A new study from the University of Surrey in the UK shows that solar energy has officially become the world’s most economical source of electricity. In areas with excellent sunlight, the cost of generating electricity has fallen to a record low of just £0.02 per kilowatt-hour, significantly lower than traditional coal and natural gas, and also outperforming other renewable energy sources like wind power. This milestone signifies a fundamental shift in the global energy landscape, with solar photovoltaic technology becoming a core engine driving the world’s transition to clean energy. The research findings have been published in the prestigious journal Energy & Environmental Materials.
The report indicates that even in countries like the UK, located at 50 degrees north latitude and not particularly blessed with abundant sunlight, solar energy has become the most economical option for large-scale power generation. This completely dispels the conventional wisdom that solar energy is only suitable for areas with abundant sunlight.
This transformation is driven by decades of continuous innovation in photovoltaic technology and the cost benefits brought about by large-scale production. Recent news reports indicate that global installed solar capacity will reach a historic 1.5 terawatts in 2024, doubling the 2020 level. This scale of installed capacity is sufficient to meet the electricity needs of hundreds of millions of households, marking the transformation of solar energy from an alternative energy source into a cornerstone of a resilient, low-carbon energy system.
The intermittent nature of solar power generation was once a major bottleneck hindering its large-scale adoption. However, this situation is changing dramatically with the rapid advancement of energy storage technology. The report highlights that lithium-ion battery prices have plummeted by 89% since 2010, making the overall cost of a “solar-plus-storage” hybrid system competitive with natural gas peaker power plants.
This system, combining photovoltaic panels with large-scale battery storage, has become a standard feature of new energy projects worldwide. It stores excess energy during periods of abundant sunshine and releases it on demand at night or during peak demand, transforming previously volatile solar power into a dispatchable, controllable, and stable source of electricity. This transformation not only ensures local power reliability but also effectively participates in grid peak load regulation, providing critical support for maintaining overall power system balance.
With the rapid increase in the share of renewable energy in the energy mix, safely and efficiently integrating volatile solar power into the existing grid has become a pressing challenge. The International Energy Agency (IEA) clearly states in its annual report that addressing this challenge requires multi-faceted technological collaboration. Smart grids, through advanced sensing, communication, and control technologies, enable precise management of power flows. Artificial intelligence forecasting can significantly improve the accuracy of power generation and load forecasts, providing decision-making support for grid dispatch. Strengthening regional grid interconnection will enable energy complementarity and coordination on a wider scale.
At the same time, innovations in materials science are opening up a second growth curve for the solar energy industry. Perovskite solar cells are considered the next generation of photovoltaic technology. Compared to traditional silicon-based cells, perovskite cells offer not only lower manufacturing costs but also flexibility and translucency. They also have the potential to increase power generation per unit area by up to 50% by improving photoelectric conversion efficiency without requiring additional land. This means that in the future, even windows and exterior walls of buildings could become power generators, greatly expanding the application scenarios of solar energy.
The research team emphasized in the report that while market forces and the latest technological breakthroughs have paved the way for the development of solar energy, long-term and stable policy support is crucial for sustainable and healthy industrial development. Clear policy guidance and market signals can effectively stimulate the private sector’s investment enthusiasm and technological innovation vitality, and guide resources to the most critical R&D and infrastructure areas.
