Category Archives: EuroSun2008-9

ITALY’S ARCHIVE ON THE HISTORY OF SOLAR ENERGY

C. Silvi

Gruppo per la storia dell’energia solare (GSES) — Via Nemorense, 18 — 00199 Rome, Italy

E-mail: csilvi@gses. it

Abstract

This paper reviews research and organizational activities for the creation of the Italy’s Archive on the History of Solar Energy, a project started in 2003. The project’s main purpose is to preserve the Italian heritage of solar energy use, creating a digital archive accessible via the Internet. The first branch of what will be a geographically distributed archive has been taking shape over the past years at the Luigi Micheletti Foundation and the Eugenio Battisti Museum of Industry and Work (www. musil. bs. it) in Brescia, in northern Italy. An important step forward came in 2006, when the “Italian National Committee ‘The History of Solar Energy’” (CONASES), a multidisciplinary non-profit entity, was established by the Italian Ministry for Cultural Heritage and Activities, following a proposal by the Group for the History of Solar Energy (GSES, www. gses. it). In 2008, a cooperation agreement on a nationwide survey of sources on solar energy, signed between the State Archives Department and GSES, opened up new prospects for further development of the Archive. Examples of archives and documents already collected and under study are provided. The paper also shows that the Solar Archive project is already rewriting Italian solar energy history.

Keywords: solar archive, solar history, solar pioneers, solar architecture, solar cities,

1. Introduction

It often happens that we think of solar energy (its direct and indirect forms, wind, hydro, forests and other biomass) as an aspect of our modern world, although it had powered everything on earth until 150-200 years ago, when its fossilized forms — coal, oil and gas — began to gain sway.

For thousands and thousands of years the use of solar energy shaped human settlements and cities, farming and forestry, architecture and buildings, landscapes and territories, religious beliefs and cultures, social relations and lifestyles on Earth — in a word, whole civilizations. The use of solar energy is thus an age-old experience marked by milestones on the path that led human beings to artificially convert it into other useful forms of energy and goods: food, construction materials, heat, fuel, daylight and, more recently, electricity, which has been, is and will continue to be a fundamental part of modern life.

Discoveries in the field of solar energy use, made during what I would propose to call the primitive or ancient solar age — when solar was the sole source of energy — still have a major role in our daily lives. This is well exemplified by the Romans’ discovery of windowpane glass in the first century A. D., to bring daylight inside buildings and at the same time prevent cold and winds from entering. Today millions upon millions of windows provide daylight to homes and workplaces all over the world, thereby saving on artificial light produced with electricity generated by fossil and nuclear fuels.

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An additional example is provided by farming and agriculture. From the earliest civilizations they were powered, and continue to be powered today, by solar energy as the primary and principal energy source.

These technologies and discoveries, which have evolved throughout the centuries, are still of greatest importance in our daily lives. It is as if an ancient renewable-solar-energy soul were an essential part of our modern world, taken for granted and not accounted for in official energy-use and economic statistics. Therefore, the history of solar energy can hold important lessons for our own times, when humanity is beset by a growing number of problems, closely related to the use and availability of energy.

Since 2000 GSES, a volunteer not-profit organization formed by experts and scholars from various technical fields, has been promoting and organizing initiatives aimed at producing a systematic history of the use of solar energy. In this paper, the focus is on modern or future solar age, currently sprouting from the pioneering work on solar energy done over the last centuries, in particular during the last 150-200 years.

Renewable energy education in Armenia: going for imperative

1.3 How educated we are

The availability of educated and trained people at all levels and in all engineering disciplines is a crucial factor for the successful implementation of any programme towards sustainable use of energy, as well as preserving the environment. Unfortunately, at current stage the universities of Armenia are not involved in specific education programmes to prepare specialists and professionals in renewable energy field. Some disciplines within the general power engineering programmes though incorporate basics for renewable energy. An introductory and non-mandatory renewable energy classes are incorporated in very few universities’ curricula. However, no

institution is actively pursuing teaching activities in this area at both bachelor and master degrees. Few universities are engaged in education and research and development in solar energy, such as State Engineering University, State University, and American University of Armenia. Despite the fact that with increasing pressures of fossil fuel scarcity and adverse environmental impacts of their use, more countries make efforts towards providing renewable energy and environmental education, Armenia has not been taken this seriously and no real efforts have been made to provide renewable energy and environmental education.

Education as a way to get public (not only academic institutions and students) to understand and be aware about the benefits renewable energy can offer is a crucial component. In this regard, a few efforts have been taken to bring attention of general public and schools community on renewable energy basics. A number of programs to promote renewable energy in Armenia were implemented since mid 1990s. Specifically the education and public awareness projects included small scale publications for general public [1], [2] and workshops or seminars under donor funded projects [3]. In 2004 SolarEn, LLC in association with UNDP, ASE/USAID, Armenia Tree Project NGO and Ministry of Education has developed and implemented a project that included preparation of Renewable Energy Poster and Instruction Manual for teachers [4]. The posters and manuals were distributed to all state schools in Armenia (over 1400). The project envisaged provision of general information on renewable energy technologies as well as the specific technologies applicable for Armenia. It also indicated renewable energy projects already implemented in Armenia. The poster is easily understandable to pupils, while the teachers’ manual provides key information in technical and economic aspects as well as environmental benefits. The project was unique in terms of the approach — delivery of basic knowledge to young generation and teaching teachers through the all state schools. Measurement of results was not envisaged under the project. It was agreed with the Ministry of Education to include provision of basic knowledge through school curricula under “General Physics” classes. However, non-mandatory nature of such introductory approach did not ensure the classes be successful. Finally, general public and potential consumers as well as communities, businesses and decision makers at state agencies are unfamiliar with the benefits of renewable energy.

Development of an educational kit for teaching photovoltaic. generators interconnection modes and reverse bias effect

M. Perez-Garci’a1* , J. L. Bosch1 and A. Fernandez2

1 University of Almeria (UAL), Department of Applied Physics, E-04120 Almeria, Spain
2 CIEMAT-PSA E-04200 Tabernas (Almeria), Spain
Corresponding Author, mperez@ual. es

Abstract

This work describes the configuration and the performance of a small scale device aimed to be used as educational tool to support the contents related to the interconnection modes in a PV generator as well as to visualize the effect caused by the partial shading of one or several of its cells. The device consists of three main components: a set of m-Si cells, a variable light source and a load simulator connected to general purpose electrical meter. All the elements of the device are low cost and easily available in electricity and electronics laboratories. The performance of the device allows to draw I-V curves for each one of the cells and their parallel — series combinations under controllable illumination levels. This educational kit has been developed for its use in the Laboratory of Energy and Environment of the Department of Applied Physics of the University of Almeria.

Keywords: solar cells, interconnection, mismatch, hotspot

1. Introduction

The understanding of the solar cells characteristics as electricity generators is one of the key topics in any course on photovoltaic solar energy fundamentals or applications. In this sense, the students might get used to the solar radiation and temperature dependence of the solar cells parameters and, as consequence, their energy yield in function of local climate as well as they should be also able to extract complementary information from the shape of I-V curves as, for example, that requested for optimizing PV systems performance by the application of the maximum power tracking concept.

The step from individual cells characteristics to PV modules, arrays or plants characteristics is immediate because it consists essentially in the series-parallel combination of single elements until matching the voltage and/or current levels requested for the inverters or any other final PV system component. This combination, although in practice is not usually further analyzed by the students once PV system design is concluded, must however be still carefully studied because the lack of equilibrium between interconnected parts or strings can cause a serious problem in the whole PV generator under certain conditions. The above is provoked by two main reasons [1]. The first one, intrinsic, is the finite manufacturer’s tolerance in cell characteristics and, consequently, the eventual interconnection of non exactly identical elements. In an PV array, in these circumstances, the output power of the combination is less than the sum of maximum output power of its constituents. The second reason arises due to external causes as accidental impacts provoking the partial or full opening of a string due to cell

cracking and, especially, the shadowing of a certain fraction of the generator because predictable (near buildings, trees, mast,…) or unpredictable (bird droppings or fallen leaves) sun radiation blocking.

All the losses in the PV generator performance caused by the above are called mismatch losses As greater the difference between mismatched parts in regard to the rest of the generator elements, the higher losses because the output of the entire PV generator is determined by the solar cell with the lowest output. In addition to this undesired effect, when the difference exceeds certain level, the unbalanced elements in the generator become reverse biased, acting as loads instead of generators and, if not appropriate protection exists, overheating of these parts (hot-spot effect) can arise and, in severe cases, the system can be irreversibly damaged [2].

The methods for correcting fault tolerance for the electrical mismatch consist on limiting of component malfunctions by redundant circuit design together to on site extensive modules checking. This increase the installation time and costs, specially in multi-MWp plants, but, usually, the retrieved energy justify this extra effort. On the other hand, the hot spot effect in the partially shadowed solar cell arrays is minimized considerably by installing bypass diodes connected in parallel, but with opposite polarity, to the eventually affected solar cell. Many studies have been done to optimize the number and configuration of these diodes in PV modules and generators [3-4]. The performance of by-pass diodes is based on the following: under normal operation, each solar cell will be forward biased and therefore the bypass diode will be reverse biased and will effectively be an open circuit. However, if a solar cell is reverse biased due to the a mismatch in short-circuit current between several series connected cells, then the bypass diode conducts, thereby allowing the current from the good solar cells to flow in the external circuit rather than forward biasing each good cell. Although modules manufacturers and PV systems designers are used on hot spot prevention, the new needs as bigger modules for grid connected applications and the requirement of the absence of connection box for architecturally integrated PV applications in windows or roofs, make necessary case specific configurations to protect the systems against this risk.

The effect of unbalanced cells in PV generators curves can be easily visualized by a simple a procedure and its study can provide to the students a large amount of specific skills on cells electrical performance. The equipment proposed in this work consists of a) a set of cells prepared to be manually interconnected by leads in different modes c) a set of controllable light sources, each one linked to specific cell and d) a load simulator able to provide corresponding I-V pairs to draw characteristic curve of each cell.

2. Theoretical basis

Building Italy’s Solar Archive: the starting point in 2003

The idea of Italy’s Archive on the History of Solar Energy began to develop within GSES in 2003, with the main purpose to preserve and make widely available the Italian heritage of solar energy use. Two main actions were initiated: the preparation of a “Directory of Italian Activities and Bibliography of Significant Literature” regarding the period prior to the first oil shock of 1973 and the identification of overlooked archives at universities and research centres or privately owned [1].

Key information to begin a narrowly focused investigation was found in the World Directory on Applied Solar Energy Research, published and distributed in 1955 by Stanford Research Institute for the Association for Applied Solar Energy (AFASE), the precursor of today’s International Solar Energy Society (ISES) [2]. This publication, which lists approximately 4000 references relevant to 27 countries and covers 17 different topics, from architecture to bibliographies, from furnaces to heat storage and systems, includes a dozen references regarding Italian activities and publications prior to 1955.

Other citations and bibliographies that were useful in guiding our historical research during this early phase were found in books, such as “L’energia solare e le sue applicazioni (Solar energy and its applications)” by Righini and Nebbia [3] and in articles, magazines and scientific journals published in the late 1800s and early 1900s, such as IlMonitore Tecnico (The Technical Monitor), Scienza e Tecnica (Science and Technology), L’Ingegnere (The Engineer), Il Sole (The Sun).

We also looked at books by international authors, which had been translated into Italian. For example, according to Rau, although Italy is “Ilpaese del Sole” (The country of the Sun), there were few Italian representatives among the most innovative solar energy pioneers. Those who were interested in solar energy, according to Rau, ‘made only marginal contributions by adding to or improving technologies developed elsewhere’ [4]. This statement, as we will see later is not correct.

The initial branch of the solar archive started to take shape in Brescia, in northern Italy, at the Luigi Micheletti Foundation and the Eugenio Battisti Museum of Industry and Work (www. musil. bs. it) [5]. In 2002 the Giorgio and Gabriella Nebbia collection on a range of environmental topics was donated. Nebbia’s collection contains one of the largest Italian archives on solar energy of the 1900s. In 2005 the heirs of Giovanni Francia (1911 — 1980), who was the first person ever to apply the Fresnel reflector technology principle in real systems, both linear and point focus, donated his personal archive.

The creation of Italy’s Solar Archive made an important step forward in 2006, when the “Italian National Committee ‘The History of Solar Energy’” (CONASES), a multidisciplinary non profit entity was established by the Italian Ministry for Cultural Heritage and Activities, following a proposal by GSES. Funding support by CONASES contributed to intensify research of other private archives and documentation that belonged to Italian solar pioneers cited in literature, such as Gaetano Vinaccia (1889 — 1971), Vittorio Storelli (1911 — 2003), Ferruccio Grassi (1897 — 1980), Daniele Gasperini (1895 — 1960). These archives were donated to the Museum by their heirs and have already been partially inventoried and can be consulted at www. musil. bs. it.

CONASES also supported specific research on patents done by Martelli and Merola in 2006-2007 at the Central State Archive, where documentation produced by the Italian central institutions has been preserved since 1861, the year of Italy’s unification [6]. The research was carried out on the Patent collections, which are among the better-structured collections preserved at the Central State Archive. These collections are made up of 891,000 folders that document more than one century of activity of the Italian Patents and Trademarks Office of the Italian Ministry of Trade and Industry, today’s Ministry of Productive Activities. The research was focused on collection of patents dealing with Inventions, which is made up of 620,000 folders dating from 1855 to 1962, and whose content is available only in print format. Each patent application includes the description of the patent, as well as machine and flow chart drawings. As of March 2008, 157,113 folders related to the period from 1855 to 1916 had been examined and 392 patents associated with solar energy were identified, corresponding to 2.5% of all patents.

Non-Italians, mainly from European countries, such as Austria, France, Germany, Portugal and Spain, also authored several of these patents. Among the European patent authors were well — known pioneers such as the French scientist Augustine Mouchot (1823 — 1912) and the Portuguese Manuel Antonio Gomes Himalaya (1868 — 1933).

Подпись: Fig. 3 . Himalaya patent’s application to collect solar energy at high temperature, submitted in Boulogne (France), Aug. 12, 1901, (courtesy Italian Central State Archive).
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Подпись: Fig. 4 . Alessandro Battaglia patent’s application on a “Collettore multiplo solare, Multi Solar Collector” registered in Genoa (Italy), Oct. 13, 1886, (courtesy Italian Central State Archive).

Among Italian patent authors only a few can be easily identified in literature. Most of the applicants, who anticipated important technical concepts and solutions, are unknown. The case of Alessandro Battaglia (1842 — ? ) from Acqui Terme, author of a Multi Solar Collector, made up of an array of 252 mirrors individually aimed at a receiver, provides a good example. He applied for a patent on September 30, 1886. Several research efforts to learn more about him, have thus far resulted in determining only his time and place of birth. This shows that it can be difficult to find additional information regarding patent authors identified at the Central State Archive. This type of research has also shown to be highly time consuming.

Martelli and Merola presented the research results at a seminar promoted and organized by GSES and CONASES in cooperation with the Central State Archive on April 4, 2008. Detailed information about the seminar can be found at www. gses. it.

Experience to consider

Many countries’ leaders stress the need for strengthening human resources for improving the quality of energy. They urge their governments to focus efforts on promoting renewable energy technologies and pledged international community with commitment to strengthen national energy sector with renewable energy technologies. On one hand, most of developed countries succeeded in their efforts and currently renewable energy contribution in those countries are significant and the industry in general is on the stage of exponential growth. The same is true for those developing nations whose governments have taken concrete steps towards harnessing renewable energy resources for socio-economic development of their country. On the other hand, many efforts in last years by a number of states and organizations have yet to achieve a renewable energy marketplace. Experts view this was a consequence of three fundamental things: (i) first, not achieving the critical messages and motivators needed to affect business and consumer behavioural change; (ii) second, despite widespread publicity and media coverage of the subject, most consumers are not aware of any compelling reason to choose renewable energy; (iii) third, not effectively leveraging the investment and incentives as most available research suggests that price is still the single most important factor in selecting a renewable energy comes with a premium price; (iv) fourth, the target audience is diverse and complex [5].

The demand for skilled and knowledgeable labour throughout the renewable energy industry and increasing interest from students has spurred several educational institutions across the U. S. and Europe to add undergraduate or graduate degrees, or certification programs in renewable energies to their curricula.

Obviously as a part of obstacles is that benefits of renewable energy have not clearly communicated with the public, customers and decision makers. Educational quality, measured by what people know, has powerful effects on individual earnings, on the distribution of income, and on economic growth [6]. The role of education and its quality becomes important and crucial not only in general terms but in this specific area as well.

In fact, what most people like about their utility is the total absence of having to think about it at all. For those who have an understanding of options, reliability is then a worry. Concern about a change to an unfamiliar source represents a significant barrier to switching that must be addressed and overcome.

Another key factor is that education supports market and industry development in renewable energy field. For an economy, education can increase the human capital in the labour force. It can also increase the innovative capacity of the economy, knowledge of new technologies, products, and processes promotes growth. Education facilitates the diffusion and transmission of knowledge needed to understand and process new information and to implement new technologies devised by others, again promoting growth [7].

Combination modes of solar cells

One individual silicon solar cells provides under nominal conditions, on average, in the order of 600 mV and 30 mA/cm2. Solar cells are then rarely used individually. Rather, cells with similar characteristics are connected and encapsulated to form modules which, in turn, are the basic building blocks of solar arrays. Starting from individual solar cell load curve, the curve of the combination of certain number of cells will preserve the basic series-parallel interconnection laws (Figure 1). Voltage for serially connected elements is the sum of partial voltage across the individual cells and the same current flows through every solar cell. If higher currents are demanded in a system, these can be obtained by parallel connection of the individual strings. In a parallel connected configuration, the

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voltage across each solar cell or solar module is equal, while the total current is the sum of all cell or module partial currents. At present, PV generators in grid connected systems work in the range of hundreds volts and amperes.

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V

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Fig. 1 Interconnection modes of identical solar cells

The work ahead for the creation of Italy’s Archive on the History of Solar Energy

The results of the research done during the 2006-2007 period at the Central State Archive on the Patents and Trademarks Collections have secured new commitments. The Italian State Archives Department and GSES signed a cooperation agreement and established an ad hoc working group (Solar Archive Working Group) in 2008 to perform a nationwide survey of sources and create a multimedia database. The work already done in the Central State Archive’s Patents and Trademarks Collection, and by GSES in the private archives of Italian solar energy pioneers, has produced useful technical and scientific results that can provide a starting point for this survey, which might well focus first of all on sources regarding patents and trademarks contained in the State Archives and in private archives.

The work ahead for Italy’s Solar Archive was illustrated by Terenzoni from the State Archives Department at the seminar on April 4 [7]. She addressed the main aspects related to archival sources and tools for historical research on solar energy in Italy. Italy’s archives contain miles upon miles of shelves filled with all kinds of documents, information and data produced by government bureaus and agencies, public and private enterprises, and individuals. Very often their contents are accessible only by means of “traditional” systems. To consult documents regarding a particular subject, it is sometimes necessary to be familiar with, or reconstruct, the history of the institution or the biography of the individual that produced the documents, as well as the

circumstances that led to their production, drawing one to look into all the ramifications (real or suspected) of a given activity.

The archival sources are heterogeneous and the existing research tools are complex and not easy to handle, and will thus require some terminological-control tools, for instance a glossary and dictionaries of standard terms, which can enable users to search through databases by keywords and identify descriptors. Moreover, language and terminology evolve; therefore, in order to produce a truly useful search tool it will be necessary to clarify linguistic ambiguities and the relationships among terms that belong to the same family.

The Solar Archive Working Group has already started looking into this. The systemic aspects of solar energy is guiding the terminology work, both when we think of solar energy resources on earth as well as when we think of solar know-how and technologies that can convert those resources in energy forms useful to us (food, heat at low, medium and high temperatures, daylight, fuels, electricity, materials etc.).

Inputs to clarify linguistic ambiguities and relationships among terms will also come from the material contained in the archives, documentation, and bibliographies collected thus far.

Going for imperative

More and better education is a prerequisite for rapid development of renewable energy industry, growth of the businesses and markets. Education stimulates economic growth and improves people’s lives, and empowers individuals and governments make right decisions and support renewable energy development. On the other hand, nation’s commitment to education is both demand-lead and supply-lead [8].

For example, with surging interest from the residential construction sector and new requirements for utilities to generate portions of their energy from renewable sources, the renewable energy industry in the U. S. is flourishing, and job opportunities are increasing. As the industry grows, however, a workforce shortage is expected [9].

In Armenia, education about renewable energy has mostly been limited to learning tracks and seminars at industry tradeshows and conferences. Clean energy should start playing a significant role in people’s lives, and thus teaching of renewable energy should be emphasized in education and public awareness campaigns. Education in renewable energy fields should become a priority for the state. Some curriculum developers and teachers in both schools and academic institutions should incorporate renewable energy related activities in their curricula.

As mentioned earlier, one of barriers to mainstream adoption of renewable energy systems is the lack of awareness among consumers. Many consumers have heard at least some reference to renewable energy at various times in their lives, but they do not know how to incorporate it into their daily lives and they lack the necessary knowledge to purchase and utilize renewable energy technologies.

"There are a lot of great engineering and architectural firms that want to do things with energy but aren’t quite sure what to do with them. We need to educate more people," says Michael J. Newtown, director of the State University of New York-Canton’s (SUNY-Canton) Alternative and

Renewable Energy Applications degree program. "As engineering and architectural firms come together, there really is a need to educate the populace on how renewable energy gets used, and where it gets used, and what’s the best application" [9].

At this stage, the limitation of reaching the set targets for renewable energy development is indeed related to education and training. Per words of Dr. Ad van Wijk, Chairman and Founder of Econcern (the Netherlands) “we developed many scenarios for the integration of wind power and energy efficiency. The reality has always exceeded the most optimistic scenarios. The only thing that is limiting goals is a shortage of skilled people. We have train and educate in a range of skills and technologies that are not traditionally taught in colleges and universities. It is a real challenge”

[10] .

The importance of general public education is proved by lack of understanding by a consumer of the technology. While, numerous surveys have confirmed widespread public interest in renewable energy, hurdles identified by the California Energy Commission (CEC) included [11]:

• lack of awareness about choice and how to switch to new, and fear of switching and losing reliability

• price premium for renewable energy with return on the investment unclear

• lack of knowledge regarding the environmental impacts of electric generation and the benefits of renewables

• lack of knowledge regarding the equipment and its technology application and availability

• a perception that the installation processing is difficult and complicated

• difficulty in finding a qualified installer and lack of trusted references from (friends, neighbours, etc.) that have installed their own solar or wind systems.

Mismatch effect

Подпись: Fig. 2 Parametric representation of PV cell generator load curve

In general terms, given a temperature and irradiance values, the load curve of a conventional solar cell can be represented by a classical parametric model (Figure 2) in which it can be distinguished 3 operation zones in regard to the load nature. As shown, cells being operated in reverse bias mode can suffer structural damage. Mismatch appears when the electrical parameters of one or several solar cells are significantly altered from those of the remaining devices and being altered the resulting curves shown in Figure 1. The alteration of a cell can consist, as advanced, of slight parameters modification due to the tolerance in manufacturing process or a change in its operating conditions in regard to the rest because the blocking of radiation impinging the cell surface.

For simplicity, we will restrict the description of the influence of mismatched parts to a circuit constituted by 2 single cells, A and B (Figures 3 and 4), being the cause of the unbalanced behavior the shading of cell B.

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For a series interconnection, Figure 3 (right) shows how open circuit conditions for A+B generator are no highly affected by mismatching of cell B. However, as the current through the two cells must be the same, the overall current from the combination cannot exceed that of the poor cell. Therefore, the current from the combination cannot exceed the short-circuit current of the poor cell. At low voltages where this condition is likely to occur, the extra current-generating capability of the good cells is not dissipated in each individual cell (as would normally occur at short circuit), but instead is dissipated in the poor cell. An easy method of calculating the combined short circuit current of series connected mismatched cells is to consider that the current at the point of intersection represents the short circuit current of the series combination (VA+VB=0).

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For parallel connected cells, at low voltages, there is no real problem with mismatch as the currents just add and the total current is always higher than the individual cell currents. However, the resulting open circuit conditions are highly affected because the addition of mismatched cell B reduces the open circuit of A+B generator to a lower value in regard to the original one. A simple method to calculate the resulting open circuit voltage in this situation is to consider according individual cells curves that the above will occur when iA + iB = 0,as shown in Figure 4 (right).

Fig. 4 Mismatching in parallel connected cells

Examples of archives and documentation collected

Since 2002, more than 15 privately owned archives as well as those belonging to solar pioneers of different standing or their heirs, have been located or simply identified. It has been a time consuming endeavour. In fact, in the matter of just a few decades, the traces of people and events can be lost. For solar energy it is even more difficult to find firsthand witnesses with specific knowledge of projects as well as to locate and consult private archives and documentation produced just a few decades ago. While interest in solar energy has for decades been repeatedly left behind, and with it also its history and the history of its pioneers and advocates, interest has recently been growing again worldwide.

At any rate, this has been our experience in Italy, where interest in solar energy history and in the creation of Italy’s Solar Archive increased at an institutional level essentially over the last three years, also due to the pioneering work done by the Eugenio Battisti Museum of Industry and Work (www. musil. bs. it) in Brescia and GSES [8].

This museum was promoted by the Luigi Micheletti (www. fondazionemicheletti. it) and Civilta Bresciana Foundations. Branches have been established at multiple locations, based on a program agreement among the Lombardy Region, the city and the province of Brescia, and many other public and private organizations.

Thanks to a decades-long acquisition policy, the museum owns large collections of objects and documents related to the history of industry and work on the local, regional and national levels.

The collections concern everything from motion pictures to printing and textiles, textile machinery, energy, large engines, machine tools and metallurgy.

The collections that deal with energy were assigned to three new branches of the museum, one in Brescia, another in Rodengo Saiano (Franciacorta) and the third in the Camonica Valley, at a

former hydroelectric plant from the early 20th century in Cedegolo. This last branch opened on September 13, 2008 [9].

Information about donation, inventory status, and references of a few examples of solar archives currently preserved at Eugenio Battisti museum are provided in Table 1.

Table 1 . Some of the solar archives donated for the Italy’s Solar Archive

Private archive of

Donated by

Inventory status

References

Giorgio and Gabriella Nebbia (1926 — )

G. and G. Nebbia (2002 )

To be completed (as of 2005, 462 pages)

Online at www. musil. bs. it

Giovanni Francia (1911 — 1980)

Heirs (2005)

To be completed (as of 2007, 216 pages)

[10] [11] [12]

Vittorio Storelli (1914 — 2005)

Heirs (2006)

Not yet started

[14]

Gaetano Vinaccia (1889 — 1971)

Heirs (2007)

To be completed (as of 2008, 14 pages)

[13]

Ferruccio Grassi (1897 — 1980)

Heirs (2007)

To be completed (as of 2007, 8 pages)

[15]

Daniele Gasperini (1895 — 1960)

Heirs (2008)

Not yet started

[15]

In addition to the archives at the Eugenio Battisti Museum, GSES and CONASES are promoting other acquisitions and preservation of documents at other organizations and institutions. For example, at the University of Bologna, the inventory of the archive of Giacomo Ciamician (1857 — 1922), known as the father of photochemistry, will soon be completed. The 150th anniversary of his birth was celebrated in Bologna in 2007 [16] [17]. Ciamician’s famous paper on “The photochemistry of the future,” presented in New York in 1912, is available in English, French, and Italian at www. gses. it.

The collected archives contain notes, letters, articles, patents, the proceedings of Italian and international conferences, journals, clarification notes exchanged with academics, companies and research centres. They also include photographic documentation on experiments and prototypes, and some personal documents that give us a better idea of each personality. Most of the documents are in Italian, but there are also many letters and documents in other languages, including English, French, and German.

These and other archives, as well as information preserved at public and private libraries, can be important for both the history of solar energy and for rediscovering overlooked concepts and solutions, concepts that can now be improved thanks to newly acquired scientific and technological knowledge [18]. The intention of the GSES and CONASES project is to make most of the archives easily accessible via Internet. Current cooperation among the Museo Eugenio Battisti, the Central State Archive, the State Archives Department, and other institutions and organizations should allow a first structure of the Archive to be on line by 2011.