Solar Glint and Glare occurs when sunlight is reflected from a surface, toward light-sensitive receptors
The terms ‘Glint’ and ‘Glare’ are defined as follows:
- Glint - a momentary flash of bright light
- Glare - a continuous source of bright light
Glint and glare effects can present a hazard to light-sensitive receptors as they can result in an after-image (a visual illusion where an image persists after exposure to the original image has ceased). This can be a hazard for moving receptors such as road, rail or air traffic. Glare effects can also affect nearby communities through impacts on residential amenity.
A glint and glare assessment is an investigation into the expected glint and glare hazard of a given development (typically, but not exclusively solar PV projects) . Through detailed modelling, the assessment calculates the times and duration of glint and glare effects for a given location, based upon:
- The solar panels position, tilt angle and azimuth (the direction the reflector is facing, relative to north)
- The position of nearby light-sensitive receptors. This can include individual point receptors such as houses, or moving receptors such as road traffic, or aircraft following a specific flight path
- The sun’s path across the sky (elevation and azimuth)
- Local topography, including reflector and receptor heights above sea level
The assessment considers whether glint and glare effects could be dangerous for road / rail / air traffic or constitute an unreasonable adverse impact for neighbours. Where necessary, the assessment can also contain recommendations for mitigation such as additional screening, the implementation of anti-glare solar panels or modifications to the reflectors’ tilt or azimuth angle.
Our technical experts at Metrica are able to undertake in-house glint and glare assessments to identify potential impacts on light-sensitive receptors due to solar PV developments, from single dwelling roof-mounted panels to large scale Nationally Significant Infrastructure Projects (NSIPs). Our concise, pragmatic approach ensures any potential significant impacts are identified, whilst remaining cost-effective for developments of all scales.