UMNE SCI Studio: Energy Transition and the Future of Solar Photovoltaics
In the first half of 2025, solar and wind covered 109% of the global growth in electricity demand — renewable sources surpassed coal for the first time in their share of global electricity generation. But where are the limits of this technology?
This video is dedicated to the global energy landscape — from China’s mega capacity expansion and Africa’s solar surge to Pakistan’s breakthrough of 25% — and to perovskite–silicon tandem cells as the most significant technological advancement in photovoltaics over the past decade. Laboratory efficiency of these cells already exceeds 34%, but the path to commercialization still passes through the unresolved issue of material stability. The video presents empirical data, explains the physics of the two-layer system, and raises the question that defines the energy transition: can the growth rate of renewable energy keep pace with CO₂ emissions, which reached a record 38.1 billion tonnes in 2025?
Energy Transition 2025
Since the Industrial Revolution, the global economy has relied on fossil fuels; coal, oil, and gas form the infrastructure of the modern world — and almost every time electricity demand increased, fossil power plants increased as well.
According to an analysis by the energy think tank Ember (UK), in the first half of 2025 global electricity consumption increased by 369 TWh, while solar and wind together added 403 TWh — covering 109% of that growth, which led to a slight decline in electricity generation from fossil fuels. At the same time, renewable electricity sources surpassed coal for the first time in their share of global electricity generation — 34.3% compared to 33.1%.
In the first half of 2025, approximately 380 GW of new solar capacity was commissioned globally. China added around 256 GW — nearly two-thirds of the total increase — and according to analysts from CREA (Centre for Research on Energy and Clean Air, Helsinki), this pace corresponds to building the equivalent of about 20 football fields of solar panels every hour. The total installed capacity of wind turbines and solar panels in China reached 1,482 GW, surpassing the capacity of thermal power plants. However, in the first quarter of 2025 wind and solar accounted for 22.5% of electricity delivered to consumers, because installed capacity and actual generation are not the same.
The growth is not limited to China: solar panel imports into African countries increased by about 60% between June 2024 and June 2025; Pakistan covered 25.3% of its public electricity supply with solar energy in the first four months of 2025; and the International Energy Agency (IEA) projects an increase in global renewable electricity capacity of about 4,600 GW between 2025 and 2030, with roughly 80% coming from solar power.
On the technological front, a new generation of photovoltaics has emerged — perovskite–silicon tandem solar cells. Almost all commercial solar panels are made of silicon, which converts only part of the solar spectrum into electricity; the rest either passes through the cell or is lost as heat. Perovskite is a crystalline material whose composition can be tuned to more efficiently absorb wavelengths that silicon uses less effectively. In a two-layer configuration, perovskite on top captures the high-energy portion of the spectrum, while silicon beneath captures the lower-energy part, together covering a broader range of sunlight. Typical commercial silicon panels today reach around 20–22% efficiency, while in controlled laboratory conditions perovskite–silicon tandems have achieved an efficiency of 34.85% (NREL). The first commercial steps have already begun, but large-scale deployment still depends on long-term material stability, standardized industrial production, and reliable encapsulation.
According to the Global Carbon Project, global fossil CO₂ emissions will reach a record 38.1 billion tonnes in 2025. The United Nations Environment Programme (UNEP) and the Intergovernmental Panel on Climate Change (IPCC) warn that existing policies and commitments are not sufficient to keep global warming below 1.5°C without overshoot.
SOURCES
Ember (2025a). Global Electricity Mid-Year Insights 2025. Ember (UK), 7 October 2025.
Ember (2025b). Global solar installations surge 64% in first half of 2025. Ember (UK), 2 September 2025.
Ember (2025c). The first evidence of a take-off in solar in Africa. Ember (UK), 26 August 2025.
International Energy Agency (IEA) (2025). Renewables 2025: Analysis and forecasts to 2030. Paris: IEA.
Reuters (2025a). China’s wind and solar capacity exceeds thermal power for first time, energy regulator says. Reuters, 25 April 2025.
Reuters (2025b). Pakistan’s solar surge lifts it into rarefied 25% club. Reuters, 17 June 2025.
National Renewable Energy Laboratory (NREL) (n.d.). Best Research-Cell Efficiencies (PV chart). Golden, CO: NREL. Accessed: 24 Feb 2026.
Friedlingstein, P. et al. (2025). Global Carbon Budget 2025 (living data update) [preprint]. Earth System Science Data Discussions. https://doi.org/10.5194/essd-2025-659
Global Carbon Project (2025). Fossil fuel CO₂ emissions hit record high in 2025 (press release/summary), 13 November 2025.
United Nations Environment Programme (UNEP) (2025). Emissions Gap Report 2025: Off target – Continued collective inaction puts global temperature goal at risk. Nairobi: UNEP. https://doi.org/10.59117/20.500.11822/48854
Intergovernmental Panel on Climate Change (IPCC) (2018). Global Warming of 1.5°C: An IPCC Special Report. Geneva: IPCC.