Prof. Abdennaceur Karoui

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Written by A Karoui

Teaching Renewable Energy (RE) science and technology, the current status and prospects for meaningful actions.

An open letter to educators and energy stakeholders on the urgency for teaching RE at all levels.

Dear Colleagues, Education Managers, and Entrepreneurs,

It is time to start paying attention to teaching younger generations one of the most needed knowledge that will help the nation to build and sustain a new energy infrastructure capable of providing the energy we will need in the near future and beyond. This will also save our planet from the pollution cancer that is devouring its body, due to centuries of CO₂ emission from burning hydrocarbons.

Teaching Renewable Energy (RE) like any other STEM discipline has indeed become critical for preparing a sufficient and skilled workforce, knowledgeable engineers, talented inventors, and a well informed business-force capable of rationally promoting true and robust RE technologies. While strengthening STEM education and research programs, strong foundation of RE sciences and technologies will enable a science-based awareness of environmental problems and the invention of durable solutions. Actually, on this responsibility hinges the survival of mankind. Today, about 3 million Americans work in clean energy industry. That number was 2.4 millions, two years ago, and is expected to increase by 50% each five years [1], and yet there is not enough workforce with sufficient skills and correct understanding of RE technologies, let alone the underlying sciences. Equally important is the production of engineers and inventors capable of substantially improving RE technologies. These educational needs are overdue, as many RE mega-projects appeared ill-designed, due to a visible lack of knowledge transfer to project designers, managers, operators, and owners. These ill-designed RE technologies are proliferating, due to the misunderstanding of the fundamental concepts and to current status of the business with a little concern of the future. These might at best delay the broadening of the use of RE, but could also be fatal for the expansion of RE technologies and replacement of the legacy hydrocarbon-based infrastructure.

      I will be discussing in this letter the current status of RE teaching and will justify the need for making it one of our education priorities. I will also present a RE Curriculum and Laboratory Equipment that we have been developing that we hope to be useful and contribute to early preparation of next generation students, engineers, and inventors. Education professionals, independent learners eager to obtain RE vocational education, and RE enthusiasts are invited to participate in a forum that discusses matters related to broadening RE teaching.

Emergence of RE Science and Technology Education

Historically, teaching RE science and technology has sporadically emerged, back in the seventies, after the oil crisis and the publication of some landmark books on photovoltaic materials, devices, and systems. The saga of writing down the beautiful multidisciplinary photovoltaic theories and the then emerging technologies started by R. K. Willardson [2], and the remarkable book by H.J. Hovel [3], as well as books by R. Bube [4], C. Backus [5], A. Laugier [6], K. L. Chopra [7], and the excellent "Willardson and Beer" Series [8]. Thereafter, hundreds of books have been published, notably the excellent books by Jenny Nelson [9], Martin Green [10], S. Fonash [11], and Luis Castañer [12], to name some of the most influential ones. Among these, only few could be partially adopted as undergraduate or graduate textbooks, though mix and match and modifications by the instructors are required to properly support their courses.

       In most electronics textbooks, sections on photodetectors and on solar cells are systematically included here and there, such as in the excellent book of Streetman [13], but rarely entire chapters were dedicated to photovoltaics. As far as solid state physics textbooks are concerned, many treat optoelectronic properties of solar materials, and smart materials such as electrochromic materials used for making smart solar windows, for they are relevant at many levels.

       For the solar thermal energy, one can cite the early books by J. R. Howell [14],[15],[16],[17],[18], which have been used in research and RE system design.

       As far as wind energy is concerned, the engineering aspect has been prominent. Compared to photovoltaics, it has been an older subject; however, the science foundation was not properly and systematically taught back then. In recent decades, Wind Energy Courses have emerged in Mechanical Engineering programs, in such context the undertaking was logical and easier to implement, compared to other RE areas.

       RE teaching started with infusion of chapters in various STEM programs and taught at both undergraduate and graduate programs. That practice is still dominant today and usually done under the teachers’ own initiative. Many avant-garde teachers developed minors and concentrations and some sort of curricula, a collection of electives; these were usually associated to established STEM programs in their departments.

       In high school, teachers mentored students to establish small RE clubs and to develop projects for Science Olympiads. In addition, students taking Advanced Placement (AP) science courses tend to consider solar energy and other RE forms in their research projects.

       The National Renewable Energy Laboratory (NREL) has done an excellent job in developing and presenting production tools, many have been adopted by professors in Engineering schools, Professional Masters, and Technical colleges to teach students and train para-professionals in the various RE fields. Also several divisions in NREL, the National Center for Photovoltaics (NCPV), and others have nurtured the “Hands On Photovoltaic Experience" program [19],  the “Solar University-National Lab Ultra-Effective Program” [20],  internships, and other outreach programs, which played a great role in supporting the nascent RE industry and small business companies flourished as a result of that effort. Many of these programs and developed tools, which are freely offered to RE users, have been used as stepping stones by many institutions to establish new RE education activities in their schools. However, these remain scientifically and pedagogically unstructured and insufficient; they have been narrowly used. Most importantly, these programs do not seem to have produced the sought effects on wider populations of students across the country and high level scientists and researchers, in these pressing times. Large number of, if not most, schools, faculties, and students are unaware of these developments.

       Using EERE/DoE funding, certificate programs for technicians have been established in many states. California and New York were pioneers in a large endeavor as early as 1998, mostly using support from DoE, the States, and private businesses. The certificate programs were generally run by private companies, and have expanded thanks to online offering capped by on site short practical trainings. Instruction materials and textbook have become available, for instance: [21],[22].

       In the past decade, an important development happened for many MBA programs in the US and similar programs around the world. The teaching of energy (traditional) business and management was shifted to the new renewable energy and technology based business. This has invigorated the RE business; a persuasive example is the Duke's Fuqua School of Business, at Duke University [23] and the associated RE clubs run by graduate students. However, it should be noted that these programs do not focus on the science and technology aspects, already complex for specialists, but the business aspects, for which lexical use of the RE terminology seems to suffice. However, in my opinion, that is one of the factors that allowed business to grow regardless of appropriateness of the technology, the future of that technology relative to better ones coming on the line,... which in reality represent a dangerous path that can lead to wasting billions of dollars, if wrong paths are taken. As example, the Re ecosystem embedded in the much larger energy technology-economy system was led to adopt the legacy view of centralization of RE production, which is contrary to the nature of RE sources, being diluted. Hence, the adoption of large PV plants (hundreds of megawatts) instead of rooftop PV is obviously a wrong choice.

       In the US teaching RE has been offered to 42 Master and 55 Bachelor degree programs, mostly using the sustainability aspect, and to less extent the underlying science and more so the technologies of the future. About half of the technical colleges deliver associate degrees with certificates in installation and servicing RE systems. Also several private companies offer accelerated studies for technicians, who obtain certificates useful for jobs with limited skills.

       Another important RE education has been promoted through research training, and performing senior projects. This pathway has been offering the most advanced knowledge in RE and provided potentials for creativity. Undergraduates have been engaged with research groups, many are extremely knowledgeable and have created the technologies for various RE areas, in particular photovoltaics, but also solar thermal, solar desalination, smart windows, conscious architectural design, wind energy, and biomass energy. Research training for undergraduates have become a fashion to promote large research projects, where research training components often motivate the funders. In my opinion, this path needs to be enhanced and generalized, as it is the one that will produce scientists and innovators who will produce new knowledge and will bring the needed new technologies. To that end high school and undergraduate physics, chemistry, and engineering curricula must prepare students to integrate research groups and be even more productive in research, by offering complete courses in RE, or at least including chapters in STEM courses.

Reasons for the Delay of Systematic Teaching of RE Science and Technology

       It is informative to quickly compare the path of RE science and technology teaching with biotechnology and environmental science, which have emerged at about the same time. While teaching of both biotechnology and environmental science have quickly obtained a wide acceptance by schools and students, RE could not attain enough acceptance in academia despite the fact that, RE areas have championed some of the largest research and engineering productions in the world. For instance, an extremely large number of R&D projects have been performed in photovoltaics and tens of thousands of excellent papers have been published in the past decades. As a result, tremendous amount of knowledge has been developed, but has not been relayed to the students through a systematic teaching. Unlike RE, biotechnology courses have been initially included in (or associated to) biology and chemistry programs, and thereafter entire programs have been setup and have drawn a large number of students. This success has been helped by the sharing of the same education infrastructure, the readiness of the industry, and the job prospects for the students.

       One of the main reasons for the delay of a Broader Teaching of RE is the complexity of the relatively recently garnered knowledge, and the unique infrastructure needed for teaching, which did not exit and had to be developed from scratch. Also, the more diverse and changing technologies, unlike biotechnology, have contributed to the delay of the sought systematic teaching of RE. The RE technologies have been, indeed, continuously improving, thereby causing significant changes, and a sort of instability of teaching initiatives and the few established curricula.

       It is clear that, although RE are extremely relevant for our energy and environment future, their introduction in schools has been seriously neglected, except in a relatively small number of universities and high schools. Technical colleges seem to do better than universities in developing RE workforce (apprentices, technicians and students who opt to continue an engineering degree in universities) by providing some technical teaching and practices. However, such teaching is limited to suite industry skill demands, such as design of small RE projects for consumers, system commercialization, installation, maintenance, and upgrading. Some high schools encourage their students to learn RE technologies, usually empirically, and present projects in extra-curricular activities such as science Olympiads. Obviously, in both cases fundamental science, and structured technology and engineering teaching are largely lacking.

Current Status of RE Science and Technology Education

       Some of the least taught science areas and technologies are those underlying RE, alternative energy sources, and energy conservation, despite the strong interest of students in learning RE, and despite our need for sustainable energy sources now and more so in the future. There are many factors that have not enabled Science, Technology, Engineering, and Mathematics (STEM) program coordinators and faculties to introduce the teaching of RE in a systematic way, similar to the teaching of the panoply of classical STEM disciplines. Indeed, the education systems have not explicitly encouraging the teaching of RE and have not yet been considered as STEM disciplines on their own so to deserve student attention. Some of the education system plights include, but not limited to, the obvious lack of knowledge of these areas at the decision level, there are not enough teachers in the RE fields to invent new education programs, the lack of dialogue between the stakeholders (i.e., RE industry, academia, and Governmental Education Departments and other agencies having energy and environment in their portfolios). These conditions bred a situation where there is an overall lack of funding and infrastructure for systematically teaching RE in the same manner as teaching chemistry, physics, mechanical engineering,... Only portions of RE aspects are offered under the umbrella of existing classical STEM programs. To my knowledge, the US Department of Education has not called for proposals specific to teaching renewable energy and developing programs, and even it did happen, it has been not been visible to the teaching bodies and average teachers. Developing complete and independent RE curricula does not seem to be of interest. Nevertheless, few avenues have been exploited by professors within the general STEM teaching programs. On the one hand funding for such programs are pretty much constraining and on the other hand faculty rarely adventure on implementing programs for new disciplines because of the high-risk of sustainability due to funding lifetime. In addition, there are no infrastructure in the market that could prompt interest in such initiatives, except some poorly-designed systems; worse, these systems are not supported by strong enough science background.

       Almost all successful RE education programs have been set-up in engineering departments, notably Mechanical Engineering (focusing more on design and fabrication of RE devices and systems), Electric Engineering Department (focusing on concepts and infrastructure for electricity transport and management), and Materials Science Department (focusing exclusively on materials used in energy harvesting or energy management devices). Among science departments, practically only physics departments were pioneers in RE. They have infused courses on concepts on which solar energy and wind energy are based. Photovoltaics is probably the most adopted concentration in senior classes within Physics BS degree. Also, there have been Photovoltaic Concentration in graduate studies that focuses on advanced Photovoltaic theories combined with solid state physics focusing on electronic and optical properties in connection ot material structure. Community colleges is the arena where currently most of the RE education is given, while they have been late for introducing RE teaching in their technical oriented portfolios. Community colleges are not expected to do more than producing RE technicians or prepare transfer students who choose to engage in engineer career. Therefore, the delay is well understood; their participation in RE education has been prompted by the job market, and the advent of governmental incentives.

The Dynamics of RE Development is one of the Root Causes for the Delay of Broader RE Education

       This section discusses various historical facts that led to the ill-pursued effort for educating people around the world about these technologies and the underlying science, which could have been used for diffusion of RE technologies.

       Many are instinctively favorable for renewable energy, without appropriate knowledge or reference to convincing studies. The attractiveness by RE technologies is cultivated by i) the fear of upcoming energy crisis, while RE sources potentially offer free energy, ii) the general consciousness of the looming serious environmental problems, which have been blamed on burning hydrocarbons, and iii) the quest for new energy technologies in the age where electronics has shown the relevance of innovation and its great role in positively transforming societies. However, for some, RE technologies may not have a positive bottom line and whether the technology is clean or not throughout the RE device fabrication paths. Also utility companies played a negative role against the introduction of RE systems up until 2000 - 2005. These skepticisms and uneducated decisions that contributed to the delay of a broad teaching of RE sciences and technologies.

       Approaches to RE technology development, diversity of RE technologies, and immaturity of many of these technologies, are some other causes for the delay of a broader teaching of RE.

       RE project design, deployment, operation, management, and utilization, are often dependent on available funds. Historically, technology used for many massive solar energy projects have been decided by chief officers and investors rather through a thorough engineering work and optimization of existing technologies. New RE energy projects have been regarded for about three decades as opportunities for testing the technology rather than providing a solution, this is understandable but the period length ended up delaying decision on educating next generation. However, there are some exceptions; back in the eighties among developing countries, only three have understood the necessity for training the workforce and for producing scientists that will contribute in inventing and developing RE solutions.[24], [25]. Other countries, such as Arabians and Africans, are still practicing the wrong idea of “buying technology” or/and promoting the concept of “Technology Providers”, both are against a correct diffusion of RE systems, a duty that should be taken care by locals who must gain skills and understanding of the technologies, to ensure its success at large and the maintenance of the infrastructure.

       In numerous occasions, multinational companies and banks have approached local governments in MENA region and African countries to gain support and to fund installation of large RE projects built on whatever technology a foreign company has developed. This has been done regardless of the long term project survivability and usefulness of the technology to the local population. For three decades since the eighties, such approach has been adopted. The imported infrastructure and competencies for installing projects in these regions led to not employing local competencies. Understandably that practice was mostly due to project installation constrains, and because the local engineers are not trained on the imported technologies and technicians have not receive prior education on RE. As a result, in spite of the many installed mega-projects, locals have been excluded from participating in these projects, and have remained unfamiliar and even totally ignorant of the technology.

       The diversity of opinions on the approach for communicating to younger generation the massive new knowledge produced by R&D in academia and industry has also contributed in delaying designing and launching RE teaching programs. These opinions and practices varied from faculty to faculty, and from a program coordinator to another. The urgency of teaching RE also varied with Deans, VPs of academic affairs, officers in the superintendent of school systems, officers in various education departments, funding agencies. These have been observed during interviews of many of such people, while all of them, students and the general public have strongly defended the necessity for teaching RE science and technologies. However, the absence of large forum have not allowed a debate on the approaches and the means to be created in order to go about broader RE education STEM programs.

Effects of RE Science and Technology Education Insufficiency

       One of the negative impacts of not teaching enough RE in academia is the sensed lack of competent workforce and lack of engineering success in the various RE fields, in spite of the massive number of positions in the job market and the huge hiring. Consequently, RE companies find themselves forced to narrowly train workforce, precisely in the company field of activity. Discussing the issue with manufacturers and COEs showed that companies indeed suffer from the poor knowledge and luck of skills of new hires. They usually spend up to two years educating their engineers [26], so that these engineers can develop and manufacture the RE products for the company. As a result, companies pay a high price for private teaching and “a la carte” training of their technicians and engineers and their production plans are delayed. It should be noted that targeted trainings, where multi-disciplinarity is omitted, is an extremely poor way for educating future generations. It will lead to catastrophic long term impact on the workers and technicians as well as the economy. Without a strong RE science and technology foundation and a complete STEM knowledge related to the area of specialization, workers can neither escalate the position ladder within their company nor can they change or convert their jobs. Thus, this category of workforce remains at risk in a dynamic and global economy where competition is high. Also practical knowledge is far from enough for cultivating future inventors, engineers capable of tuning or improving the technology, and entrepreneurs who can push forcefully the success of renewable energy enterprise and avoid bankruptcy [27],[28],[29].

       There have been unfortunate phenomena that worked against RE diffusion, such as the observed rerouting current RE technology for today needs to developing non-sense applications. This wide spread phenomenon is first due to lack of knowledge at various scientific levels, but also due wrong policy of utility companies. They have been steering RE towards using it to preserve the legacy energy sources and technologies. As a consequence many technologies are being wrongly designed and installed. Furthermore, as RE technologies are subject to quick transformations, which have been seen over the past four decades, the ill-prepared workforce is not a guarantee for the success of the new RE technologies. This is suggested to be one of the reasons for the slow pace of diffusion of RE technologies over the past two decades, in spite of the huge technological success of photovoltaic and solar thermal energy, one of the major RE components. Also, one must not forget the struggle of RE technologies to become competitive in face of the low-cost energy extracted from burnt oil. Policy makers have not yet make plans to preserve hydrocarbons for other high value applications and to opt towards substituting the legacy oil based technologies by modern RE technologies. Production of high value materials out of hydrocarbons, such as ingredients for enhancing food production, pharmaceutical materials, materials for construction, carbon electronic materials, etc. suggest that we leave out the rapid waste of these hydrocarbons in powering cars and the like, and vigorously opt for speeding up the diffusion of RE technologies. The hope now is in the younger generation; we must educate them so they understand the real potentials we have, and how to create a sustainable world, and how to preserve a healthy environment.

New RE Curriculum and Laboratory Equipment

       Teaching RE either in Engineering Departments or in Community Colleges have been relaying on real size infrastructure (real solar water heater, heat storage tank, real concentrator troughs, wind mills,…). These induce enormous limitations for doing experimental testing that allow verification or reconstruction of the fundamentals on which the technology is based. That approach is certainly beneficial for exposing students to real size systems and to do measurements in such contraptions as they are installed (maybe with minor modifications). However, such systems do not allow to go further than the practical understanding of the used systems. That strategy does not allow grooming engineers for producing innovative concepts and improving RE technologies. Likewise, teaching physics of RE without proper laboratory infrastructure, is a clear impediment for doing measurements and in depth physics studies of the technology, the material used to construct the device (e.g., photoconductivity of semiconductor, textured absorber, multi-layer reflector, …), or the energy harvesting device (third generation solar cell, quantum dot based device, perovskite solar cells,…).

       Due to the above limitations in teaching RE, we have initiated the development of RE teaching programs at various levels. In fact, the initiative is the result of my long experience with teaching RE within my physics and materials science teaching. My focus was essentially on photovoltaic materials, devices, and systems. Additionally, for some undergraduate physics courses, I have expended teaching many RE areas. The initiative has been further promoted after receiving a National Science Foundation Award. The intention is to complete the development of a new curriculum on Solar Energy and to promote it within schools and school systems. The curriculum has various components and is modular so to facilitate various combinations that fit a wide range of teaching objectives. The program is suitable for Electrical engineering, Mechanical engineering, Energy engineering, Industrial engineering, Materials science engineering, Applied physics, and Technical Colleges. Likewise, since we strongly believe that younger generation must be educated in the energy and environment science and technology, we intend to develop a simplified version for high schools. We are also planning to generate a version adapted to professionals who are in the business of Solar and Wind Energy. Our goal is not to just survey opinions through this forum, but rather to understand opinions of students, teachers, education experts, and industry and to probe customers’ expectations.

Public Opinion Matters for Directing the “Teaching of RE for Next Generations”

       Concerning the utilization of RE technologies, a clear divergence between scientists’ views and those of businessmen, project designers, managers, and investors is apparent. These stakeholders are on the ground and are seeing different realities from RE scientists. One of these realities is the funding constrain that forces project developers to adapt RE to older technologies, and not the opposite. For examples, based on demonstrated ideas and pilot generated data, scientists see that rooftop photovoltaics and solar thermal energy are the most appropriate for powering cities and suburbs. However, current projects focus on installing several hundred of megawatts and gigawatt projects to power towns. Products and technologies for the optimal rooftop solar approach are already on the market. The remarkable and undeniable advantages of rooftop (and likewise the PVIB) technologies are the facts that they do not take over fertile lands, they are the more directly connected to appliances, thus, they provide the highest overall efficiency and the least waste in terms of energy as well as infrastructure. They also follow the simple idea of “Producing Renewable Energy right close to the appliance in need for that energy”. Also scientists see the extensive usage of Large Batteries to store energy from RE sources is a wrong concept. Similarly, maintaining the idea of energy transportation defies, the principle of “RE sources is a diluted form of energy and should be used where harvested”. The current practice, supported by utility companies, is to maintain the Electric Grid, a way to keep their “business as usual”. However, that is done at the expenses of a correct development of the emerging RE technologies. In simple terms, we are seeing, on the ground, a non-sense practice. Continuing in that illogical path will potentially reduce the chances for sustainability. Had we had well educated engineers from the start, we may not had followed that wrong pathway, which is risky for the entire RE approach. Engineers are not able to disconnect from the useless classical electric grids, and are neither promoting the concept of “local-grids” and “micro-grids”, nor the idea of complementarity of RE technologies. While it is true that energy-mix is complicated to manage (using the current interfacing technologies), it is till the optimum path. For instance, coupling photovoltaics with solar water heater, photovoltaic with wind energy, photovoltaics with CSP will do much better than currently installed projects. These energy mix solutions do not require energy transport through the grid, minimize wastes, and prevent unnecessary use of heavy infrastructure (grid, batteries,…) and related cumbersome operation. The need for batteries must be reduced to an extremely small size, just for limited back-ups (system starters, controls and computers), but never for powering appliances.

       “Everybody loves clean energy”. I heard it countless times. But many support RE without a strong argument or not based on sufficient knowledge, or project design optimization. Moreover, many don’t know how to go about acquiring the technology and utilizing it. Among engineers, each has a certain view on how to approach the use of RE technologies. Unfortunately, many do uneducated choices, because there is no separation between RE and the energy legacy technologies. In the context of continuous development and changes of RE technologies, a contrast between the benefits of the various technologies and their operability is not yet determined. This is due to the wide range of technologies that keep emerging and the dynamics to enter the market.

       Whether one is skeptical or proponent of RE, whether he/she is a teacher, student, or businessman, and whether he/she has been teaching renewable energy, planning to introduce new courses in existing programs, it is important to participate in an inclusive debate about the delay in RE teaching and its cause roots. After two decades in putting together various RE start-ups and the difficulties and success stories, it is judicious that businessmen and sponsors enter the debate to guide decision makers through their learnt lessons. Their practical experiences will enlighten the best pathway for educating next generation, and the type of needed education, and phases to achieve that goal.

       Our lifestyle and the quest for increasing food production, as the world population increases, are the culprit for the generation of energy and environmental crisis. Humanity survival depends on finding new clean energy sources and on the sober use of energy to maintain a clean environment. It is timely to clarify through diverse forums the role of teaching renewable energy in solving these crucial problems and generate game changing solutions. Knowing the diversity of RE energy sources and thus technologies, and the inevitable concept of energy-mix when using RE sources, general discussion are important, but particular interest of stakeholders are equally important for a complete discussion. For instance, it is necessary to find answers to some critical questions like those presented in the Appendix.

References

[1] Gail Parson, Jeff Benzak, Grant Carlisle, Bob Keefe, Peter Voskamp, Lauren Kubiak, Clean Jobs America, A comprehensive analysis of clean energy jobs in America , Presented by Environmental Entrepreneurs, March 2016.

[2] Robert K. Willardson, Solar cells, Academic Press, (1966).

[3] Harold J Hovel, Semiconductors and semimetals. Vol. 11, Solar cells, Academic Press, (1975).

[4] Alan Fahrenbruch, Richard Bube, Fundamentals of Solar Cells: Photovoltaic Solar Energy Conversion, Elsevier, ISBN0323145388, 580 pages,(2012).

[5] Charles E. Backus, Solar cells, IEEE Press, 504 pages 1976

[6] André Laugier, Jean-Alain Roger, Les Photopiles solaires : Du matériau au dispositif, du dispositif aux applications, Technique et documentation ISBN-10: 2852060957, 307 pages (1981).

[7] K.L. Chopra, S.R. Das, Thin Film Solar Cells , Springer Science, 607 pages, (2013)

[8] The "Willardson and Beer" Series, Metals and Semiconductors, Academic Press, since 1966

[9] Jenny Nelson The Physics of Solar Cells, World Scientific Publishing Company, 384 pages, (2003).

[10] Martin A. Green. Third Generation Photovoltaics: Advanced Solar Energy Conversion, Springer Science & Business Media, 160 pages (2003).

[11]  Stephen Fonash Solar Cell Device Physics, Elsevier, ISBN: 0323154638, 352 pages (2012).

[12]  Tom Markvart, Luis Castaner Solar Cells: Materials, Manufacture and Operation, Elsevier, 556 pages (2004).

[13] Ben Streetman, Sanjay Banerjee   Solid State Electronic Devices, 6th Edition Prentice Hall; 6 edition ISBN: 013149726X 581 pages (2005).

[14]  John R. Howell Solar-Thermal Energy Systems: Analysis and Design McGraw-Hill College ISBN-10: 0070306036 406 pages (1982).

[15] John R. Howell, Richard O. Buckius  Fundamentals of Engineering Thermodynamics, McGraw-Hill College; ISBN-10: 0070796637, 697 pages  (1986)

[16] John R. Howell , M. Pinar Menguc , Robert Siegel  Thermal Radiation Heat Transfer   5th edition by Howell, John R - Siegel, Robert - Menguc, M Pinar (2010).

[17] John R. Howell, Fundamentals of Engineering Thermodynamics, McGraw-Hill College; ISBN-10: 0079113893 (1992).

[18] Philip S. Schmidt, Ofodike Ezekoye, John R. Howell, Derek Baker  Thermodynamics, Text plus Web: An Integrated Learning System ,  Wiley ,  ISBN-10: 047114343X, 480 pages (2004).

[19]  “Hands On Photovoltaic Experience" program, National Center for Photovoltaics,   

https://www.nrel.gov/pv/hands-on-photovoltaic-experience.html

[20] The “Solar University-National Lab Ultra-Effective Program”, National Center for Photovoltaics, https://www.nrel.gov/pv/sunup.html .

[21] National Joint Apprenticeship and Training Photovoltaic Systems, Third Edition (Book 3) Amer Technical Pub, 3 edition ISBN-10: 1935941054, 502 pages (2012).

[22] Lapo Pop,  Dimi Avram, The Ultimate Solar Power Design Guide: Less Theory More Practice (The Missing Guide For Proven Simple Fast Sizing Of Solar Electricity Systems For Your Home or Business) Digital Publishing Ltd, 230 pages, (2015).

[23] Duke's Fuqua School of Business https://www.fuqua.duke.edu/

[24] Among developing countries, Mexico, India and Tunisia have launched photovoltaic programs as early as mid-seventies.

[25] Tunisia has been pioneer in solar energy R&D through its “Programme National de Recherche Scientifique (PNR)”, which was launched in 1975 in collaboration with the European Economic Community (EEC).

[26] Several private communications, for instance with Dr. Mick Humphreys, CEO of Apricus Solar.

[27] SOLENEA is one among many cases that had filed for Bankruptcy. Despite the strong engagement of the US government failed not only because of the mismanagement but also because of the technology. It was a strong set back for solar energy.

[28] World Solar failed a large contract, despite an excellent negotiation for remedy. Testemony of Daniel Shugar in EISA meeting of 2017. NEXTracker US ITC Testimony, Aug 15, 2017

[29] Discussion of Dr. Karoui about the World Solar case with Daniel Shugar CEO of NextTracker.