In Goodenough’s words, while battery buildout is fantastic, “an energy transition is not possible without hydropower”.
Pumped storage is only part of the story, though. A large amount of hydropower storage is physically available but goes unused. Many plants have reservoirs, yet their operators lack the digital tools or operational capacity to use them flexibly. Restrictive regulation adds to the problem. HYDROGRID estimates that around 4,000 gigawatt hours of such capacity exist today – more than all the battery storage expected over the next decade.
Turning hydropower plants into smart assets
HYDROGRID’s real-time software collects plant data and combines it with weather and power market data. It then steers each plant intelligently based on grid demand and price signals. The models learn and recalibrate continuously, and the process is fully automated, taking operators “from water to money”.
The software covers everything from simple run-of-river plants, of which there are tens of thousands worldwide, to complex cascades of connected reservoirs. Moreover, it works across climates and market types. Some clients operate in highly liberalized European markets, while others, for example in Brazil, use it mainly for water management. HYDROGRID has clients in 13 countries across three continents.
A case study from the Nordics
Goodenough shared an example from a medium-sized Nordic municipality. Its system links four storage reservoirs. The upper ones hold months of storage, while the lower ones hold only hours. That mix offers huge flexibility – but it is also extremely hard to manage. When heavy rain hits, the generation plan must change immediately. Without round-the-clock control, the operator couldn’t use this “beautiful Ferrari of a battery” and simply ran the plant as baseload.
That approach hurt twice. The grid lost a flexible resource, and the owner missed out on revenue by not selling power when prices were high. After implementing HYDROGRID, however, the plant began dispatching flexibly in response to market prices while keeping every reservoir in balance. Operational effort dropped too, since staff no longer needed to monitor the system 24/7. As Goodenough put it, “Now those operators sleep through the night.”
The plant’s 4.5 megawatts became available to the grid, and the owner’s revenue rose by around 50% compared with the market average. She acknowledged the skepticism: “many people say 50%, that doesn’t sound believable, but it’s possible”.
Janice Goodenough, CEO of HYDROGRID
Takeaway
Europe doesn’t need to wait for new storage technologies to balance a renewable grid. A vast amount of hydropower storage already sits in existing reservoirs, held back by manual operations rather than physics. With intelligent software, those plants can act as green batteries without new capex – supporting the grid and raising revenues at the same time.
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