Power grid issues are the leading cause of blackouts

This briefing by Zero Carbon Analytics examines the causes of power blackouts, arguing that failures in network infrastructure, human error, and extreme weather are the primary drivers rather than renewable energy generation. It highlights a significant global investment gap in grid infrastructure, which the IEA warns could become the "weak link" in the energy transition.

• Blackouts are typically caused by a combination of interrelated factors rather than a single event. The most frequent initial causes include infrastructure failure (particularly transmission line faults), human error—such as failing to implement protection standards—and extreme weather that damages infrastructure.
• Contrary to common misconceptions, variable renewables are not the primary cause of blackouts. Analysis of 20 major events shows they are overwhelmingly driven by network infrastructure failures, which then cause various types of power plants to go offline.
• Decarbonised electricity systems can enhance grid security through adequacy, operational security, and resilience. This is achieved via energy storage to manage variable output, interconnections between countries to share resources, decentralisation to reduce single points of failure, and demand response to avoid peak loads.
• Renewable energy and storage technologies can support 'black starts' to restart grids after a blackout. For example, ScottishPower demonstrated that wind power using grid-forming technology can regulate voltage and frequency to stabilise or restart a transmission network.
• Grid investment needs are driven by four main factors: the integration of new renewable generation in new locations, the replacement of ageing assets from the mid-20th century, rising global electricity demand (driven by electrification, population growth, and data centres), and the transition to digitalised smart grids.
• According to Bloomberg New Energy Finance (BNEF) Net Zero scenario, the deployment of renewable generation is the largest driver of grid investment at 35%, followed by the replacement of ageing assets at 30%. Factors unrelated to decarbonisation account for over 50% of projected investment through 2050.
• There is a critical gap in grid investment. The IEA reports that while USD 390 billion was invested in grids in 2024, USD 600 billion annually is required by 2030. Consequently, the IEA warns that grids risk becoming the "weak link" and represent "one of the biggest energy security risks".
• Following a blackout in April 2025 on the Iberian Peninsula, the Spanish government announced an additional EUR 750 investment to increase grid resilience.

APA

Woodman, B. (2025). Power grid issues are the leading cause of blackouts. Zero Carbon Analytics. https://zerocarbon-analytics.org/energy/power-grid-issues-are-the-leading-cause-of-blackouts/

Chicago

Woodman, Bridget. Power grid issues are the leading cause of blackouts. Zero Carbon Analytics, 2025. https://zerocarbon-analytics.org/energy/power-grid-issues-are-the-leading-cause-of-blackouts/.

Wikipedia

{{cite report |last1=Woodman |first1=Bridget |title=Power grid issues are the leading cause of blackouts |publisher=Zero Carbon Analytics |date=23 September 2025 |url=https://zerocarbon-analytics.org/energy/power-grid-issues-are-the-leading-cause-of-blackouts/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{woodman2025power, author = {Woodman, Bridget}, title = {{Power grid issues are the leading cause of blackouts}}, institution = {Zero Carbon Analytics}, year = {2025}, month = sep, url = {https://zerocarbon-analytics.org/energy/power-grid-issues-are-the-leading-cause-of-blackouts/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }