"The recession caused by the banking crisis came on top of a difficult time for the PV industry in Europe
In the 1970s, the Department of Energy (DOE) set the goal of production cost for Photovoltaic (PV) wattage at $0.5. Why do you think this goal has not been reached to date?
Most of the world’s PV production is still based on bulk silicon cells, the key element in determining the cost of the finished cell is the raw material. Other factors are contributing more to the cost than in past years but still the raw material is the major factor. Consequently, fluctuations in the price and availability of silicon wafers still have a large bearing on the industry. Thin film manufacturers do not entirely escape the fluctuations in the cost of silicon wafers. When wafers are plentiful it becomes more difficult for thin film to offer a lower cost alternative and interest in thin film technologies wanes. The USA has invested heavily in thin film technology which looks the most obvious path to lowering the cost per watt due to the comparatively low material cost of thin film panels. However the subject is complex. The higher efficiencies available from bulk silicon modules, current low cost of raw material, the push for thinner cells utilizing less bulk material and the comparatively low cost of entry to becoming a manufacturer all influence the PV road map.
The 1970s goal of $0.5 / watt production cost was a target to achieve grid parity during a period of relatively high oil prices. We still do not have grid parity today but the industry is getting much closer to competing with fossil fuel generated power.
Climate policies announced by China and the United States cite a common goal of a 17% emissions reduction, which is equal to slightly more than a 40% reduction in emissions intensity by 2020. Energy from renewable sources, including solar PV energy, is expected to play a key role in reaching this target. Is this figure achievable by 2020 and if so, why?
Reduction of emissions of Greenhouse Gases is a global goal which will require a global effort. For rapidly expanding economies like China and India the challenge is greater. Much remains to be achieved but with a global political will much can be achieved. The target of 40% reduction of emissions intensity in the next ten years is a challenging goal but I think it is necessary to set high expectations if we are to achieve any real progress in this area.
The majority of PV generating capacity installed today is based on silicon solar cells. Can you tell us why thin-film solar panels on glass or flexible foils are gaining market popularity?
Thin film panels typically provide lower output for the same real estate. Where real estate is not an issue, for instance some solar farms. Where the panel has an additional function to generating power, for instance in building integrated PV, thin film panels can be a good alternative to bulk silicon. I think we need to see thin and crystal silicon as two separate markets with different applications. There are areas where the technologies cross over but generally the application chooses the technology.
Solar cell manufacturing requires several thermal processing steps. Can you briefly explain each step?
The first thermal step is Diffusion. Phosphoric acid or sometimes Boron (depending on the required junction) is diffused into the surface of the wafer. The second thermal step is a thermal deposition of Anti reflective Coating typically silicon nitride but other materials can be used to improve the refractive index of the wafer.
The field and grid patterns are printed on the surfaces of the wafer and after each print the wafer passes through a thermal drying cycle. Once all the layers are printed the wafer will be fired using a high speed firing process through a short wave infra-red furnace. Significant efficiency gains can be achieved by optimizing the firing process. The BTU Tritan tri speed belt furnace is particularly effective in improving finished cell efficiency through optimum firing.
According to recent IMS Research, the Americas’ and Asia’s PV market share is forecast to climb over the next five years and these regions will become “major drivers” in the industry. Can Europe compare to these regions and if so, in what capacity?
There is a great deal of work being carried out in Europe on the development of high efficiency solar cells for the terrestrial market. As these technologies are commercialised they may well be adopted by manufacturers in Asia but this will only drive the industry to greater efforts to improve efficiency. The end- user will be the winner of this Technology Race. Currently Europe is the main consumer of PV products. If Europe’s role as a supplier to the market diminishes significantly European governments may be less inclined to support the industry through taxpayer’s money so reaching grid parity becomes even more important.
What effect has the global recession had on the PV market in Europe?
The recession caused by the banking crisis came on top of a difficult time for the PV industry in Europe. The government incentives for PV investment in Spain were a major stimulus to the industry, when they effectively disappeared, 40% of the world demand for PV disappeared. The recession has increased the opportunities for Chinese competition to European manufacturers. Money for investment is scarce in Europe while in the same period, investment in this industry in China has been unprecedented. On the positive side, low cost PV products from China in particular have opened the market up, creating demand where it did not exist before.
What advantages does BTU have over its competitors?
BTU has over fifty years of experience in the manufacture of thermal processing equipment. Our manufacturing capability in both China and the USA allows us to be cost effective while serving a global industry. Development and customer demonstration facilities in China and USA means that we keep in touch with process developments in all of our markets. Our success in both the crystal silicon and thin film markets provide us with a broad product range which encompasses the key requirements of the PV industry. BTU has a global support structure serving a worldwide customer base, which ensures that we are truly international in all of our markets. Additionally the TRITAN firing furnace is a unique product in the market which allows cell efficiency to be enhanced during the metalization process.
While grid parity garners most of the attention, the breakthrough of residential solar and mini-grid systems in the developing world may prove a more transformative event for the future of PV. What role can BTU play in this?
The PV industry is changing rapidly. China, Taiwan, Korea and India have grown to become major manufacturers of both cells and modules, taking the place of some European manufacturers. Many traditional European manufacturers now have production facilities in Asia. These new manufacturing regions will become major consumers of PV. China and India are already investing in huge solar farms but rural areas in particular will benefit greatly from small, non-grid related installations. BTU has been a major supplier to the PV industries in China and India for many years. Korea is becoming a key market for us; we are supporting markets in many of the countries which are pioneering mini-grid and non-grid residential installations.
What changes do you think 2011 will bring to the PV industry?
There is real growth potential for the PV industry in 2011. A potential to begin to return to the meteoric growth rates seen a few years ago. New markets are appearing in Europe as countries which have not provided PV installation incentives in the past now introduce Feed in Tariffs. India and China will become more important as consumers of PV. China in particular will continue to grow its market share as a supplier of cells and modules. In crystal silicon High Efficiency Cells will become more of a focus. I think that manufacturers with an interest in both crystal silicon and thin film will probably be more focused on crystal silicon in the short term.
What can we expect from BTU Europe in the coming year?
2010 saw our sales in PV related equipment outstrip our Electronics Assembly Business for the first time. BTU will build on this success in 2011, developing new partnerships and working closely with our customers to deliver what they need to be successful. Our product portfolio is strong; we will expand and develop these products in the coming year.