UNSW study finds bushfire smoke cuts solar output by 70% near fires

A new study from the University of New South Wales (UNSW) indicates that bushfire smoke can reduce solar electricity generation by up to 70% in areas near active fires. The research team analyzed historical weather and satellite data to assess how smoke particles affect both panel output and temperatures.

Quantified Output Losses

UNSW researchers quantified the generation impact of two major Australian fire events, revealing a sharp decline in solar output as distance from hotspots decreases.

Fire Event	Distance from Hotspots	Generation Drop
Black Summer	Within 50 km	Up to 70%
Black Summer	Over 150 km	Around 40%
Black Saturday	Near hotspots	18%
Black Saturday	Over 100 km	4% to 10%

During the Black Summer fires, installations within 50 km of hotspots experienced losses reaching 70%, while those situated more than 150 km away still saw output fall by approximately 40%. In contrast, the Black Saturday event resulted in an 18% drop near the fires, tapering to a 4–10% reduction for sites located beyond 100 km.

Thermal and Physical Mechanisms

Beyond reduced sunlight, smoke particles settle on panel surfaces, creating localized hotspots that drive module temperatures 10–20°C above climatological norms.

Operational Adaptation Strategies

• Dr Shukla Poddar, Postdoctoral Researcher at the School of Photovoltaics and Renewable Energy Engineering, UNSW Sydney, recommends investigating smoke trajectory modelling to understand how long and far particles travel.
• Operators can adapt to potential impacts by adjusting panel angles where appropriate and recognizing that additional cleaning may be necessary.
• Key mitigation strategies include better smoke forecasting, frequent inspections, cleaning, and panel angle adjustments.

Upon receiving alerts that a solar farm faces potential impact, operators can deploy targeted mitigation tactics. This includes modifying panel angles where suitable and acknowledging that extra cleaning might be essential.

Improved smoke forecasting facilitates earlier readiness, whereas regular inspections assist in determining when cleaning is required.

International Smoke Dispersion and Site Selection Frameworks

Dr Shukla Poddar notes that extreme bushfires are becoming more frequent and intense in regions including California and southern Europe. She cites instances where smoke from California’s 2020 wildfires reached Europe, while emissions from Spain’s 2025 fires travelled as far as the UK and northwestern Europe. Although the current study focuses on two Australian extreme events, the researchers state the same method and analysis can be applied to other parts of the world.

The paper explicitly recommends combining bushfire information, wind patterns, and smoke-trajectory modelling to predict which solar farms are likely affected. This framework serves as a pre-feasibility assessment for site selection, allowing developers to examine prevailing wind directions and likely smoke pathways. It also aids in understanding optimal operational strategies for existing farms in proximity to hotspots or affected by aerosol dispersion. The study emphasizes that weather forecasts currently help operators anticipate high temperatures and strong winds, but a similar system for smoke would provide advanced warning of airborne particles heading toward facilities.

What to watch

Future site selection will increasingly rely on bushfire history, wind patterns, and smoke pathways during pre-feasibility assessments. However, the study’s findings are based on modelled estimates rather than specific measurements from individual solar farms.