A Guide to Industrial Revolution 4.0

In a city in southwest Germany, the products are running the assembly line. But don’t head for the hills just yet. What we are witnessing is the eagerly awaited birth of the Industrial Revolution 4.0 – conceived and delivered over the past seven years by a team of scientists at the German Research Center for Artificial Intelligence in Kaiserslautern (DFKI).
Yes, they have started the revolution without us! In this factory of the future, the manufacturing platform is no longer dedicated to standardized mass production.
Instead, a robotic production line responds to sets of customized specifications conveyed digitally by intelligent products-in-the-making. For example: “Fill with red liquid and affix label number two.” To put it simply, the goods manufactured at the research center in Kaiserslaurtern go into production carrying what can be described as their “product DNA.” They will be created, packaged, labeled, and shipped without much human intervention.
What’s more, according to Detlef Zühlke, chairman of Innovative Factory Systems at the center, that’s just one of the advances we can expect.
In a recent interview with pv magazine, Professor Zühlke described the work in which he and his colleagues are engaged as “a paradigm shift,” which originated in industrial research and development and is now being advanced by the German government “as very important for the future of our economy and, therefore, our nation.” While many have their own definitions of the coming revolution 4.0, Zühlke said, “For me, it involves the use of smart technology and smart objects. It includes embedded intelligence that enables all of the equipment and smart abstract objects to communicate with each other on a higher level than ever before.”

A paradigm shift

In very real terms, the factory of the future will make manufacturing more agile and competitive – providing the ability to react quickly to product needs and preferences in different markets. Soon, Zühlke expects to see more plug-and-play functionality on the assembly line, as well as higher levels of customization.
What’s more, retrofitting a legacy factory for the next revolution in manufacturing need not be exorbitant. “For example, in a bottling factory, very little will change,” he said. “Some new software and technology will be added, and employees must be trained at a more advanced level to monitor and operate more complex machines.” Zühlke remarked that he is already receiving suggestions from the manufacturing sector. “Someone asked me just the other day, ‘Why not use the iPhone to parameterize things [change production values] on the assembly line instead of buying special equipment?’ My reaction is that it’s worth considering: Increasingly, consumer technologies will move to the industrial market. These are cheap technologies, but they are very powerful.” Meanwhile, his work at the German Research Center for Artificial Intelligence is starting to gain momentum.
The German government will provide half the funding for a research consortium – a group of about one dozen companies – that will retrofit the first large-scale factory of the future.
“We are very excited,” said Professor Zühlke, “because Wittenstein [a manufacturer of intelligent mechatronic drive technology] has agreed to convert at least part of its factory in Stuttgart for the use of the group. We plan to start work immediately.”

Not so fast

While the embedded intelligence and sensor-driven technology used first in Kaiserslautern and now in Stuttgart will doubtless be adopted at some point by the evolving solar industry, other new production processes are already showing promise for immediate efficiencies and price reductions: According to Klaus Eberhardt, Technology Manager Photovoltaics at the M+W Group, an engineering firm based in Stuttgart, the solar industry will not be the first to adopt the factory of the future because costs must be kept down to ensure profitable margins.
“As of today,” Eberhardt told pv magazine, “most of the PV manufacturing facilities already are highly sophisticated. In order to implement the embedded technology needed for the factory of the future, mainly software is necessary – but no solar company wants to add a lot of fancy features. Every customer will be very cautious about any additional costs. Solar will not be the first one into the pool.”

Feedback technology

However, there is one area in which sensor-driven technology, in combination with advanced metrology, may be implemented sooner rather than later.
Ed Korczynski, Marketing Communications Director for Intermolecular – a Silicon Valley-based company that uses “high productivity combinatorial technology” to find new and better materials for the manufacturing of specific products – told pv magazine that “feed forward” technology could “tighten the distribution of parameters in the final devices coming off the line; with much snugger pinning and a much more standardized solar product.” Many manufacturers already use feedback technology – which is the opposite of feed forward.
In a feedback production line, after completing one manufacturing stage, metrology is used to compare the result with the specified target – and if there has been a deviation, to immediately adjust the prior stage so that the next device made will be closer to the specification.
In feed forward technology, if the measurement does not meet the specification, the next production step (rather than the prior one) will be adjusted to make a correction. For example, if the product were a fraction thicker than expected, the next step might be to etch off the extra material.
“In some cases,” explained Korczynski, “it may not be practical to tighten the process up-front any further. One of the few ways to reduce variability would be to add additional metrology and allow the second step in a sequence to compensate for the first step. This could be of value to the solar industry.”

Fab labs

Additive manufacturing or 3D printing also offers great potential for use in the industry. As opposed to traditional fabrication techniques, which are “subtractive” and rely on the removal of materials by cutting or drilling to form a component, 3D printing is an “additive” method that creates objects by putting down layer after layer of material.
Researchers in “fab labs” worldwide are already looking at how 3D printing can be used to combine successive layers of polysilicon in PV solar manufacturing.
Last year, the Massachusetts Institute of Technology (MIT) experimented with using ordinary untreated paper as the substrate on which the solar cells can be printed.
Also in 2011, engineers at Oregon State University for the first time successfully produced copper, indium, gallium and selenium (CIGS) thin film solar cells with inkjet printing – a process they believe will reduce raw material waste by 90% and will significantly lower the overall cost of producing solar energy cells.
“This is very promising and could be an important new technology to add to the solar energy field,” said Chih-hung Chang, an OSU professor in the School of Chemical, Biological and Environmental Engineering. “Until now, no one had been able to create working CIGS solar devices with inkjet technology.” And in another effort that is transcending the testbed to reach commercialization, Semprius, Inc., an innovator in high concentration photovoltaic (HCPV) solar modules, officially opened its first production facility on September 26 in Henderson, North Carolina. Developed with the support of the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), Semprius’ proprietary micro-transfer printing process makes it possible to produce the world’s smallest solar cell – approximately the size of a pencil point. Compared with conventional silicon-based modules, Semprius said its modules “are twice as efficient, and offer consistent energy output and superior energy yields while performing much better in hot climates.”

Rapid fabrication

All of these new ideas are being watched closely by Materialise NV in Leuven, Belgium, where researchers have been working on rapid fabrication for more than 20 years.
The company became the first Rapid Prototyping Service Bureau in the Benelux region in 1990. What was then known as Rapid Prototyping is now referred to as additive manufacturing or 3D printing, which Materialise NV defines as “a three-dimensional printing technique that starts from a 3D computer-aided design (CAD) drawing and results in a three-dimensional object manufactured in a wide range of plastics, stainless steel, titanium, and a growing range of other materials.” Toon Roels, the head of Materialise’s R&D and Engineering department, told pv magazine, “Additive manufacturing can contribute to the solar industry by increasing functionality, due to the fact that very complex shapes can be manufactured.” Roels brainstormed a list of the ways in which complex shapes might be needed in solar energy – among them:

• anywhere that liquids or gases need to be displaced (e.g., complex geometries are often needed to maximize cooling efficiency);
• complex shapes for the active elements that capture sunlight, consisting of various tiles or facets;
• trends in solar panels to make them free-form and have them printed on complex shapes;
• 3D printing of conductive materials, together with their matrix (which could involve 3D printing of the entire solar panel or printing of multiple materials); and
• progress could come from 3D printing of polymers, metals and ceramics.

Colleague Vanessa Palsenbarg, Corporate Communications Specialist for Materialise, added, “There is a reason why, after 20 years of existence, additive manufacturing is finally catching the attention of people, corporations and publications worldwide – because it has advanced to the point that it is ready to change the world. The software solutions that support additive manufacturing are efficient enough to transform how products are conceived, designed, and customized for the end-user. Moreover, the materials used to manufacture parts are durable enough to allow for components that are impossible to manufacture in any other way, to be put to use in end-use products and save on material usage and weight, without sacrificing quality or functionality.”

Ready to roll

Finally, roll-to-roll processing – also known as web processing, reel-to-reel processing, or R2R – has been popularized in the thin film sector of the solar industry. It involves creating electronic devices on a roll of flexible plastic or metal foil (in much the same way that a newspaper is printed). A crucial issue for a roll-to-roll thin film cell production system is the deposition rate of the microcrystalline layer.
In August of this year, Vantaa, Finland-based Beneq, a supplier of thin film coating equipment, joined with R2R-CIGS, a high profile photovoltaics project financed by the European Commission through its Seventh Framework Programme (FP7).
The primary goal of the ambitious initiative is to scale-up innovative laboratory processes to meet production requirements of flexible solar modules. In short, these processes need to be adapted to roll-to-roll production, while ensuring reliability, high throughput, and low cost.
Beneq CEO Sampo Ahonen says, “We see great potential in continuous production technologies, both in relation to the economy of production and the quality of the end product. This is why we are putting down a lot of time and effort in bringing our thin film coating technologies, both aerosol coating and atomic layer deposition (ALD), to the service of the industries we address.” R2R-CIGS, which began in April 2012 and will continue into 2015, intends to establish pilot lines for production of flexible solar panels.
The project is going to be of paramount importance in facilitating the wider application, as well as in cutting the costs, of solar photovoltaics. In addition to Beneq, the project consortium includes EMPA (Swiss Federal Laboratories for Materials Science and Technology), Flisom ZSW, Isovoltaic, SoLayTec, Mondragon Assembly, Manz CIGS Technology and CPI, and is coordinated by the Netherlands Organization for Applied Scientific Research (TNO).
What’s more, in September, the U.S. startup company SoloPower officially opened its new CIGS thin film photovoltaics manufacturing facility in Portland, Oregon – targeting 400 megawatts of annual capacity.
SoloPower employs a roll-to-roll electrodeposition process, which it claims is low cost and can produce high-efficiency modules. In a report issued on CIGS manufacturers, Lux Research wrote that SoloPower will have to produce “tangible results […] to stay in the race.”

It’s all about costs

According to Mark Bünger, Research Director at San Francisco-based Lux Research, the company may have a tough time keeping up with competitors. He told pv magazine, “Roll-to-roll production is not a batch process. Solar devices made that way are less efficient than conventional polycrystalline. In addition, costs have been high, so the advantage hasn’t been there. For large-scale production, thin film technology has had a hard time. By contrast, Tempe, Arizona-based First Solar, still the leading thin film manufacturer worldwide with the highest-efficiency product, uses a thin film cell sandwiched between two layers of glass.

Great expectations

At present, the solar industry is so new that there has been no consensus on the manufacturing method of choice – and many believe that it has yet to be discovered.
Indeed, Matthew Ayres, Managing Director of Growth and Innovation Asia Pacific – a Sydney, Australia-based consulting company focusing on top-line growth, innovation, and transformation – told pv magazine, “We are advancing to a global infrastructure in which intelligence moves from virtual to physical elements. Smart paint, smart surfaces, smart buildings, and smart power are just the beginning. Every surface will become a form of ‘power intelligence.’ Solar categories and production methods inevitably will progress over time. New models and formats within construction are likely to be the next major phase.”