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Ensuring that engineering graduates address sustainability in their work requires more than just teaching them to assess the impact of their activities on the environment and how to install pollution control devices. Engineering graduates will need to understand the factors inhibiting the implementation of clean green technologies and their own roles and responsibilities as engineers in shaping technologies. This paper considers the role of engineers in business and industry and as advisors to government; the insights offered by scholars of science and technology studies; and the need for engineering education to incorporate these insights to enable engineers to better understand the social dimensions of technological change.
The environmentally conscious engineering graduate of the future will not be a mere technician able to competently carry out the technological tasks set by an employer. S/he will be a fully professional, independent adviser who will be able to choose which technologies are most benign and appropriate in terms of sustainability; be able to put a convincing case for such technologies; understand the impediments to their being implemented. S/he will know when it is appropriate to call on environmental consultants, will not hesitate to tell an employer if s/he doesn't agree with a proposal and will be able to advise governments how to encourage desirable technological innovation and change.
This graduate will be no unthinking technological optimist either. S/he will be able to distinguish when a technological solution is appropriate and when a social or political or economic solution is preferable. S/he will understand the social/political context of engineering work, the way technologies are shaped by a variety of social, economic, technical factors, and the potential role that engineers can make towards achieving a sustainable future.
Such a graduate will not automatically emerge from current engineering courses which pay too little attention to professional development and the social context of engineering. A radical reshaping of engineering education is necessary to green prospective engineering graduates.
If engineers of the future are going to contribute towards the sustainability of the planet's ecosystems, they will need to understand:
The need for the first two points should be self-evident so in this article I am going to concentrate on explaining why it is so essential that engineering education address the last two points.
Yet although the burden of technological change seems to lie with business and industry, many firms are not implementing environmentally beneficial technologies, despite their availability. Moreover, efforts to clean up the environment have tended to concentrate on technologies that are added to existing production processes to control and reduce pollution (end-of-pipe technologies and control devices) rather than changes to the production processes themselves.
The alternative to end-of-pipe technologies is to adopt new `clean' technologies that alter production processes, inputs to the process and products themselves so that they are more environmentally benign. It is suggested by Cramer and Zegveld that process technologies should be used that require less water (for example, by alternative drying techniques), energy and raw materials, and that reduce waste discharges (for example by developing detection and separation machinery and process-integrated flue-gas cleaning and filter systems). Also, raw material inputs and processes can be changed so that, for instance, solvent-free inks and paints, and heavy metal-free pigments are used. The end products can be redesigned to reduce environmental damage during both manufacture and use, and waste flows can be reused within the production process rather than dumped .
Clean technologies are preferable to end-of-pipe technologies because they avoid the need to extract and concentrate toxic material from the waste stream and deal with it. The OECD found that, in 1987, most investment in pollution control was being used for end-of-pipe technologies, with only 20 per cent being used for cleaner production. Cleaner technologies are not always available and, even when they are, companies tend not to replace their old technologies until they have run their useful life. Also, companies prefer to keep to a minimum the organisational changes that need to be made; they like to play it safe when it comes to investment in pollution management. An Australian Working Group on Manufacturing commented that, "it is apparent that in many cases end-of-pipe technologies are readily available, easier to adopt and more evident as anti-pollution measures than clean production processes".
Engineers play a key role in advising firms about which technologies are available, which are preferable and which are most cost effective. In order to do this effectively in a way that addresses the sustainability issue engineers need to keep up to date with technological developments in this field and their education should equip them to be able to research this sort of information. More importantly they need to understand and communicate clearly and persuasively the importance of investment in clean technology rather than end-of-pipe solutions both for the future of the planet and the long-term financial success of the firm. A number of studies have shown that clean industries tend to be more profitable . This makes sense because it is wasteful to have additional materials being processed through the production line only to end up as wastes that need to be treated.
Governments tend not to be very good at translating government financed inventions into commercial successes. Policies to subsidise firms to change their innovation processes for environmental protection purposes have not been very successful, either. Experience in the Netherlands between 1975 and 1990 showed that subsidies were not usually spent on clean technologies, and that they usually went to larger firms that would have made the required investments anyway. Moreover, subsidies have tended to lead to development of end-of-pipe technologies rather than changing the direction of the technologies being developed .
Governments can also encourage the development and implementation of clean technologies through the use of laws and regulations which cannot be met without technological change, or through the use of economic instruments which are meant to provide a financial incentive for technological change.
A number of studies have shown that environmental legislation can be a key factor in many industry innovations. A study of 164 innovations in Europe and Japan found that regulations (mainly environmental and safety) not only promoted innovation but were a factor in the success of these innovations, particularly in the chemical and automobile industries . This was because the technology for meeting the regulations was often readily available; it had not been implemented because company engineers had other priorities. Government regulations had forced a reordering of priorities, allowing technological changes to take place fairly quickly, and environmental and safety improvements followed.
However, regulation seldom leads to the development of radically different technologies but rather to technologies closely related to those already being used. Laws and regulations tend to lead to end-of-pipe technologies because they are usually too weak and are aimed at quick remedies to severe environmental problems. In order for them to affect the original design and shape of a technology, they need to be very stringent--so stringent that existing technology will not suffice. They also need to be introduced progressively so that a firm can anticipate what will be required and have time to develop innovations.
In some cases in the USA, standards have been set on the basis of environmental or health requirements rather than on available technologies. This has resulted in new technologies being developed and implemented. Lawsuits, regulations and the threatened ban on PCBs forced PCB users to develop product alternatives. Most of these substitutes were cheaper than the PCBs they replaced. Bans on CFCs in aerosols resulted in two innovations: a non-fluorocarbon propellant was developed using carbon dioxide, and a new pumping system was introduced that did not depend on propellants and was actually cheaper .
Wastewater pre-treatment standards proposed for effluent from the electroplating industry were predicted to force a closure of 20 per cent of electroplating workshops. A research and development project following this announcement produced a new rinsing method--the `providence method'--which reduced water consumption by one-third and cut hazardous waste production by 50 to 70 per cent .
All of these cases show that constraints on industries are not necessarily detrimental to their viability. Charles Caldart, of the Centre for Technology and Industrial Development, MIT, and William Ryan of the Massachusetts Public Interest Research Group, have jointly expressed the conviction that regulatory approaches "must not be bound by existing technologies and existing economic conditions. Rather, public policy must encourage the type of innovation that can spur technological breakthroughs and alter economic circumstances. In short, we believe it is possible to change production technologies." .
Economic instruments also seek to encourage technological change by providing a financial incentive to encourage firms to direct their research and development towards environmentally sound technology. However, like legislative instruments, economic instruments have tended to be too weak to achieve any real technological change. The OECD has found that in most cases charges are too low to provide such an incentive and merely act to redistribute money from the polluter to the government . Similarly, tradeable pollution rights have been found to save money for industry but not to have improved environmental quality significantly .
Because of the reluctance of governments to act against business interests, legislation and economic instruments are seldom tough enough to foster technological change of the type required for ecological sustainability. Although such regulation would probably strengthen business in the long run, business people see strong government intervention as an infringement on their autonomy. Prominent US environmentalist Barry Commoner argues that business people are supported in this because there remains a strong public conviction "that the decisions that determine what is produced and by what technological means ought to remain in private, corporate hands."
Currently engineers advise government about what technologies are currently available at reasonable prices for firms to meet environmental standards, that is the best practicable technology (BPT). Engineers could more usefully lobby governments to apply regulations that encourage technological innovation. To do this, they need not only to know what technologies are currently available but to understand the processes of technological development so that they can advise regulators what might be achieved with a few years of sustained research and development. This means engineering education needs to incorporate more than just a superficial history of technology that outlines dates and inventors and inventions. It would need to include material from the field of science and technology studies that considers technological systems, paradigms and trajectories and how different social groups influence technological change.
Historical accounts of technological change have traditionally depicted a linear process of development with inventions leading to innovations, innovations leading to the diffusion of technological products and each technological change leading on from the last in an orderly and inevitable progression. More recently, however, the science/technology relationship has been reappraised and there is far more study directed at finding out more about the nature of invention, development and innovation .
The simplistic view that economic or market forces fully explain technological innovation has been recognised as inadequate as has the view that technology is an autonomous force that determines social change. Modern science and technology studies view the social, economic, political, technological and scientific realms as interacting. The interactive model has been expressed in various ways. One way has been to view technologies as forming systems which embody social, economic, political, technological and scientific dimensions. The various interpretations and perspectives of a technology can also be drawn out by considering the network of social groups who have an interest in it. Another way is to focus on technological decision makers and the various social, economic and political factors they consider in reaching their decisions, or to focus on engineers to show how they draw all these elements together in technological innovation, design and practice.
Thomas Hughes' study of electricity generating systems was a key work in the system view of technological development . Hughes' technological system included physical artifacts, organisations, scientific components (including publications, research programs and university courses), laws and natural resources. The view of technology as multi-faceted has been taken up by others. For example, Wiebe Bijker has defined a "technological frame" which would include current theories, tacit knowledge, engineering practice, specialised testing procedures, goals and practice and would involve various social groups to various degrees .
A notable contribution made by Hughes and his systems approach was incorporated in his concept of "technological momentum". As a technological system grows, he argued, it develops a mass which is made up of institutions and people who have a vested interest in maintaining the system. These include manufacturers who have invested in resources, labour and manufacturing plant for the system, educational institutions that teach the associated science and practice, research institutions, professional societies, as well as people such as engineers and managers who have invested their experience and expertise in the system. The system not only has mass but also direction; that is, development of the system proceeds along conservative lines that can be extrapolated. Changes in direction are resisted and radical inventions are unpopular because they deskill people, wipe out financial investments and stimulate anxiety in large organisations. When faced with a problem that threatens the stability of the system, the engineer, rather than considering building a new system, tries to rearrange or manipulate the system components or perhaps to incorporate a hostile environment .
Other authors have focussed on the original choice between competing technologies which may be at the basis of a technological system. The use of actor networks has been used to elaborate on the role and perceptions of various social groups in this choice. The key point that these analyses make is that the choice of a technology is not merely based on narrow economic and technical considerations, but involves social choice. Trevor Pinch and Wiebe Bijker adopted this approach. They argued that various social groups can attribute very different meanings and problems to an technological product or artifact and for each problem associated with the artifact there would be various possible solutions, each with moral, judicial and technological aspects .
Others have elaborated on how these different social groups have varying degrees of power over the shaping of a technological artifact. Peter Weingart has observed that technological systems, even those producing consumer goods for the market, can be implemented without regard for public acceptance. "The alliance of government bureaucracies, engineers and private corporations - the latter acting as quasi-public agencies by being subsidized directly or indirectly - circumvents the market and operates through the medium of political power. Consequently, non-acceptance of such technologies by the public can only find expression in political resistance, leading to legitimation problems with grave political rather than mere market failures." 
As Stewart Russell has pointed out, many alternative technologies are never presented to the consumer or outside social groups because of an internal selection process in the invention and innovation process. Those that are presented are already socially shaped and formed "the product of researchers' or designers' interpretation of need".
Scholars in the field of science and technology studies have looked to the parallel but more developed field of history and sociology of science for approaches to their work. For example, Kuhn's work on the nature of scientific revolutions and the every day, "normal" work of scientists has been found to yield analogies in the area of technological change and engineering practice. The work of engineers exhibits some of the qualities of "normal" science in that research is generally of a gradual cumulative nature, making improvements on past achievements and that solutions are sought from within a restricted range of possible solutions. Similarly practice is based on applying the appropriate technological methods from an arsenal of "tried and true" methods.
Edward Constant argued that the routine work of engineers and technologists, which he called 'normal' technology, involves the "extension, articulation or incremental development" of existing technologies. A technological tradition, Constant said, is subscribed to by engineers and technicians who share common educational and work experience backgrounds. The tradition relates to a field of practical endeavour rather than to any academic discipline .
Giovanni Dosi described a technological paradigm as "an "outlook", a set of procedures, a definition of the "relevant" problems and of the specific knowledge related to their solution." Such a paradigm, Dosi said, embodies strong prescriptions on which technological directions to follow and ensures that engineers and the organisations for which they work are "blind" to certain technological possibilities. Dosi identified a technological paradigm in four dimensions. The first related to the generic tasks to which it is applied and the second to the material technology it selects. The third related to the physical/chemical properties it exploits and the fourth dimension was the technological and economic dimensions and tradeoffs which are associated with it. These tradeoffs, he said, provided the direction for improvement of the technology .
Richard Nelson and Sidney Winter also observed that there is sometimes a technological "regime" or paradigm operating which relates to the engineer's beliefs about what is feasible or at least worth attempting. They explain why technological change within a paradigm seems to follow certain directions: "The sense of potential, of constraints, and of not yet exploited opportunities, implicit in a regime focuses the attention of engineers on certain directions in which progress is possible, and provides strong guidance as to the tactics likely to be fruitful for probing in that direction. In other words, a regime not only defines boundaries, but also trajectories to those boundaries." 
David Wojick concentrated more on engineering practice in his description of technological paradigms and he said that 'normal' technology involved the "artful application of well-understood and well-recognised decision-making procedures". In this way there is no ambiguity or doubt about what counts as a good solution within the engineering community .
Science and technology studies scholars have shed important insights into the social dimensions of technological development and these are important to understanding the impediments to clean and environmentally sound technologies and how governments and the engineers that advise them can shape and direct future technological development in ways that will be socially and environmentally beneficial.
Attempts to invent and design different types of technology that are more environmentally sound are not new but they have largely failed because of a lack of understanding of the constraints on changing technological trajectories. The `appropriate technology' movement which blossomed in the 1970s encompassed many such unsuccessful attempts. The appropriate technology movement has been going for more than twenty years in many countries, and today involves an extensive network of groups, an identifiable literature of its own, as well as numerous demonstrated technological innovations. Despite this, it has failed to influence the pattern of technology choice exercised by mainstream society. Kelvin Willoughby, a scholar who has studied this movement, points out that while it has "achieved a modestly impressive track record of successful projects" and despite the "appeal and commonsense nature of the movement's core ideas, the movement has largely failed to evoke the transformation of industrial and technological practice in most countries in accordance with the principles of Appropriate Technology. In other words, while becoming a significant international movement Appropriate Technology has remained a minority theme within technology policy and practice." 
Langdon Winner has argued that most people in the appropriate technology movement ignored the question of how they would get those who were committed to traditional technologies to accept the new appropriate technologies. They believed that if their technologies were seen to be better, not only in terms of their environmental benefits but also in terms of sound engineering, thrift and profitability, they would be accepted .
The mistake that many advocates of appropriate technologies made was to fail to understand how modern technologies had been developed and why they had been accepted or why alternatives had been discarded. Winner claims that "by and large most of those active in the field were willing to proceed as if history and existing institutional technical realities simply did not matter" . If engineers of tomorrow are to avoid this mistake they need to be knowledgeable about the historical development and social context of technological change.
Finally it is important for engineers to counter naive technological optimism--the faith that technology by itself can achieve miracles. Engineers should be able to give honest and reliable advice about the limits of technological solutions and to assess whether, if cleaner technology can be implemented, the reductions in pollution will be enough. Dutch Professors Cramer and Zegveld argue that technology cannot be expected to solve major environmental problems if production continues to grow at its current rate. Giving the example of their own country, where the purchasing power of the average person is expected to increase by 70 per cent by the year 2010, they argue that "an incredible reduction in discharge levels and waste flows per product unit would have to be realised to achieve the aim of a sustainable society". They believe this is not realistic. On top of this, production would need to increase ten times if everyone in the world were to live at the same standard of living currently enjoyed by those who live in affluent countries. They claim that the growth of both production and freely disposable income would have to be restricted if pollution levels are to be reduced .
It seems that technological change alone may not be enough. Unless substantial social change occurs, the present generation may not be able to pass on an equivalent stock of environmental goods to the next generation. Increases in population and consumption seem sure to swamp the sorts of improvements that have been achieved by technological innovation to date. Whether a more radical reshaping of technological systems can counteract the rising tide of resource use and waste production remains controversial. But even the achievement of such radical technological change will require social and political change.
Never before has it been so vital for engineers to understand the social dimensions of their work. Engineers will continue to be most concerned with and have most influence in the area of technological change but the type of radical technological changes required will require more than good designs and suitable inventions.
Ensuring that engineering graduates address sustainability in their work requires more than just teaching them to assess the impact of their activities on the environment and how to install pollution control devices. Engineering graduates will need to come to terms with the causes of environmental degradation as well as the social and political factors which shape and direct technological change. They will need an education that gives them this understanding as well as the courage and professional integrity to independently pursue sustainability.
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