Download PDF Fall Bridge on the Value Proposition in Innovative Engineering September 22, 2023 Volume 53 Issue 3 This issue explores the unique value proposition that engineers and engineering disciplines present in addressing the National Academies’ Grand Challenges. Covering topics ranging from the global sustainability challenge to the sequestration of carbon to transformations in our water management system, the articles in this issue show how engineers are vital to creating a world in which humanity can thrive. The Value of Engineering for Sustainability Thursday, September 28, 2023 Author: Michael D. Lepech and James O. Leckie Engineering disciplines present a unique value proposition in addressing the global sustainability challenge. Sustainability is one of the major existential challenges of our time. Across four broad realms of human concern (sustainability, health, vulnerability, and joy of living), the National Academy of Engineering (NAE) prioritizes sustainability-related challenges as “foremost” since they “are those that must be met to ensure the future itself” (NAE 2008). The NAE justifies that prioritization by recognizing that “sustainability is based on a simple and long-recognized factual premise: Everything that humans require for their survival and well-being depends, directly or indirectly, on the natural environment” (NRC 2011). It is clear that our global society must collectively and urgently address our needs for low-cost generation of environmentally friendly power (e.g., solar, wind, geothermal, fusion), development of effective and scalable carbon sequestration methods, stewardship of the global nitrogen cycle, and provision of ubiquitous access to clean water (NAE 2008). Unsurprisingly, such sustainability-focused challenges are multi-dimensional and very complex, spanning various disciplines of knowledge, spatial regimes, and temporal scales. They reside in Donald Schön’s classification of challenges that exist within the “swampy lowlands, where situations are confusing messes incapable of technical solution and usually involve problems of greatest human concern” (1984). If purely technical solutions are not sufficient, what is the value of engineering, a discipline that rigorously applies mathematics and science to solve real-world problems, in addressing our existential sustainability challenge? What unique value proposition do engineers offer, in concert with other fields including policy, the humanities, medicine, business, etc., in expeditiously solving our global sustainability challenge? If purely technical solutions are not sufficient,what is the value of engineering, a disciplinethat rigorously applies mathematics and science to solve real-world problems, in addressing our existential sustainability challenge? It may appear easy to claim that engineers provide unique value when addressing large global challenges like sustainability. Over the last 150 years, engineers have been responsible for some of humanity’s greatest achievements and solving some of our greatest challenges. These accomplishments include electrification, automobiles, airplanes, modern water supply and distribution, radio and television, computers, telephones, spacecraft, air conditioning, and the Internet, among many others (Constable et al. 2003). There is little doubt that engineers have great potential to meet our societal needs and overcome large challenges. But is this the case for the truly global and uniquely immediate challenge of sustainability? Given the “swampy” nature of this global sustainability challenge, it can be helpful to structure the ways in which engineers can contribute using an impact framework originally introduced by Paul Ehrlich and John Holdren (1971). They recognized that the impact (I) on the environment from human development is a function of both the human population (P) and per capita environmental impact (F), which itself is a function of per capita consumption (A) and the environmental impact associated with each unit of consumption (T). Taken together, this forms the master equation in the field of industrial ecology (equation 1), relating population, affluence and consumption, technology, and impact (Chertow 2000). I=PAT (equation 1) This IPAT equation provides a clear framework by which we can begin to evaluate the unique value of engineers in potentially solving our global sustainability challenge. Engineering for Sustainability through Technology Innovation The US Department of Labor succinctly describes engineering as the application of “the theories and principles of science and mathematics to research and develop economical solutions to technical problems.” Through the invention and creation of new technological solutions to meet societal needs, many engineers are working to address our global sustainability challenge by reducing the impact associated with each unit of consumption (the “T” in IPAT). For example, advancements in mechanical engineering have significantly increased the fuel efficiency of automobiles in the United States over the past fifty years. As shown in figures 1a and 1b, the average fuel economy and real-world carbon dioxide emissions of today’s light-duty vehicles produced in the United States have improved by 32% and 25%, respectively, since model year 2004 (EPA 2022). Improvements in efficiency and emissions since 1975 have been even more substantial. Model year 2021 light-duty vehicles produced in the United States offered consumers the highest fuel economy (25.4 miles per gallon) and lowest environmental impact (grams of CO2 emitted per mile) in the history of the US automobile industry. These trends are expected to continue as increased numbers of electric vehicles that can be charged from renewable energy sources are introduced into the marketplace. The contribution of numerous fields of engineering (designing highly efficient internal combustion engines, building roadway infrastructure that enables automobile transit, creating new electric vehicle batteries with low-carbon charging technologies) in reducing the “T” in IPAT is different from other professions in that engineers apply principles of science and mathematics, within the context of economics and policy, to offer technical solutions. The potential contribution of engineers to the technological portion of our sustainability challenge is not unique to automobiles or transportation. Nearly twenty years ago, Stephen Pacala and Robert Socolow identified fifteen scalable strategies to reduce annual global carbon emissions by 1GtC by 2054 (Pacala and Socolow 2004). Of these fifteen potential strategies, twelve were technology focused, recognizing the need for engineers working at industrial scales to solve this problem. These technology-focused strategies include fuel-efficient vehicles, energy-efficient buildings, efficient coal-fired baseload powerplants, efficient gas-fired baseload powerplants, carbon capture at baseload powerplants, carbon capture at hydrogen production facilities, carbon capture at synfuels plants, increased nuclear energy production, wind energy production, solar energy production, and biomass fuel production. Ever since these strategies were proposed, additional technology-focused strategies have arisen, including baseload clean energy production from geothermal heat, utility scale energy storage, and most recently clean energy production from fusion (e.g., Atzeni et al. 2022; Chen et al. 2018; Moncarz and Kolbe 2017). These are in addition to the broader sustainability needs outlined by the National Academies, including development of effective and scalable carbon sequestration methods, stewardship of the global nitrogen cycle, and provision of ubiquitous access to clean water, as mentioned earlier (NAE 2008). Developing technologies to pursue all of these strategies at a rapid, global scale is a unique contribution of the engineering profession. Engineering for Sustainability by Addressing Consumption It has long been recognized that technology-focused solutions alone will not solve our global sustainability challenge (Chertow 2000). Changes in the ways we consume goods and services and the amount we consume must also take place (the “A” in IPAT). In recognition of this reality, Pacala and Socolow (2004) also identified consumption changes such as “reduced use of vehicles” as an important strategy, on par with increased fuel efficiency of vehicles, to reduce the global carbon emissions rate. Building upon our previous example of light-duty vehicles, while engineers have been effective in reducing the impact of light-duty vehicles per mile traveled (a 25% carbon emission reduction per mile since model year 2004), our nation chooses to drive increasingly more. As shown in figure 2, annual vehicle miles traveled in the United States has increased steadily since 1971 (FHWA 2023). The only exceptions to this trend are the economic downturns visible in 1974-75 and 1980-82, the Great Recession and the recovery from it (2007-2014), and (most visibly) the COVID-19 pandemic in 2021. When considered together with a nearly 200% growth in driving consumption since 1970, the technological improvements in vehicle efficiency and emissions per mile shown in figures 1a and 1b are less impressive. The engineers who reduced vehicle emissions per mile traveled in figures 1a and 1b also made auto-mobile transportation more affordable by increasing fuel economy, thus making driving cheaper and unfortunately leading to increased consumption and overall environmental impact. However, this decades-long relationship between increased fuel efficiency and increased consumption may finally have been broken by technology. As also seen in figures 1a and 1b, US vehicle miles traveled have yet to return to pre--pandemic levels, even though GDP growth has recovered since the pandemic ended. During the pandemic, our need for interpersonal or business connectivity was met through advancements in new communication technologies such as Zoom, Teams, Skype, and others. This is only one example of how engineers create opportunities to meet societal needs via complete shifts in technology, while at the same time eliminating impactful forms of consumption (e.g., driving many miles for business meetings) and thus contributing to scalable sustainability solutions. Engineering for Sustainability via Systems Thinking While the simplicity of IPAT may provide a convenient structure for potentially dissecting the value proposition of engineers in addressing the global sustainability challenge, it fails to capture one of the most important skillsets of engineering: systems thinking. As asked previously, if purely technical solutions are not sufficient, what is the value of engineering, a discipline that rigorously applies mathematics and science to solve technical problems, in addressing our existential sustainability challenge? Phrased differently, what unique value proposition do engineers offer, together with other fields including policy, the humanities, medicine, business, etc., in solving our global sustainability challenge? A foundation of engineering education, and thus engineering practice, in the United States is the application of systems thinking approaches to complex problems that include all three components of sustainability (economic, environmental, and social). Standard student outcomes for engineering programs accredited by the Accreditation Board for Engineering and Technology (ABET) in the United States reflect this foundational systems-thinking concept by explicitly requiring: (i) an ability to identify, formulate, and solve complex engineering problems by applying principles of engineering, science, and mathematics, (ii) an ability to apply engineering design to produce solutions that meet specified needs with consideration of public health, safety, and welfare, as well as global, cultural, social, environmental, and economic factors, and (iii) an ability to recognize ethical and professional responsibilities in engineering situations and make informed judgments, which must consider the impact of engineering solutions in global, economic, environmental, and societal contexts (ABET 2021). Engineers are uniquely educated, from the outset, to explicitly consider complexity and impact in global, economic, environmental, and societal contexts during their work, aligning well with the types of solutions that will be needed to address global sustainability challenges. In practice, we see engineers engaging in systems-thinking and providing solutions to the complex sustainability challenge by co-creating what researchers at Stanford have termed “metastructure,” a transcendent form of infrastructure that provides a platform upon which global sustainability challenges can be more effectively addressed at scale. Metastructure includes physical infrastructures, digital IT technologies, regulations and policies, financing mechanisms, community engagements, businesses and business models, partnerships, and other institutions. This set of technologies, policies, and organizations must be created, applied, and sustained in concert with each other to provide economic, environmental, and social sustainability, in addition to a high quality of life for people around the world. First proposed as a concept for the development of new urban transportation systems (Rogers 2016), Anne Kiremidjian and Michael Lepech (2023) describe metastructure as an integrated hierarchy of infrastructures that enable diverse disciplines to effectively collaborate on complex challenges like sustainability. Such integration increases the likelihood of successfully addressing these challenges in a more effective, scalable, and timely manner. As discussed by Kiremidjian and Lepech, metastructure is comprised of three types of infrastructure: (i) physical infrastructures that incorporate a dense sensing and data collection network (e.g., public spaces with CCTV cameras, roadways equipped with traffic sensors, smartphones providing real-time feedback), (ii) computational infrastructure that translates the ever-growing stream of data into information that can be used by individuals, businesses, and governmental agencies (e.g., machine learning algorithms, reinforcement learning processes, artificial intelligence) and (iii) engagement infrastructure that includes regulations and policies, financing mechanisms, community engagements, businesses and business models, partnerships, and other institutions. Engineers of all disciplines, working together with other fields including policy, the humanities, medicine, and business, are central to the creation of these systems of infrastructure and the deployment of components that link them interoperably. Thus, we see engineers as the core systems integrators that will enable society to overcome complex and urgent sustainability challenges. The Engineering Value Proposition When viewed through the triple lens of relevancy, measurement, and differentiation, engineering disciplines present a unique value proposition in addressing the global sustainability challenge. As described through IPAT, engineers are potentially highly relevant to overcoming this challenge by inventing and creating new technological solutions that meet societal needs in less impactful ways. Further, engineers are relevant to the sustainability challenge by creating new, less impactful goods and services that empower consumers to meet their needs in more sustainable ways. The value proposition of engineers in addressing the sustainability challenge is uniquely measurable. As observed in the IPAT automobile example, the influence of engineers in improving fuel economy and reducing per-mile emissions, both of which contribute to significant reductions in carbon emissions related to automobile travel, can be measured and attributed. While more difficult to quantify, the influence of engineers on the introduction of new electric vehicle platforms, battery technologies, and renewable charging infrastructure is difficult to understate in the coming decades. It is important that engineers (individually and collectively) realize a responsibility to use the tools of their discipline to solve, not exacerbate, global sustainability challenges. Finally, the value proposition of engineers to addressing the global sustainability challenge is differentiated from that of other professions. As discussed previously, engineers apply the theories and principles of science and mathematics to research and develop economical solutions to problems. Engineers bridge the chasm between scientific and mathematical discovery and meeting the consumption needs of our society. Engineers create the tools and infrastructure systems that enable the effective societal engagement of many other professions through regulations and policies, financing mechanisms, community engagements, businesses and business models, partnerships, and other institutions (i.e., metastructure). An Engineer’s Responsibility and Call to Action While there may be real value for engineering disciplines to address the global sustainability challenge, it is important that engineers (individually and collectively) realize a responsibility to use the tools of their discipline to solve, not exacerbate, global sustainability chal-lenges. While the CO2 emission rate of light-duty vehicles produced in the United States has decreased significantly over the past few decades (figure 1b), absolute CO2 emissions from the United States transportation fleet (including medium- and heavy-duty trucks) have increased over the same time period (CBO 2022). Engineers have a responsibility to recognize their potential value in solving global sustainability challenges and to realize this potential through responsible practice and engagement, acting with urgency since time is truly “of the essence.” Beyond individual actions, this responsibility includes a call to work with colleagues around the world to address global sustainability. In many cases, the provision of basic services (e.g., electricity, water, food) overwhelms considerations of environmental sustainability and social equity. Leveraging the technological parts of IPAT, engineers are called to develop and disseminate viable solutions that elevate quality of life while not sacrificing natural environments. Indeed, this may be the most challenging role for engineers to play when working to address the global sustainability challenge in a timely fashion. Conclusion When viewed through the frameworks of IPAT and value proposition, it becomes clear that the discipline of engineering is critical to addressing our global sustainability challenge. When combined with the comprehensive -systems-thinking approach that is required in US engineering education, the value of engineers in rapidly addressing this collective challenge only grows. While the profession of engineering cannot solve the global challenge of sustainability alone, engineers provide a unique value proposition for solving -sustainability-focused challenges that are multi--dimensional and very complex, spanning various disciplines of knowledge, spatial regimes, and temporal scales. Working across pro-fessional silos in aspirational ways, the field of engineering will be key to the goal of delivering more sustainable economies, environments, and societies around the globe for centuries into our future. Acknowledgements The authors would like to acknowledge the valuable contributions of many colleagues who have contributed to this work through thoughtful conversation, rigorous questioning, and collaborative idea generation. References ABET (Accreditation Board for Engineering and Technology). 2021. 2022–2023 Criteria for Accrediting Engineering Programs. Online at https://www.abet.org/wp-content/uploads/2022/01/2022-23- EAC-Criteria.pdf. 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Lepech is professor of civil and environmental engineering, Stanford University, faculty director of the Stanford Center for Sustainable Development and Global Competitiveness, and senior fellow, the Stanford Woods Institute for the Environment. James O. Leckie (NAE) is Emeritus C. L. Peck, Class of 1906 Professor of Environmental Engineering and Geological and Environmental Sciences (by courtesy), Stanford University, and founding faculty director of the Stanford Center for Sustainable Development and Global Competitiveness.