The transition to a net-zero future is frequently framed as a leap into the unknown. However, at Wärtsilä, we have spent years decoding the world’s most complex energy landscapes. The journey is no longer a matter of guesswork; it is a matter of science.
By leveraging advanced PLEXOS software, it is possible to simulate every minute of a year, taking into account real-life weather patterns, fuel costs, grid constraints, the mix of technologies and future investments plans.
The data from over 200 global power system models underpins a universal trajectory of the energy transition. Regardless of geographic location or starting point, the path always consists of deploying renewable capacity (wind/solar), building short-term energy storage, and utilising rapid-response flexible balancing power to ensure grid stability. The modelling has also shown that a flexible, renewable-led system is not just technically achievable, it is the most economically viable path we can take.
Global analysis proves that deep decarbonisation cannot be achieved through renewables alone; you need balancing technologies to manage the inherent variability of wind and sun.
Our modelling outlines a five-step path towards a 100% renewable energy future:
1. Add more renewables to the power mix: Renewables are already the most cost-effective path for new power but scaling them to lead energy systems is the real challenge. Acting early unlocks long-term value, reducing carbon costs while strengthening energy independence.
2. Add flexible power plants & energy storage: Flexibility is the essential partner to renewables. Our global analysis of over 200 power systems proves that you cannot achieve deep decarbonisation with renewables alone; you need balancing technologies, such as engines and energy storage, to manage the inherent variability of wind and sun.
3. Phase out inflexible power plants running on coal: Inflexible, baseload plants like coal are the biggest obstacles to a modern grid. Wärtsilä’s data-driven approach identifies exactly how these "must-run" units force the curtailment of clean energy.
4. Convert all power plants to run on sustainable fuels: As the grid nears 100% renewables, the final path of decarbonisation requires a shift in fuel, not just technology. Wärtsilä recognises that achieving a 100% renewable energy future will require integrating new sustainable fuels into the mix. Power-to-X solutions facilitate this by transforming surplus renewable power into carbon-neutral energy carriers.
5. Phase out remaining fossil fuel capacity: The final step is the culmination of years of strategic optimisation. Once the grid is supported by a mix of renewables, energy storage, and flexible balancing power running on 100% sustainable fuels, the remaining fossil fuel capacity can be retired.
The effectiveness of this data-driven approach is validated by Wärtsilä’s massive global footprint, including 81 GW of power plant capacity and over 130 energy storage systems delivered over 180 countries.
Our research demonstrates that a flexible, renewable-led system is the most cost-effective way to achieve carbon neutrality, regardless of a country's starting point.
The shift toward an integrated, flexible grid is more than an infrastructure upgrade; it is a global economic reset. Our modelling indicates that by 2050, we could see €65 trillion in reduced costs and a 21% reduction in emissions compared to a pathway where only renewables and energy storage are implemented.
By front-loading these investments today, countries can avoid the rising costs of carbon taxes, eliminate waste, and secure long-term energy independence. The technology and the data exist; the only remaining variable is the speed of action.
Once every six weeks, you will get the top picks – the latest and the greatest pieces – from this Insights channel by email.
