The S-WORD: Defining Sustainability


Today, people argue, the power of the word ‘sustainability’ has been diluted due to overuse. What began as a noble ideal has been reduced to a mere buzzword. We sat down with some of our professors to understand how ‘sustainability’ is more than hype for them and their research.


Professor I. Daniel Posen
Research Focus: Providing system-scale environmental sustainability analysis for policy development

Large-scale systems are inherently complex. When holistically evaluating the ‘sustainability’ of a system a broad range of environmental, societal and economic metrics compound the matter. Naturally, a professor with such a research focus has a complicated relationship with the word ‘sustainability’. Riddled with over-hyped products, under-delivering theories and overall ‘greenwashing’, Professor Posen believes the discourse is weak.  He particularly notices the current lack of numerical definition.

Posen’s research exists at the intersection of engineering, environmental science, economics and public policy. His cross-discipline approach engenders a complete evaluation of all ‘sustainability’ efforts. It is with this integrated analysis that Professor Posen seeks to inform future system designs yielding greener outcomes.

Success in his quantitative analysis for policy development depends on capturing all factors, inputs and circumstances. The accuracy and availability of data, the consistency of modelling efforts across fields and the incorporation of nascent technologies are some challenges he must address. The variables are numerous, nuanced and involve advanced statistical analysis. Iterations are necessary to provide confidence ranges and uncertainty measurements to help craft policies.

Appropriately, Posen views ‘sustainability’ through a system-wide lens, considering the triple-bottom line inclusive of social, ecological and financial effects. He believes to operationalize ‘sustainability’ it must be reduced to measurable properties. Developing empirical tools to assess current levels, magnitude changes and confidence levels are all integral points in sustainability’s definition. Once these methodologies are in place, it is important to tell the data’s story accurately and without bias mobilizing policy makers driving real change.

With recent developments of the pan-Canadian climate framework addressing the country’s 2030 emissions reduction targets, Posen’s research plays an essential tool for government. Most recently, in conjunction with Professor Heather MacLean and a charitable environmental organization called Pollution Probe, Professor Posen is working on a white paper providing analysis to the Government of Ontario. The paper will provide guidance in provincial emissions from indirect land use change and carbon accounting for biofuels as part of both Ontario Renewable Fuel Standard and Canada’s Clean Fuel Standard.

“It is necessary to remember that though governments can shift and mandate new targets, magnitudes of change in one area will have consequences in another,” Posen says. These market-rebound and indirect effects are an important consideration in Professor Posen’s research.

“It is not as simple as implementing biofuels to reduce green house gases (GHG),” says Posen. According to the professor when addressing GHG mitigation strategies, policy makers need to consider the totality of costs and benefits associated with the proposed protocols. If a food production crop is replaced with a bio-fuel-bound crop, this change will have implications not only in the energy sector but also for world hunger and food scarcity problems. Once bio-fuel crops are harvested, refining the biomass consumes energy, processing will affect air quality and the infrastructure needed to support distribution efforts requires investment. These are only a sampling of considerations to address when evaluating and selecting among the competing uses for biomass and prioritizing GHG mitigation strategies.

Other examples of sustainability analysis issues include prioritizing certain sectors before others, market price fluctuations and accounting for technologies that currently do not exist. New developments create alternative scenarios. Policy makers forge new directions with each new regulation. Some directions will lead to fruitful and tangible results while others will lead to dead ends. Confounding the issue, attributing the origins of outcomes is difficult to disentangle empirically. Posen is working to identify new, precise measurement modelling to improve path forecasting.

Professor Posen’s previous work focused on large-scale systems at global and national levels. He is currently looking to address city-scale systems. As global leaders discuss and stipulate new green targets and frameworks, cities have an important role in implementing and driving their success.

“Often cities do not have an accurate picture of their current emission levels, for example. It proves difficult to identify necessary fundamental policy changes without data to inform the direction,” says Posen. “With increased capacity to collect, analyze and disseminate crucial data points, local officials can make substantial changes that benefit both the short and long run sustainability of cities.”

Professor Tamer El-Diraby
RESEARCH FOCUS: Construction management for societal and corporate changes

Professor El-Diraby agrees the conversation around ‘sustainability’ needs to be more than a passing fad. He notes, buzzword or not, ‘sustainability’ promotes positive results. “It is just a given nowadays,” he remarks. “Most governments, businesses and our society as a whole accept and are prioritizing its implications.”

El-Diraby notes his school-age children studying sciences are now learning through a lens of ‘sustainability’. The generational expectation for sustainable efforts is non-negotiable. Despite its hashtag status, he believes there is a general movement from generic thoughts to actionable policies and programs for energy conservation and climate change. “While we may be bored with its use, caring about these issues is the result of profound belief in ‘sustainability’,” says El-Diraby. The Professor warns that not all who use the term have noble intentions. Some companies are abusing the term and diluting its operational power.

In construction management, Professor El-Diraby focuses on more than just green technology and number crunching. He is interested in the business case, change management and the sociology of embracing ‘sustainability’. The professor is using social network analysis to help discover how communities – both citizens and professionals – view ‘sustainability’. Through crowdsourcing, the Professor is sifting through the noise uncovering interesting insights.

A large portion of his research examines how to manage and support implementation efforts for ‘sustainability’. Leveraging data analytics to help managers discover new knowledge or patterns of change, El-Diraby develops tools to help coordinate decision-making.

Across the global construction industry, many of the environmental and economic challenges with infrastructure systems are the same. However, the social aspects of ‘sustainability’ vary with the developmental phase of the city and country.

In Canada, with pre-existing infrastructure, governing bodies are seeking to change long-standing unsustainable construction practices. In a country like China, which is building new infrastructure, there is an opportunity to incorporate green construction and promote sustainable habits from the beginning. China is seeking to develop while Canada is seeking to optimize its developed systems. The methods are distinct but overall the goals remain the same.

Potential game changers are close, Professor El-Diraby believes for the construction management industry. He is confident the future is poised for many new impacts, which will improve the health and livability of our cities.

Automation | 3D printing and robotics are increasingly used. These technologies provide significant productivity improvements and elevate our capacity to examine complex problems.

Digitization | New technology called Building Information Modeling (BIM) is allowing sophisticated analysis and enhanced cross-border collaboration. The supply chain for construction design, finance and production is globalizing and yielding great benefits.

Net-generation | New construction customers are perceptive. They are acutely aware of sustainable energy options. These new players will force the industry to surpass green regulations and adapt to serve consumer demands.

Modern cities | There is a need for installing and re-configuring our infrastructure to accommodate new urban technologies such as driverless cars.

Professor Evan Bentz
RESEARCH FOCUS: Concrete and structures standing the test of time

“Sustainability is indeed a word that has become less powerful due to repeated use, but still represents an important concept,” says Professor Bentz. Speaking as a concrete expert, the term evokes similar feelings to “resilience” – which the Professor notes is also pervasive in the industry.  In both cases, Bentz believes these terms are important considerations and afford design engineers a point of reference when talking with building owners.

Bentz laughs when he recalls the reception the term artificial intelligence received during the 1980’s. Back then, engineers believed AI was probably impossible and discredited the term quickly. Fast forward to 2017 and AI is now a worthy pursuit many corporate giants are chasing. His bit of trivia elucidates; trending or not, engineers must address ‘sustainability’ today and ready themselves for the unexpected of tomorrow.

When studying concrete, Bentz uses ‘sustainability’ to imply longevity and practicality. “As engineers we need to build lasting structures and, given the constraints of the project, use materials as efficiently as possible,” says the Professor.  “In a sense, it is an attempt to provide an accounting of environmental issues previously neglected by our profession.” Improving building codes and creating increasingly efficient structures are just some of the ‘sustainability’ concepts involved in Bentz’s research.

Viewing ‘sustainability’ from a global perspective, there are only so many construction materials available on this planet. However, despite limited material types, their applications can be vastly different. The surrounding landscape of a building in Toronto is vastly different from a structure in Abu Dhabi. “This is why ‘sustainability’ issues are not taught as a single set of rules like design code regulations,” says Bentz.  “Instead they represent more of a way of thinking and that is partly why we teach ‘sustainability’ in all four years of our program.”

What important changes does the Professor foresee in the future?

Firstly, the availability of timber for large structural projects. “The stuff grows on trees,” he quips.  Another is the potential for large carbon taxes – much larger than current proposals, which could change our concrete mixes. Rather than designing with a small amount of high performance (and high strength) concrete, we might move back towards the older methods of having larger structural elements with a lower carbon footprint per cubic metre.

The most precipitous change for the professor will relate to cement production. Today, cement requires the burning of coal, which is a long-term problem. A cheap and greener method to create concrete would be a game changer for the Professor and industry at large.

Professor Marianne Hatzopoulou
RESEARCH FOCUS: Air quality, transportation and green house gases in cities

Disconcerting but repairable – describes Professor Marianne Hatzopoulou’s position on the word ‘sustainability’. She believes the term is too widely used and more often than not conveys naught. “I don’t think we should stop using it, I actually think we should straighten how it is used,” remarks the Professor.

Like Professor Posen, Hatzopoulou thinks of ‘sustainability’ as the triple bottom line. She does not appreciate the expansions and reimagining efforts people make corrupting triple bottom line’s simplicity. To the Professor, it is a straightforward concept: “We must evaluate the consequences of our decisions on the natural environment, on people and on the economy. Because without a growing economy, I don’t believe that we can be creative or sustainable,” says Hatzopoulou.

‘Sustainability’ drives her research where she specifically looks at air pollution, green house gases and transportation. She admits that her work cannot improve an entire system but, when combined with other research, there can be great change. “I don’t think any researcher can claim that their work on its own will improve the ‘sustainability’ of our cities and society but coalescing knowledge is what really matters.”

In an increasingly complex world, Hatzopoulou’s work on air pollution involves understanding the problem before outlining solutions. Transportation sources create the most air pollution in cities but there is more to the equation. Because air moves, travels, mixes and disperses, assigning responsibility is difficult. The Professor notes the motivation, not just the source of pollutants, is complicated. Those who drive may choose to do so because they do not have access to more “sustainable” forms of transportation. Policy-makers can only affect change within the constraints of their budgets. The automotive industry first and foremost must respond to customer demands. There are many factors to consider and her work looks to account for all.

Though Hatzopoulou may be dismayed by the use of ‘sustainability’ overall she believes Canadians are particularly well versed on green options. “The problem is not a lack of education, the problem exists at a governmental level where long-term and strategic planning is needed to address our uncertain sustainability in the future,” she says.

Road transport emissions and urban air quality have obvious implications to the overall health of our planet. The Professor believes one major change in the future will be autonomous vehicles and all other forms of automated transportation systems. Their ramifications on energy consumption, greenhouse gas emissions and air pollution will shape our cities and the lifestyles for all our residents.

Professor Lesley Warren
RESEARCH FOCUS: Cleaning dirty water from mineral extraction activity

Sustainability through a southern Ontario lens – is what Professor Lesley Warren calls it. In her research, when discussing the importance of ‘sustainability’, most people view the issue with an urban bias.  This is not a problem exclusive to Ontario – throughout the world, residents of urban areas often have a louder voice as over 60% of the world’s population lives in cities.

When thinking of ‘sustainability’ Prof. Warren explains people often overlook the integral role rural and underdeveloped areas of the country play in the ‘sustainability’ of our cities. “From the screens you read your emails on, to the fuel used to power commuter traffic, land far from urban centres has a direct impact on city green efforts,” Warren says.

The Professor is cautious when discussing ‘sustainability’ noting it is an ambiguous and at times pejorative term, which many exploit to oversell products, ideas or initiatives. “It is important to understand the deliverables for green efforts. Without full agreement on desired results, the word is more about marketing than driving tangible solutions,” states Warren.

An effective ‘sustainability’ definition begins with experts uniting and coalescing knowledge from across disciplines and contexts. She reiterates the complex nature of the term, noting that the many stakeholders and perspectives influence the term’s meaning.

City policies have great impacts on rural communities with close ties to the mineral extraction industry; mining wastewaters produced hundreds of kilometers away from urban environments have lasting impacts on cities’ health. Considering the interdependence, our population must come together and consolidate its efforts.

Warren recalls a poignant comment said to her years ago. After mining activity had contaminated the only water supply in a farmer’s African town, he remarked, “You can’t drink money.”  This statement has stuck with the Professor driving her efforts to measure ‘sustainability’ in more than dollar and cents. She regards stewardship, life quality and economic impacts as critical considerations to elicit the best results for the planet.

Collaborating with many mining industry leaders in her research, Warren points to the environmental champions. These advocates not only are reacting to problems, they are adopting proactive tactics. They are minimizing impacts and mining’s environmental legacy for future generations. Mineral extraction is important for the medical equipment discovering new treatments, for the microprocessor in our phones connecting loved ones across the world and for fertilizers responsible for our global food supply. And as we continue to meet our resource demands we can do so mitigating our environmental impacts.

An issue Professor Warren looks to address in the importance of sustainability is in water. It is a precious and finite resource and something the mining industry needs in vast quantities. In areas prone to water scarcity there are competing needs to address. Once minerals are extracted, the wastewater produced must be dealt with safely and securely. Upstream R&D is a focus for Warren. Engaging with industry partners, the Professor and the Lassonde Institute of Mining (LIM) and the new Lassonde Mining Hub (LMH) are pioneering new technologies that will dramatically transform the industry and create proactive solutions.


It is clear that the S-word has been reduced to a hashtag moniker for a trending movement. However, the nobility of effort is something to be celebrated. Mobilizing effects are palatable if the repetition does not alienate people first. Regardless of the trend, the word must amount to more than limited improvements and prioritize significant impacts. Clearly, to do so, definition is important.

The way public discourse uses the word ‘sustainable’ is undoubtedly unsustainable. Green. Eco. Globally-conscious responsibility. The list can go on. Whatever the word choice, the motivation is there and is important to all engineers.

Evolving eco-conscious terminology aside, our professors move past the hype and define ‘sustainability’ for impact and solutions. Here is a recap:

  • Professor Posen wants more numbers.
  • Professor El-Diraby wants to move past generic ideas to thoughtful examination.
  • Professor Bentz wants to ignore the over-use and see the term for that which it inspires.
  • Professor Hatzopoulou wants the term straightened-out.
  • Professor Warren wants a dual-lens from both urban and rural perspectives.