When Greening Meets Photovoltaics: What Is Changing in Buildings, Energy and Urban Systems?

— An In-Depth Conversation with Associate Professor Rui-Dong Chang, The University of Adelaide

Across the global fields of building and energy research, a clear and ongoing shift is taking place.Greening, photovoltaics and the building itself are increasingly being re-examined within a single, integrated system — no longer treated as separate technical options, but understood as a coupled, long-term, and environmentally responsive whole.

This shift is not driven by any single breakthrough technology. Rather, it reflects a change in research perspective: from isolated performance metrics to system behaviour; from design-stage assumptions to real-world operation; from idealised models to uncertain, dynamic environments. In this edition of Academic Frontiers, Ignition Research visits the University of Adelaide to speak with Associate Professor Rui-Dong Chang, whose work focuses on the coupling between buildings, greening and energy systems. From his research perspective, we explore a more fundamental question:

How is “green building” being redefined at the academic frontier, and why are these changes worth hearing about earlier?

Associate Professor Rui-Dong Chang joined the School of Architecture and Civil Engineering at the University of Adelaide in 2020 and currently leads the Green Construction Analytics group. His research has long focused on multi-dimensional coupling across materials, energy and emissions, environmental monitoring and modelling, and optimisation-based decision-making at both building and urban scales.

Previously, he held research and teaching positions at the Solar Energy Research Institute of Singapore (SERIS), the National University of Singapore, and Bond University. He has also been recognised as one of the World’s Top 2% Most-Cited Scientists by Stanford University in both 2024 and 2025.

His team deploys a wide range of sensing and data-acquisition technologies — including UAVs equipped with LiDAR and thermal imaging, LoRaWAN IoT sensors, iPhone LiDAR and terrestrial laser scanning — to capture real-world data on energy use, microclimate, particulate matter and lighting behaviour. These datasets are combined with statistical modelling, machine learning and system dynamics methods to conduct “dynamic performance assessment” and forecasting for building and urban systems.

Through this series of conversations, Ignition Research aims to offer professionals across construction, real estate development, municipal and urban renewal, energy, landscape and greening, smart city services and sustainability consulting some practical, thought-provoking industry insights that are both actionable and easy to engage with.

Ignition Research: Your work has consistently focused on the coupling between greening, buildings and energy systems. What first led you into this area of research?

Rui-Dong Chang: Initially, my interest was not specifically in “greening” or “photovoltaics” themselves. Rather, it came from the realisation that many building performance issues are difficult to fully explain when viewed only from a fragmented perspective.

For example, energy use, thermal comfort, equipment efficiency and maintenance challenges often emerge at the same time, yet they are discussed within separate professional domains. When I began examining them within a single system, previously overlooked relationships started to become visible. These connections may not be obvious at first, but they tend to amplify over long-term operation.

Since then, my focus has been less on whether a particular technology is advanced enough, and more on how building systems actually “work together” in real-world environments.

Ignition Research: In your engagement with industry, do you sense a time lag between academic research and practical understanding?

Rui-Dong Chang: One clear issue is that many discussions still stop at the level of configuration, rather than operation.

For instance, whether a building “has photovoltaics” or “has greening” is often used as a proxy for how green it is. In research, however, we care more about whether these features remain effective over time — under different climates, at different moments, and with different patterns of use.

From an academic perspective, how long a building can actually stay in a “green” state is shaped by many real-world factors. If the complexity of the operational phase is overlooked, it becomes easy to overestimate how design solutions will perform in practice.

Ignition Research: You often refer to the concept of a “system”. In current research, where does this system-level complexity mainly show up?

Rui-Dong Chang: At the component level — for example, photovoltaic panels — technologies are becoming increasingly advanced, and our understanding of individual elements continues to deepen. However, once these advanced components interact with others in real-world settings and form a system, the outcomes are no longer simply additive. They may result in 1+1 > 2, or sometimes < 2. What matters is understanding how interactions between components can be leveraged to generate positive feedback and improve overall system performance.

For instance, greening alters the local microclimate, which in turn affects the performance of the building envelope and mechanical systems. The efficiency of photovoltaic systems depends not only on solar irradiance, but is also closely linked to microclimatic conditions. Viewed in isolation, none of these factors is especially complex; but once they overlap in real environments, they produce highly non-linear outcomes.

For this reason, many questions can no longer be judged by a single metric. They need to be understood through the behaviour of the system as a whole.

Ignition Research: Across large volumes of real-world project data, which phenomena tend to be underestimated at the design stage?

Rui-Dong Chang: In my view, the most commonly underestimated factor is the effect of time.

Many design assumptions implicitly treat system performance as stable. In actual operation, however, seasonal changes, shifts in usage patterns and differences in maintenance gradually reshape system conditions. These changes may not be obvious in the short term, but over a period of years they can significantly affect both performance and cost.

This is why academic research is increasingly focused on long-term, continuous datasets and on forecasting future behaviour. Only by doing so can we see the true trajectory of how projects evolve after implementation.

Ignition Research: This is a topic widely discussed in industry. On one hand, increasing greening is seen as a way to mitigate the urban heat island effect; on the other, many residents worry that excessive vegetation can be difficult to maintain. How do you see the current debate around this issue?

Rui-Dong Chang: The impact of greening on building energy use is highly complex. It depends on many factors, including the local climate zone, vegetation height, distance from the building, and the choice of building materials and components.

For example, in summer, shading from vegetation and plant evapotranspiration reduce heat gain to the building, lowering cooling loads and energy consumption. In winter, however, evergreen trees may block valuable solar access, increasing heating demand and therefore energy use. Over the course of a year, whether vegetation has a net positive or negative impact can only be determined through detailed energy simulation.

In principle, greening modifies the outdoor microclimate — including temperature, humidity and wind conditions — which in turn affects building energy performance. The same greening strategy may significantly increase energy use in cold regions, yet become an optimal solution in hot and humid climates. Context matters, and there is no one-size-fits-all answer.

In practice, the choice of greening strategies must consider not only energy impacts, but also other risk factors such as ease of maintenance and whether certain plants may trigger severe allergies.

For this reason, academic discussions tend to focus on identifying the conditions under which overall performance is positive, and the situations in which risks are likely to be amplified.

Ignition Research: From a research frontier perspective, which factors are likely to have a growing impact on building and energy systems in the years ahead?

Rui-Dong Chang:Several directions are becoming increasingly important.

First, system resilience under extreme climate conditions. Second, managing uncertainty arising from multi-system coupling. Third, how data can form a feedback loop between design and operation.

All of these point to the same trend: buildings are no longer one-off products delivered at completion, but long-term systems that continue to operate, adapt and evolve over time.

Ignition Research: As a final question, from your perspective, why is it important for companies to follow academic research that is still evolving?

Rui-Dong Chang: Because once a direction becomes fully mature and standardised, it often no longer offers much room for exploration.

The value of academic research lies in revealing complexity and potential risks in advance. Even if companies choose not to act immediately, understanding these developments can help them make more resilient decisions in the future, rather than reacting passively to change.

In this conversation, Associate Professor Rui-Dong Chang did not offer a checklist of ready-made answers. What emerges instead is a broader shift in perspective: buildings, greening and energy are being brought back into a real, long-term and uncertainty-rich operational context. They are no longer viewed as isolated design choices, but as evolving systems embedded in complex environments.

At Ignition Research, we believe the value of academic frontiers does not lie in prescribing how every project should be delivered. Rather, it lies in providing companies with an earlier cognitive reference point — a way to see change before it becomes simplified into standards or reduced to labels. When directions are still unfolding and trends have not yet been fixed, those who are willing to engage with complexity in advance often gain greater room to think, decide and act.

Frequently asked questions

Q: Why are greening, photovoltaics and buildings now being studied as one integrated system instead of separately? A: The article describes a shift in building and energy research where greening, photovoltaics and the building are re-examined as a single, coupled, long-term system rather than separate technical options. It says this is driven not by one breakthrough technology but by a change in perspective — from isolated performance metrics to system behaviour, and from design-stage assumptions to real-world operation.

Q: Who is Associate Professor Rui-Dong Chang at the University of Adelaide and what does he research? A: According to the article, Rui-Dong Chang joined the University of Adelaide's School of Architecture and Civil Engineering in 2020 and leads the Green Construction Analytics group, focusing on the coupling of materials, energy and emissions, environmental monitoring and modelling, and optimisation-based decision-making at building and urban scales. The article notes he was recognised by Stanford University as one of the World's Top 2% Most-Cited Scientists in both 2024 and 2025, and previously held positions at SERIS, the National University of Singapore and Bond University.

Q: What technologies does Chang's team use to collect real-world data on buildings and urban systems? A: The article says the team deploys UAVs equipped with LiDAR and thermal imaging, LoRaWAN IoT sensors, iPhone LiDAR and terrestrial laser scanning to capture data on energy use, microclimate, particulate matter and lighting behaviour. These datasets are then combined with statistical modelling, machine learning and system dynamics methods for what it calls dynamic performance assessment and forecasting.

Q: What gap does the article identify between how industry and researchers understand green buildings? A: The article suggests many industry discussions still stop at the level of configuration rather than operation — for example, treating whether a building simply 'has photovoltaics' or 'has greening' as the key point. Chang's emphasis is instead on how building systems actually work together in real-world environments over long-term operation. The article states it offers industry observations and forward-looking perspectives only and does not constitute any investment or engineering advice.