Water at the heart of energy security: Turnbull warns Europe after Iberian blackouts

The blackouts that swept across Spain and Portugal last week have reignited a crucial conversation about the role of water in energy resilience. For Malcolm Turnbull, former Prime Minister of Australia and now President of the International Hydropower Association, the events in Iberia underscore a hard truth: without the flexible, stabilising power of hydropower — especially pumped storage — grids will remain vulnerable, no matter how clean their energy mix becomes.

“When I was Prime Minister of Australia, it was the fear of blackouts and brownouts that drove me to champion the Snowy 2.0 pumped storage hydropower project,” said Turnbull. “Australia was undergoing a rapid influx of solar generation. That was a good thing — but it brought new vulnerabilities. I realised that unless we invested heavily in storage and grid flexibility, the stability of our energy system — and the lives of millions of Australians—would be at risk.”

Hydropower — and especially pumped storage — is one of the most mature and effective tools for stabilising grids as they transition toward renewable sources. But it’s also one of the most undervalued. For Turnbull, that oversight is part of a deeper systemic failure to think holistically about energy.

While he recognised the immediate causes of the Iberian blackouts may differ from what Australia faced, he underscored that energy security must be thought of at the level of the grid, not just individual sources of generation, because failing to do so has real, tangible consequences.

“What matters most is grid stability and system reliability,” he said. “The question must not be: ‘Is this source cheap?’ or ‘Is that technology clean?’ It must be: ‘Can this grid deliver reliable, affordable, clean electricity whenever people need it?’”

He described long-duration energy storage as “the ignored crisis within the crisis”, and warned against relying on batteries alone as a solution. “They are cheap, easy and quick to install. As a recovering politician, I can fully appreciate the attraction,” he said about batteries. “They certainly have a vital role to play, especially for short-duration balancing. But relying on batteries alone for long-duration storage is a red herring.”

“They cannot feasibly or affordably provide the level of multi-hour, multi-day energy backup needed to keep entire grids stable at scale.”

Instead, Turnbull pointed to pumped storage hydropower (PSH) — a solution with over a century of proven performance — as the backbone of global energy storage. Today, PSH provides over 90% of the world’s long-duration storage capacity, and its potential remains vast.

“China and India have understood this,” Turnbull said. “Together, they are building more than 200 GW of new pumped storage capacity to back up their enormous investments in solar and wind. Europe, unfortunately, is coming late to the party.”

Though Spain and Portugal are considered leaders in European PSH — with trailblazing projects like La Muela and Alqueva — Turnbull warned that even they are not keeping pace with the accelerating demands of grid decarbonisation.

“More investment, faster permitting, and stronger integration of hydropower into national energy strategies are essential,” he said, “if Europe is to secure a stable, resilient energy future.”

Beyond storage, Turnbull stressed the wider benefits of hydropower as an energy source that is both renewable and flexible. Its ability to quickly ramp up, stabilise voltage and frequency, and support system reliability makes it indispensable — not just for the clean energy transition, but for crisis response.

“It is no coincidence that in Iberia, as so often, hydropower was the first responder technology to get the grid up and running,” he said. “The recent blackouts in Iberia remind us that no energy transition can succeed if it sacrifices reliability for speed or ideology. Clean energy without grid security is a false promise.”

As countries weigh the path to net zero, Turnbull’s message is clear: a stable, flexible, and decarbonised grid is possible; but we need to treat storage not as an afterthought but as the foundation of energy security.