Lighting calculations

Lighting calculations are a critical aspect of the design and evaluation of lighting systems in various applications, including architecture, interior design, industrial settings, and outdoor spaces.

Lighting calculations involve the use of mathematical and computational methods to determine and optimize various aspects of lighting, such as illuminance, luminance, and light distribution. Lighting professionals, such as lighting designers and engineers, rely on these calculations to ensure that the lighting in a space meets specific requirements and standards.

As Emanuel Guillen a lighting consultant IHO Espacios in Mexico City explains,

¨ Light can highlight or dim your project, It's important to hire a lighting specialist for your project design, someone who knows how light behaves well and is an expert in how to handle it.

Let's remember that the main objective of adding light to our architectural projects is to "SEE" and sometimes the projects themselves do not provide us with adequate natural lighting and we need the support of artificial lighting...

Nowadays there are several software systems that help us with the calculation of light in projects. These are 95% accurate in light emulation depending on how the luminaire is configured.¨

What are the key areas of Lighting calculation and their importance in the lighting industry?

1. Illuminance: Illuminance is the measure of the amount of light that falls on a surface. It is typically expressed in units of lux (lx) or foot-candles (fc). Lighting calculations help determine the required illuminance levels for different tasks or activities within a space. For example, an office workspace may require a certain minimum illuminance level for comfortable and productive work.
2. Luminance: Luminance refers to the brightness of a surface as perceived by the human eye. It is typically measured in units of candles per square meter (cd/m²). Lighting calculations can be used to assess and control the luminance of various surfaces and objects in a space to ensure visual comfort and safety.
3. Light Distribution: Lighting calculations help professionals analyze how light is distributed within a space. This includes the intensity and uniformity of light across the area. Lighting designers can use this information to position luminaires (light fixtures) effectively and ensure that lighting meets the required standards and aesthetics.
4. Glare Analysis: Glare is excessive brightness or discomfort caused by intense light sources. Lighting calculations can help identify potential glare issues and allow professionals to implement strategies to minimize glare, which is crucial for user comfort and safety.
5. Energy Efficiency: Lighting professionals use calculations to design energy-efficient lighting systems. This involves selecting appropriate lighting sources (e.g., LED, fluorescent, incandescent), optimizing the number and placement of luminaires, and considering lighting controls to reduce energy consumption while maintaining required lighting levels.
6. Compliance with Standards: Lighting professionals must adhere to lighting standards and regulations that define minimum requirements for illuminance, color temperature, color rendering, and more. Lighting calculations help ensure compliance with these standards.
7. Rendering: Lighting calculations can be used to create 3D visualizations and renderings of a space, allowing clients and stakeholders to visualize how the lighting design will appear and make informed decisions.
8. Life Cycle Cost Analysis: Lighting professionals may conduct life cycle cost analyses to evaluate the long-term costs of a lighting system, including initial installation, maintenance, and energy expenses. This information helps in making cost-effective decisions.
9. Daylighting: In architectural and sustainable design, lighting calculations can assess how natural daylight interacts with artificial lighting to optimize energy efficiency and create a pleasant indoor environment.
10. Retrofitting and Upgrades: Lighting calculations can aid in assessing the feasibility and benefits of retrofitting existing lighting systems with more energy-efficient options or making upgrades to meet changing lighting needs.

¨Technology has advanced a lot in recent years, a scientific calculation of lighting well done and carried out by a certified professional will reduce the risks considerably.¨

¨It is important to be aware of everything that can affect or influence the calculation, from highly reflective finishes such as very shiny floors or bar materials, as well as materials that absorb light, do not reflect it and drown the space, such as carpets, woods and textiles. Each luminaire has its own flux, aperture angle, materials it is made of and its own diffusers, all of which have to be referenced in the software for the calculation to be accurate. ¨ Emanuel Guillen

In summary, lighting calculations are a fundamental tool for lighting professionals to design, analyze, and optimize lighting systems for a wide range of applications. They play a crucial role in ensuring that lighting in a space is functional, energy-efficient, compliant with standards, and aesthetically pleasing while also meeting the needs and preferences of the users. The benefits of hiring a professional for calculating your lighting requirements and many and depends on the nature of your project.