Grazing lighting: why is adaptive street lighting the future?

Street<strong>Lighting</strong> | LED<strong>Lighting</strong> | Grazing<strong>Lighting</strong> | Architectural<strong>Lighting</strong>

StreetLighting | LEDLighting | GrazingLighting | ArchitecturalLighting

Grazing lighting.

Why is adaptive street lighting the future?

It meets the visual needs of road users, considering different traffic volumes during the night or in varying weather conditions. It also offers reduced energy consumption and potential
environmental improvements.

For example, older users have different visual capabilities (a 70-year-old man has 66% visual acuity compared to a 25-year-old), react differently to colour rendering index (CRI), and are more affected by glare.

The technical standard recognize that a lighting system is not static but dynamic, suggesting variables that may require an adaptive response over time. Until now, street luminaires have only been able to address some of these variables.

Adaptive lighting in traditional systems relies on dimming and sometimes changing the colour temperature.

SIDEis introduces a new level of adaptability and flexibility: dynamic optical distribution.<br>
This is a powerful tool for improving our solutions and addressing newer and broader
challenges.

SIDEis introduces a new level of adaptability and flexibility: dynamic optical distribution.
This is a powerful tool for improving our solutions and addressing newer and broader challenges.

Adaptive Lighting on Asphalt

Asphalt is the most important element in road lighting since everything depends on its ability to reflect light towards the driver's eyes.

It’s essential to understand not just how much light is reflected, but also how it reflects from different angles. These conditions are not stable but vary depending on atmospheric conditions and the asphalt’s deterioration (porous asphalt is generally darker and less reflective).

A change in the reflective surface is a significant shift in road lighting and cannot be solved with current products existing on the market.
In addition to asphalt, luminaire failures can create unpredictable scenarios, severely compromising lighting uniformity.
In a traditional installation with a 30-meter spacing between luminaires, alternating failures create a pattern of high and low luminance, causing disabling glare and reducing visibility.

A SIDEis luminaire, capable of optically adapting to cover the gaps of failed ones, provides a solution to an otherwise unsolvable problem. Other examples include uphill roads, where certain angles become critical for drivers, requiring optical customization on-site. A customizable, site-selectable photometric distribution is a powerful tool for solving unpredictable problems during the design phase.

Adverse Weather Conditions

Adverse weather conditions affect how the drivers perceive the road. Wet asphalt reflects light differently and less uniformly than dry asphalt. Air humidity and pollution create a physical barrier to light, while fog benefits from grazing lighting systems.

In terms of road visibility and detecting objects on the road:

SIDEis lighting is emitted below the driver’s level, reducing upward scattering.
Backscattered and forward-scattered light is focused transversely rather than longitudinally, reducing diffused light toward the driver.
Luminaires installed about 80 cm from the road surface and spaced a few meters apart provide significant optical guidance.
In foggy conditions, a pro-beam optical distribution reduces the scattering effect, allowing for better light adjustment.
The luminaire’s intensity distribution is adjusted for both energy-saving and adverse weather conditions, reducing diffused light toward the driver normal situations (energy saving) and adverse weather conditions (reducing the fraction of diffused light towards the driver).

Intrusive Light and Light Pollution

What is intrusive light?

Intrusive light is defined as external light that, due to its intensity, direction, or spectral characteristics, causes discomfort, distractions, or reduces visibility (CIE 115).

For street lighting, only two effects are commonly discussed: the impact on residents and on astronomical observations. Light from street lighting can be intrusive when it enters areas like bedrooms.

Illuminating vertical surfaces, such as windows, can cause discomfort or distraction.
The luminance level of the luminaire in a given direction can also indicate this effect.
SIDEis offers precise, effective street lighting with minimal light spillage. Mounted at low heights, the light remains at horizontal angles, and barriers like guard rails create natural boundaries, reducing wasted light.

Drone photos of traditional pole-mounted versus grazing luminaires clearly illustrate the reduction in light pollution with SIDEis.