Energy sits at the heart of modern life, quietly powering our homes, hospitals, schools, and industries. But we only truly notice it when it stops. When energy systems fail, everything stops – economies stall, essential services falter, and public trust in institutions weakens. Today, in a period of extraordinary geopolitical instability, energy is no longer just a matter of infrastructure, it has become one of the defining strategic questions of our time.
We are living through a period of rising tensions, fragmenting supply chains, and intensifying climate impacts. At the same time, global electricity demand is accelerating rapidly, driven by electrification, industrial digitalisation, and the massive power requirements of artificial intelligence. In this volatile new reality, the defining characteristic of a strong energy system is no longer its sheer scale or production capacity.
It is flexibility. In an unstable world, rigidity becomes risk.
Recent conflicts have driven renewed volatility in global oil and gas markets. While we cannot predict exactly how prices will fluctuate in the coming months, that unpredictability is precisely the point. It underscores why we must insulate economies from price shocks by building grids that rely on renewables and flexible power.
In 2025, renewable energy surpassed coal globally (1) as a source of electricity generation. In China, more than 60% of new power generation comes from wind and solar, while across Europe, renewables now produce more electricity than fossil fuels. This shift is driven by economics, not ideology. Solar and wind are the cheapest sources of electricity the world has ever seen. They scale quickly and improve energy independence. Despite political noise, the transition is moving forward because markets and technology are driving it.
The real question we face today is not whether renewables will dominate our power systems, but rather are our power systems ready for that reality.
For more than a century, fossil fuels gave us predictability – supply simply followed demand. That model worked in a stable world, but we no longer live in that world. Today, we are placing twenty-first-century demand on twentieth-century power systems, and the cracks are showing.
In systems with high renewable penetration but insufficient flexibility, we see rising curtailment, extreme price volatility, and grid instability. In the UK alone, renewable curtailment cost more than £1 billion last year (2), while Chile wasted 19% of its solar and wind generation in 2024 (3). These are not failures of renewable energy. They are failures of system design. The solution is not to slow down the transition, but to design it properly.
At Wärtsilä, our modelling of power systems worldwide, from large, interconnected grids to small island nations, yields a consistent conclusion: renewables alone are not enough. They must be paired with flexible balancing generation and energy storage.
Energy storage provides an instant response, stabilising frequency and absorbing short-term fluctuations. Meanwhile, flexible generation provides longer-duration balancing, quickly ramping up and down as renewable output changes. Together, they enable systems that are both highly renewable and highly resilient.
Importantly, this approach does not lock in yesterday's fuels. Modern engine power plants are fuel-flexible and future-proof. While they operate on gas and hydrogen blends today, they can transition to sustainable fuels like hydrogen, ethanol, or ammonia tomorrow, ensuring today's investments do not become stranded assets.
We have seen this model work in practice. Two years ago, we partnered with Aqualectra, the utility company for the Caribbean island of Curaçao, to help them meet their bold sustainability targets and strengthen grid reliability. By redesigning their system to integrate renewables, energy storage, and flexible balancing, we helped deliver a more stable grid and greater affordability.
What made this partnership unique was the commercial model: a long-term decarbonisation services agreement where our compensation is directly linked to how well we optimise the energy system. This isn't just a local success story; it is a blueprint for fragile, high-cost grids worldwide.
The benefits of system-level thinking extend far beyond island grids. Wärtsilä’s global modelling shows that combining renewables with energy storage and balancing power, like engine power plants, could reduce global system costs by up to €65 trillion over the next 25 years, compared to a renewables-only pathway. It could reduce wasted, curtailed energy by nearly 90%, cut emissions faster, and halve the amount of energy capacity and land required to achieve the same goals.
Sustainability, affordability, and resilience are not competing goals; they are interdependent ones.
If the benefits are so clear, why isn't this happening everywhere? Because technology alone is not enough. Market designs and regulatory frameworks still reward raw energy production over total system performance. Flexibility is too often treated as a technical afterthought rather than a strategic asset.
We have all the tools we need in the toolbox, there is no excuse not to use them. Uncertainty in the world around us is not an excuse for inaction. We can either rely on short-term fixes and hope our legacy grids hold together, or we can deliberately design power systems that are flexible, resilient, affordable, and sustainable.
Flexibility is not a compromise. It is the definitive strategy that allows us to move faster, and with absolute confidence, into the future.
1) https://ember-energy.org/latest-insights/global-electricity-mid-year-insights-2025/
2) https://www.energyvoice.com/renewables-energy-transition/581777/uk-wind-curtailment-1bn/
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