As droughts reduce hydropower and clouds dim solar output around the world, experts say meteorology and climate science must be at the heart of the energy transition.

By Laura Quinones

The race towards renewable energy is accelerating, and for all the looming challenges of the climate crisis, signs of progress are there: Solar panels are beginning to blanket deserts, wind turbines dot coastlines, and hydropower dams are harnessing powerful rivers to churn out clean electricity.

Yet, even as the push for renewables gains momentum – driven by cheaper technology and an urgent need to slash carbon emissions – experts are waving cautionary flags: Because renewable energy sources depend on weather conditions, climate change is increasingly dictating, and jeopardizing, renewable energy production.

This trend became more pronounced in 2023, marked by a volatility that disrupted renewable energy generation globally. Temperatures soared 1.45°C above pre-industrial levels, and the shift from La Niña to El Niño altered rainfall, wind patterns, and solar radiation.

Hamid Bastani, a climate and energy expert with the World Meteorological Organization (WMO), provided a stark example of this impact. “In Sudan and Namibia, hydropower output dropped by more than 50 per cent due to unusually low rainfall,” he said in an interview with UN News.

In Sudan, rainfall totaled just 100 millimeters (less than four inches) in 2023—less than half the national long-term average.

“This is a country where hydropower makes up around 60 per cent of the electricity mix. These reductions could have significant implications,” Mr. Bastani explained, noting that the power system supports a large and rapidly growing population of about 48 million.

These shifts were not limited to hydropower. Wind energy, too, showed signs of stress under changing climate conditions.

China, which accounts for 40 per cent of global onshore wind capacity, saw only a modest 4 to 8 per cent increase in output in 2023, as wind anomalies disrupted generation. In India, production declined amid weaker monsoon winds, while some regions in Africa experienced even sharper losses, with wind output falling by as much as 20 to 30 per cent.

South America, meanwhile, saw the scale tip in the other direction. Clear skies and elevated solar radiation boosted solar panel performance, particularly in countries like Brazil, Colombia, and Bolivia.

As such, the region saw a four to six per cent increase in solar generation – a climate-driven bump that translated to roughly three terawatt-hours of additional electricity, enough to power over two million homes for a year at average consumption rates.

“This is a good example of how climate variability can sometimes create opportunity,” explains Roberta Boscolo, who leads WMO’s New York Office and formerly the agency’s climate and energy work. “In Europe, too, we are seeing more days with high solar radiation, meaning solar power is becoming more efficient over time.”

Ms. Boscolo and Mr. Bastani are among the contributors to a recent WMO–IRENA study examining how climate conditions in 2023, shaped by El Niño, global warming, and regional extremes, affected both renewable energy generation and energy demand worldwide.

Solar power accounted for over 73 percent of all new renewable capacity added globally in 2023, making it the fastest-growing source of energy worldwide.​

Systems built on stability, in a world that is anything but

Ms. Boscolo, who has spent years working at the intersection of climate science and energy policy, is quick to point out the vulnerability of renewable energy infrastructure. Dams, solar farms, and wind turbines are all designed based on past climate patterns, making them susceptible to the changing climate.

Take hydropower. Dams rely on predictable seasonal flows, often fed by snowmelt or glacial runoff. “There will be a short-term boost in hydropower as glaciers melt,” she said. “But once those glaciers are gone, so is the water. And that is irreversible – at least on human timescales.”

This pattern is already unfolding in regions like the Andes and the Himalayas. If the meltwater disappears, countries will need to replace the way they generate power or face long-term energy deficits.

A recent report from the UN Environment Programme (UNEP), for example, pointed out that rising sea levels and stronger storms pose growing risks to energy production facilities, including solar farms located near coastlines.

Similarly, increasingly intense and frequent wildfires can also take down power lines and black out entire regions, while extreme heat can reduce the efficiency of solar panels and strain grid infrastructure—just as demand for cooling peaks.

Nuclear power plants are also at risk in the changing climate.

“We have seen nuclear power plants that could not operate because of the lack of water… for cooling,” Ms. Boscolo said. As heatwaves become more frequent and river levels drop, some older nuclear facilities may no longer be viable in their current locations.

“This is another thing that should be looked at with different eyes in the future . When we design, when we build, when we project power generation infrastructure, we really need to think about what the climate of the future will be, not what was the climate of the past”.

Global renewable electricity capacity grew by nearly 50 percent in 2023—the largest annual increase in two decades—with most additions coming from solar and wind.​

Adapting to the future through data, AI and technology

The expert underscores that one thing is certain: Our planet is heading towards a future in which electricity, especially from renewable sources, will be central.

“Our transport is going to be electric; our cooking is going to be electric; our heating is going to be electric. So, if we do not have a reliable electricity system, everything is going to collapse. We will need to have this climate intelligence when we think about how to change our energy systems and the reliability and the resilience of our energy system in the future.”

Indeed, to adapt, both experts emphasized a need to embrace what they call climate intelligence – the integration of climate forecasts, data, and science into every level of energy planning.

“In the past, energy planners worked with historical averages,” Mr. Bastani explained. “But the past is no longer a reliable guide. We need to know what the wind will be doing next season, what rainfall will look like next year – not just what it looked like a decade ago.”

In Chile, for instance, hydropower generation surged by as much as 80 per cent in November 2023, due to unusually high rainfall. While this increase was climate-driven, experts say advanced seasonal forecasting could help dam operators better anticipate such events in the future and manage reservoirs to store water more effectively.

Similarly, wind farm workers can use forecasts to schedule maintenance during low-wind periods – minimizing downtime and avoiding losses. Grid operators, too, can plan for energy spikes during heatwaves or droughts.

“We now have forecasts that span from a few seconds ahead to several months,” Mr. Bastani said. “Each one has a specific application – from immediate grid balancing to long-term investment decisions.”

Improved climate forecasting can help energy systems plan days to seasons ahead.

Artificial intelligence (AI) is lending a hand: Machine learning models trained on climate and energy data can now predict resource fluctuations with higher resolution and accuracy. These tools could help optimize when to deploy battery storage or shift energy between regions, making the system more flexible and responsive.

“These models can help operators better anticipate fluctuations in wind, rainfall, or solar radiation”, Mr. Bastain explained.

For example, two recent WMO energy mini projects illustrated how artificial intelligence can be applied in real-world renewable energy planning. In Costa Rica, the agency worked with national energy authorities to develop and implement an AI-based model for short-term wind speed forecasting. The tool is now integrated into the Costa Rican Electricity Institute’s internal energy forecasting platform, helping optimize operations at selected wind farms.

In Chile, another project focused on floating solar technology, using AI to estimate evaporation rates on reservoirs. The results, now incorporated into Chile’s official Solar Energy Explorer platform, showed that floating solar panels can reduce water evaporation by up to 85 per cent in summer, with a national average of 77 per cent.

Indeed, the promise and challenge of climate-smart renewable planning are most evident in the Global South. Africa, for instance, boasts some of the best solar potential on the planet, yet only two per cent of the world’s installed renewable capacity is found on the continent.

Why the gap? Ms. Boscolo points to a lack of data and investment.

“In many parts of the Global South, there just is not enough observational data to create accurate forecasts or make energy projects bankable,” she said. “Investors need to see reliable long-term projections. Without that, the risk is too high.”

WMO is working to improve weather and energy monitoring in underserved regions, but progress is uneven. The agency is calling for more funding for local data networks, cross-border energy planning, and climate services tailored to regional needs.

“This is not just about climate mitigation,” Ms. Boscolo added. “It is a development opportunity. Renewable energy can bring electricity to communities, drive industrial growth, and create jobs if the systems are designed right.”

Mr. Bastani sees a need for global data sharing between energy companies and climate scientists.

“There is a huge untapped potential in the data collected by the private sector… integrating historical and real-time observations from power plants – solar, wind, hydropower, even nuclear – can significantly improve weather and climate models. This is a win-win.”

Climate forecasting helps energy companies anticipate weather-driven changes in supply and demand, improving reliability and reducing risk.

Diversifying the energy portfolio to adapt

Another key action to guarantee clean energy in the near future is diversification. Relying too heavily on only one renewable source can expose countries to seasonal or long-term shifts in climate, Mr. Bastani explains.

In Europe, for example, energy planners are increasingly concerned about something called “dunkelflaute”— a period of cloudy, windless weather in winter that undermines both solar power and wind generation. This phenomenon, linked to high-pressure systems known as anticyclonic gloom, has prompted calls for more energy storage and backup power.

“A diversified mix that includes solar, wind, hydro, battery storage, and even low-carbon sources (like geothermal) is essential,” Mr. Bastani said. “Especially as extreme weather becomes more frequent.”

Into the future

As the world races towards a future powered by renewable energy, addressing the challenges posed by climate change is imperative. The volatility experienced in 2023 underscores the need for climate-smart planning and infrastructure that can withstand unpredictable shifts in weather patterns.

For renewable energy to truly fulfill its promise, the world must invest not only in expanding capacity but also in building a system that is resilient, adaptable, and informed by the best available climate science.

WMO experts Hamid Bastani and Roberta Boscolo emphasize the importance of integrating climate intelligence into energy systems to ensure their reliability and resilience. By leveraging advanced forecasting and artificial intelligence, we can better anticipate and adapt to these changes, optimizing renewable energy production and safeguarding our future.

The future of energy is not just about more wind turbines and solar panels, but also about ensuring they can withstand the very forces they are meant to mitigate.