 |
 |
||||||||||||||||||||||||||||||||||||||||||||||||
 |
|||||||||||||||||||||||||||||||||||||||||||||||||
|
|||||||||||||||||||||||||||||||||||||||||||||||||
 |
 |
|
|
| |
| photovoltaic: an opportunity? | |
| |
| |
| |
|
The market for photovoltaic devices (PV) — solar cells — has been growing rapidly over the past decade. In the past two years alone the market, in terms of mega watts production output, has nearly doubled. SolarBuzz recently announced that world production output reached 530 MWp in 2002, representing another impressive 36% growth over the previous year. According to figures produced by PV Energy Inc., in 2001 worldwide production of photovoltaic cells and modules, for both commercial and commercial applications, grew by 36% to a total of 390.54 MWp. World production has been steadily increasing in the Far East over the past five years with Japan leading production with 171 MWp (43%) in 2001, US with 100 MWp closely followed by Europe with 86 MWp.
World photovoltaic production Strategies Unlimited (SU) forecasts market growth over the next seven years at between 15% and 25% CARG. Production output in 2000, according to SU, was 235 MWp, with thin-film devices representing more than 10% of total PV production. Amorphous silicon accounted for 25 MWp in 2000 and 33.68 MWp in 2001. Assuming growth of the market at 25% by 2010 thin-film based PV devices would reach 233 MWp. Market data from PV Energy Inc. indicates that the average cost of crystalline silicon PV units is $3.50 — $4.00 per Watt. For amorphous silicon costs can be as low as $2.00 and as high as $3.00 per Watt. These figures, for silicon based PV cells and modules, set the total market at between $1,193 million and $1,387 million in 2001. Amorphous silicon based PV devices have efficiencies between 5% and 7%. In comparison, efficiencies for crystalline silicon are within the range 11% to 15%. For amorphous silicon to be competitive with crystalline silicon, and achieve adoption in the mainstream commercial market, its performance would have to improve to deliver efficiencies of greater than 10%. In terms of operational lifetimes it would need to achieve an operational lifetime of greater than 20 years. Despite having lower efficiencies thin-film PV devices are well suited to consumer applications. As performance improves they are likely to achieve greater penetration in a wider range of consumer applications. Figures published by NREL in 1999 indicate that manufacturing costs of thin-film devices where approximately $200 per m2 at an efficiency of 6% providing a cost of approximately $3.5 per Watt. These are broadly in agreement with published market data on commercial production average costs. The US Department of Energy has set long-term performance targets for thin-film based PV devices. These are efficiencies of 15%, at the module level, and $50 per m2 direct manufacturing costs. The eventual target is to achieve a cost of $0.50 per Watt. Organic semiconductor based PV cells can achieve approximately 2%-4% efficiency. These figures are for single layer devices. Research is currently being conducted that is exploring the practicality of multi-layer devices. By tuning each semiconducting layer to a specific band-gap it is possible to capture more solar energy per unit area. This technique is also being investigated for used in other thin-film PV technologies. What is even more interesting is that these PV cells use essentially the same device architectures as OLED based displays. Many of the manufacturing processes, materials, encapsulation and deposition systems used in the production of displays will be suitable for the production of PV cells. Consequently, the manufacturing cost models for displays will be a good first approximation for PV cells. Recently developed cost models (see OSA Vol 1. No. 5) for passive matrix OLED displays on a flexible substrate produce a cost per Sqft of $34.00 or approximately $340 per m2. Production capacity used for the model is 100,000 Sqft per week or 10,000 m2 per week. If the efficiency of the PV cells equals 6% this would equate to about $5.60 per Watt. In terms of power output this model produces 30 MWp per annum at a production cost of approximately $168 million. Given these figures, further research and the benefits of economies of scale from the display industry and it might be possible to imagine organic semiconductor PV devices being produced at costs comparable to amorphous silicon. If integrated with other organic semiconductor components a whole range of novel consumer devices may be envisaged. Questions to consider:
|
|
|
|
|
|
| copyright © cintelliq ltd 2003-2005 | |
