Many UK households exhibit inefficient energy performance. Wasted energy negatively impacts the environment and causes higher energy bills, which have become major concerns in the UK’s current economic climate.

A major source of wasted energy comes from outdated lighting and inadequate lighting design. Many UK residential properties still rely on compact fluorescent lamp (CFL) technology, which became widespread in the early 2000s. While light-emitting diode (LED) systems offer a more energy-efficient and higher-performing alternative, adoption has been limited by factors such as cost, lack of awareness, and perceived installation complexity.

A new study published in the Open Access journal Buildings provides a simulation-based framework that demonstrates how transitioning from CFL-based lighting to LED systems can significantly improve both energy performance and compliance with recommended illumination standards in UK housing.

The work establishes a reproducible data-driven approach that aligns with the UK’s aim of conserving fuel and power while contributing to knowledge that can be used globally to bridge human-centric lighting design and energy performance optimisation. As stated by lead author Dr. Jawed Qureshi:

“If we take a more thoughtful approach to lighting design, we can deliver energy savings, improve comfort and support wider sustainability goals all at once.”

The importance of residential lighting

Residential lighting plays a vital role in creating comfortable, functional, and energy-efficient living environments. However, it has also been shown to directly affect human health and biological functioning.

Circadian rhythm is an innate biological process present in most organisms that governs various physiological processes over a 24-hour period. It plays a crucial role in regulating sleep-wake patterns, hormone release and metabolism. Exposure to bright, blue-enriched light during the day can promote wakefulness, while warmer light in the evening encourages relaxation and is beneficial for sleep hygiene.

Although this study does not directly assess the impact of lighting on health or wellbeing, it acknowledges these principles as important considerations in residential lighting design.

Instead, the research focused on technical lighting performance and energy efficiency. Lighting was simulated across twenty, one-bedroom flats, comparing existing, manually designed CFL schemes with optimised LED designs created in DIALux Evo. Using manufacturer data on bulb properties, the software determined optimal light placements required to achieve target illuminance levels to provide comfortable living conditions. Energy consumption was then compared across both scenarios to assess the impact of improved lighting design.

Overall, the research highlights how simulation-based lighting design can help tackle sustainability challenges in housing. By demonstrating that energy efficiency improvements can be achieved without compromising lighting quality, the study provides valuable insights for future residential standards in the UK and around the world. As Dr. Jawed Qureshi explains:

“What this research shows is that by combining smarter design with the right technology, we can reduce energy use and improve how spaces feel at the same time. It is not just about switching to LEDs. It is about using them intelligently.”

Effects of smarter lighting on energy consumption

Two key trends emerged across the twenty lighting scenarios:

• DIALux-optimised designs reduced energy consumption by between 1% and 30% in eighteen of the twenty scenarios.
• DIALux-based designs increased average illuminance across all room types, improving compliance with recommended lighting levels.

Importantly, the two scenarios where energy consumption increased marginally reflect cases where additional lights were needed to reach required illuminance levels. This highlights that simulation-based optimisation does not always guarantee energy reduction and that its value lies in simultaneously optimising both energy performance and lighting quality.

The observed energy savings arose from two key factors:

• Switch from CFL to LED: LED lights offer higher luminous efficacy, delivering more light for less energy input.
• Simulation-driven design: Enables precise spatial modelling of lighting layouts, optimising luminaire placement and reducing the number of fittings required to meet target illuminance levels.

Overall, these findings reinforce the value of transitioning from manually designed CFL systems to an integrated LED-plus-simulation workflow for residential buildings, supporting both energy reduction and improved lighting compliance. The framework also provides a foundation for future research and potential policy application in housing design.

Designing energy efficient living spaces for the future

The use of software such as DIALux Evo represents an important step forward in residential design, offering tools that improve living conditions while reducing energy consumption. As the UK continues its transition towards Net Zero targets, such digital approaches are becoming increasingly central to the design of efficient and sustainable homes.

This study demonstrates that an integrated LED-plus-simulation workflow can deliver both improved lighting quality and an average energy reduction of 15.3% across diverse residential layouts. Its successful application across twenty spaces highlights its potential scalability for both retrofit and new-build housing strategies.

From a practical standpoint, simulation-based design reduces reliance on time-intensive manual calculations and enables more precise optimisation of lighting layouts. In the future, integration with broader building systems, such as heating and ventilation, could further enhance whole-building energy performance.

However, several limitations should be acknowledged:

• The exclusion of daylight effects may overestimate energy savings.
• Dynamic lighting controls were not considered, limiting time-based realism.
• The study is restricted to one-bedroom flats, reducing generalisability.

Despite these limitations, the findings demonstrate that simulation-led lighting design shows great promise as a scalable and effective tool for improving energy usage in residential housing. This aligns with the United Nations’ goal for sustainable consumption. As digital design technologies continue to evolve, their integration into policy and building design are likely to play an increasingly important role in providing homes that are more energy efficient.

More studies on energy-efficient buildings and smart buildings can be found across the Open Access journals Sustainability and Buildings.

Alternatively, you can access the full MDPI journal list here.