With a tough economic market and global differences in government subsidies, it has never been more important for European PV makers to focus on their production techniques to make solar even more profitable.
Over the past 20 years, the European solar industry has worked hard to gain global leadership. Today, there are over 130 European solar manufacturers, and 5.2 percent of the peak electricity demand in the 28 countries of the European Union is supplied by photovoltaic systems.
REC modules deliver a consistent output in the largest PV rooftop installation within the Basque Country in Spain. Courtesy of REC Solar Germany GmbH.
But in the past two years, European photovoltaics manufacturers have sustained some massive casualties, with around 200 manufacturers leaving the market. In addition, many downstream companies (distributors, installers and so on) closed their businesses or focused on other products instead.
Some experts place the blame on a combination of oversupply and illegal price dumping of solar panels by solar manufacturers in China.
“It is a destructive structure of the European market, triggered by China with its violation of the international trade law by massive subsidizing and illegal price dumping as it is examined by the European Commission,” said Milan Nitzschke, president of EU ProSun, a joint initiative of EU solar businesses that aims to promote sustainable energy production using solar technology. “Market-based companies have no chance against such tactics, even though European producers are leading in the future technology of photovoltaics.”
Global politics impacts solar success
Over the past several years, European governments have trimmed subsidies to solar power, prompting many private investors to withdraw from the industry and driven some companies to bankruptcy.
In Asia, on the other hand, business is booming as governments are today lending support that European manufacturers enjoyed from their own governments in the mid-2000s.
Massive subsidization by the Chinese government enables Chinese manufacturers to sell their products at widespread dumping prices far below their own production costs, according to Nitzschke.
“The surge of dumped solar panels which was imported to Europe since the last three years led to a [dramatic] price decrease, resulting in numerous closures of European companies and factories, as well as thousands of job losses,” he said. “Thus, Chinese companies took over about 80 percent of the entire European market.”
REC manufactures wafers, cells and solar panels for the solar industry; its headquarters are in Singapore. Courtesy of REC Solar Germany GmbH.
But Kit Temple, CEO of solar industry website ENF Solar of Surrey, England, highlights the similarities between the situation in China today and European businesses many years ago. For example, there are hundreds of smaller Chinese manufacturers with no government support selling at similar prices. “And with the big Chinese manufacturers, the support mostly took the form of favorable bank loans, which is similar to the support many industries receive from governments around the world.”
“Survival has been very difficult in the last couple of years, and many companies have gone bankrupt,” Temple said. “In China, over a hundred manufacturers decided to simply go into hibernation until the market improved. Most of those have now woken up due to improving market conditions in recent months.”
Some believe that the European market is also set to improve, thanks to recent European Commission regulations that effectively create an artificial level playing field by forcing Chinese companies to sell at a minimum price that is far higher than the prices they use to sell to non-European countries.
But import tariffs are not welcomed by all European industry experts; some believe that antidumping tariffs only serve to distort competition and harm the thousands of European companies that rely on low-priced solar modules. The Alliance for Affordable Solar Energy (AFASE) is a coalition of over 850 companies in the European PV industry that aims to prevent protectionism in the sector and promote the benefits of free trade for solar energy products.
Photonics has always played a vital role in improving many aspects of PV production, and in today’s economic landscape, advances in manufacturing techniques are, perhaps more than ever, crucial for businesses to succeed.
An employee at the REC production site controls the quality of REC wafers. Courtesy of REC Solar Germany GmbH.
“Photonics are relevant for the solar industry both from processing and materials point of views,” said Trond Westgaard, director of tech initiatives and strategy at Renewable Energy Corp., a manufacturer of wafers, cells and solar panels for the solar industry, with headquarters in Singapore. “Laser processing is today used for, e.g., patterned layer ablation processes.”
In terms of laser processing, the objectives are: on one side, to increase processing speed and reduce the cost of ownership of this type of equipment (long maintenance cycles and low costs of operation, including parts, are essential); on the other side, to improve processing results – for example, by uniform laser-beam-intensity profiles over relevant areas and by processes that avoid damage to the silicon layers.
There is also ongoing research on materials to enable manipulation of the solar spectrum. “Research institutes perform interesting research on materials for changing the solar spectrum (up-conversion and down-conversion of photons) so that it can be more effectively utilized in solar cells, but there still [appear] to be major hurdles for introducing this in commercial solar panels,” Westgaard said.
Two power plants of 1 MW each are connected to the local grid in Puglia, Italy. Courtesy of REC Solar Germany GmbH.
Nitzschke stresses the importance for the European market to return to a truly level playing field. “Then European manufacturers could again display their knowledge and high-tech production lines, turning the market from cheap imports to high-quality products,” he said.
Although many European manufacturers of solar cells and panels may have scaled back their production in recent years, European production equipment manufacturers are still world-leading. However, this position can be threatened if there are few European customers for the equipment manufacturers.
“Collaboration between European solar companies, with production inside or outside Europe, and equipment manufacturers is necessary for developing new technology,” Westgaard said. “This can then generate new technology – e.g., within production techniques – that will keep European companies competitive, but these collaborations need to be beneficial for both sides.”
1. Solar Generation 6, EPIA, Greenpeace International, www.epia.org/publications
2. AFASE (Alliance for Affordable Solar Energy): http://afase.org/en
Making solar cells
Different methods of solar cell production, as outlined by Solar Generation 6, EPIA, Greenpeace International,
1. Crystalline silicon technology
Crystalline silicon cells are made from thin slices (wafers) cut from a single crystal or a block of silicon. The main types of crystalline cells are: monocrystalline (mc-Si), polycrystalline or multicrystalline (pc-Si), or ribbon and sheet-defined film growth (ribbon/sheet c-Si).
A. Convert the 98 to 99 percent pure metallurgical silicon into high-purity polysilicon, known as solar-grade silicon (up to 99.9999 percent pure).
B. The polysilicon is melted in large quartz crucibles and then cooled to form a long solid block called an ingot.
C. A wire saw is used to slice the wafer from the ingot, which produces significant wastage – up to 40 percent of the silicon (known as kerf loss). Using a laser cutter reduces kerf loss; however, this can only be done on ingots formed by string ribbon or sheet/edge-defined film growth.
D. The top layer of the wafer is removed to make it perfectly flat. A potential difference between two points gives rise to an electromotive force that pushes electrons from one point to the other. A solar wafer needs to have a p-n between the surface and the bottom of the cell. This step takes place in a diffusion oven.
E. The deposition of an antireflection coating enables the cell to absorb the maximum amount of light. It also gives cells their typical blue color.
F. Metal contacts (usually silver) are added to the cell so the electrons can be transported to the external circuit. A thin metal grid, known as a finger, is attached to the front surface of the cell. Wider metal strips, known as bus bars, are connected to the front and back surfaces of the cell.
G. The cells are effectively sandwiched between layers of coating material to protect them from the environment and breakage. Transparent glass is used for the front, while a weatherproof backing (typically a thin polymer) is applied to the back of the module. Frames can be placed around the modules to increase their strength. For some specific applications, such as integration into a building, the back of the module is also made of glass to allow light through.
2. Thin-film modules are constructed by depositing extremely thin layers of photosensitive material onto a low-cost backing such as glass, stainless steel or plastic. Once the deposited material is attached to the backing, it is laser-cut into multiple thin cells. Thin-film modules are normally enclosed between two layers of glass and are frameless. If the photosensitive material has been deposited on a thin plastic film, the module is flexible, creating opportunities to integrate solar power generation into the fabric of a building or end-consumer applications.
3. Third-generation photovoltaics are beginning to emerge in the marketplace after more than 20 years of research and development. Many of the new technologies are very promising. One exciting development is organic PV cells, which include both fully organic PV solar cells and the hybrid dye-sensitized solar cells. These products have a significant competitive advantage in consumer applications because of the substrate flexibility and ability to perform in dim or variable lighting conditions. Possible application areas include low-power consumer electronics (such as mobile phone rechargers, lighting apps and self-powered displays), outdoor recreational apps and building-integrated PV.