As the world races to decarbonize and build a net-zero future, a critical question looms over the global energy transition: Where should we invest our trillions? The answer, according to new research from Boston University’s Institute for Global Sustainability (IGS), is becoming increasingly clear.
A groundbreaking study published in Energy Research & Social Science reveals that nuclear power is by far the most expensive and risky type of energy infrastructure, with massive cost overruns, extreme delays, and little promise of improvement. By contrast, solar and wind energy projects consistently beat financial expectations, finishing faster and for less money.
As governments, investors, and utilities weigh their options, the financial case for renewables just became too strong to ignore.
Top Three Takeaways from the Article:
Nuclear power is the most expensive and high-risk energy investment, with average construction cost overruns exceeding 100% and delays that add over $1.5 billion per project, making it financially unviable for rapid decarbonization.
Solar and wind energy consistently outperform other energy sources in both cost and construction time, often coming in under budget and ahead of schedule, offering not just environmental benefits but strong financial returns.
Smaller, modular renewable projects present lower risk and better scalability, suggesting that future energy investments should shift away from massive centralized systems like nuclear and focus instead on distributed renewable infrastructure.
Nuclear Power: High Risk, High Cost, Low Return
The IGS study analyzed 662 energy projects across 83 countries, representing $1.358 trillion in investments between 1936 and 2024. The verdict on nuclear energy was damning:
- Average cost overrun: 102.5%
- Average excess cost per plant: $1.56 billion
- Consistent multi-year delays
No other energy source performed worse. In fact, nuclear reactors more than double their expected costs on average. This isn’t a fluke, it’s a pattern stretching across decades, continents, and political systems.
And it’s not just about money. These delays mean lost years of climate progress, as carbon-intensive systems stay online while overbudget nuclear projects remain incomplete.
The Hydrogen Hype and Carbon Capture Pitfall
While nuclear gets the worst marks, other “emerging” technologies like hydrogen and carbon capture and storage (CCS) also fared poorly in the study. Both show:
- Frequent and significant cost overruns
- Severe delays
- Uncertain scalability
These are technologies often touted as climate silver bullets, but the study raises serious concerns about their reliability and return on investment.
As Benjamin Sovacool, lead author of the study, put it:
“Worryingly, these findings raise a legitimate red flag concerning efforts to substantially push forward a hydrogen economy.”
Renewables Shine: Solar, Wind, and Grid Projects Lead the Way
On the opposite end of the spectrum, the cleanest and most sustainable technologies, solar power, wind farms, and high-voltage grid transmission lines, consistently delivered:
- Lower construction risk
- Smaller cost overruns
- Shorter build times
- Higher budget predictability
Solar projects, in particular, often came in under budget and ahead of schedule, a rarity in large-scale infrastructure. Wind power wasn’t far behind. Together, they represent not just environmental progress, but financial stability.
“Low-carbon sources of energy such as wind and solar not only have huge climatic and energy security benefits,” says Sovacool, “but also financial advantages related to less construction risk and less chance of delays.”
The Bigger They Are, The Harder They Fall
One of the study’s more surprising conclusions was about scale. Projects larger than 1,561 megawatts were far more likely to suffer runaway costs and delays, regardless of technology.
This finding has major implications for how we plan our energy future. Rather than pouring billions into massive centralized plants (nuclear or otherwise), we may be better off building smaller, modular renewable systems that are easier to control, cheaper to build, and faster to deploy.
A Financial Warning, Not Just a Climate One
What this study confirms is something environmentalists have long argued: Nuclear power is not only dangerous and slow, it’s also wildly expensive. And as the urgency to cut carbon emissions grows, we simply don’t have time or money to waste.
As nations gear up to invest over $100 trillion in energy infrastructure by 2050, the IGS study offers a clear guidepost:
If we want speed, stability, and sustainability, the future is solar and wind, not nuclear.
Put the Money Where the Return Is
This isn’t just about emissions. It’s about economics. About efficiency. About using public and private dollars wisely to build the future we need, not to chase outdated, risky technologies from the past.
The numbers are in. The risk is clear.
Solar and wind aren’t just cleaner, they’re smarter investments.
And nuclear? It’s the most expensive detour on the road to climate progress.