As sustainability takes centre stage in the built environment, lighting design has emerged as a critical element in creating green buildings, according to the Illumination Engineering Society of South Africa (IESSA).
More than simply illuminating spaces, lighting affects energy use, occupant comfort, and environmental impact. In South Africa, where power constraints and climate challenges demand smarter solutions, eco-friendly lighting design is both a necessity and an opportunity.
This blog explores what defines a green building, provides a guide to eco-friendly lighting, examines the impact of design on green building performance, and explains what the Green Star South Africa certification means for the local industry.
What makes a green building?
A green building is designed, constructed, and operated to reduce negative impacts on the environment while enhancing the health and comfort of occupants.
Characteristics typically include:
- Energy efficiency: Minimising electricity consumption in areas like HVAC and lighting.
- Water efficiency: Incorporating rainwater harvesting, greywater reuse, and efficient fixtures.
- Sustainable materials: Using recycled, locally sourced, or low-carbon building products.
- Indoor environmental quality: Improving air quality, daylight access, and thermal comfort.
- Site sustainability: Protecting biodiversity and managing resources responsibly.
In South Africa, the Green Building Council South Africa (GBCSA) has been instrumental in promoting sustainability through its Green Star SA rating tools, which set benchmarks for best practice and world leadership.
Lighting is a powerful driver within this framework, as it directly impacts both energy performance and indoor environmental quality.
A guide to eco-friendly lighting
Designing lighting systems for green buildings requires a balance between efficiency, user comfort, and adaptability. Below are key strategies for eco-friendly lighting:
- Harness natural light
Daylighting strategies, such as skylights, large windows, and light shelves, reduce reliance on artificial light. Coupled with daylight sensors, lighting systems can automatically adjust output to save energy.
- Choose high-efficiency fixtures
LEDs have become the global standard for energy-efficient lighting, offering long lifespans, excellent light quality, and reduced maintenance. Where possible, select fixtures with recycled content or modular components for sustainability across the product life cycle.
- Use smart controls
- Occupancy sensors switch off lights in unused spaces.
- Dimming systems allow for tailored light levels.
- Time scheduling and zoning prevent over-lighting outside of working hours.
- Networked control systems integrate with building management, ensuring optimal use, and monitoring.
- Design for purpose
Lighting should be matched to the task, avoiding over-illumination that wastes energy. Layered design (ambient, task, and accent lighting) ensures flexibility and comfort.
- Plan for maintenance and longevity
Systems with replaceable parts, modular drivers, and recycling programs help extend product life and reduce waste. Long-term monitoring also ensures sustained efficiency.
How lighting design impacts green buildings
Lighting design doesn’t just save electricity; it shapes how a building performs and how people experience it.
- Energy and emissions: Well-designed systems reduce operational costs and greenhouse gas emissions.
- Occupant well-being: Balanced lighting supports visual comfort and can positively influence mood and productivity.
- Thermal load: Efficient lighting reduces excess heat, lowering HVAC demand.
- Flexibility: Zoning and smart controls allow spaces to adapt to changing uses.
- Certification points: Thoughtful design contributes to achieving credits in rating systems like Green Star SA, particularly under the energy and indoor environmental quality categories.
What is Green Star South Africa?
Green Star SA is South Africa’s sustainability rating system for buildings, adapted from the Green Star system in Australia. Managed by the GBCSA, it provides a recognised framework for assessing building projects.
- Certification levels: 4-Star (Best Practice), 5-Star (South African Excellence), and 6-Star (World Leadership).
- Assessment categories: Energy, indoor environment, water, materials, land use, emissions, and more.
- Relevance to lighting: Energy-efficient lighting systems and smart controls help secure credits, while good daylighting and glare control contribute to indoor environment scores.
More recently, GBCSA have introduced The Green Star 2.0 (V2) rating tool, which is a more comprehensive system that rates new and major refurbished buildings on a range of environmental, social, and governance (ESG) factors, including energy, water, materials, and social equity. This V2 update incorporates newer science and best practices to encourage more holistic and sustainable buildings across different typologies, like offices and schools.
Prominent examples of Green Star SA projects include the Portside Tower in Cape Town, which achieved a 5-Star rating and uses predominantly LED lighting.
