According to Dr. Milan Rosina, Yole Developpement, high concentration PV (HCPV) does not follow the same way as PV. Adapted applications and installations in suitable regions are necessary. There are synergies between HCPV, LED, automotive and PV industries. New market entrants could help in the business development Dr. Rosina was speaking at an HCPV seminar organized by Yole.
He added that more than 80 companies are currently working in developing HCPV technology. Over 30 firms are developing new modules and systems. Large-scale installations are underway. There is said to be a large potential for the LCOE cost decrease. Positive track record from the large-scale installation could significantly improve the bankability of HCPV systems. However, strong competition with flat-module PV will remain.
Earlier, touching upon solar electricity generation and HCPV at a glance, he said that cells based on III-V materials have currently the best efficiencies, both in laboratory and in industrial production. A world record efficiency of 43.5 percent under concentrated light was obtained in 2011 by Solar Junction of USA. Commercially available cells are produced by Spectrolab of USA, Emcore of USA and Azur Space of Germany that reach 39-40 percent efficiency.
III-V cells have been used since 1997 to power satellites in space. They are too expensive to be used in standard terrestrial applications. Therefore, these are combined in terrestrial applications with light concentration systems in order to increase the efficiency and to decrease the cost per watt. The interest of HCPV is to use only a small amount of III-V material and to concentrate the light onto very efficient cells.
Drivers and barriers
Marker drivers and advantages of HCPV include high power production (MWh/y per watt installed) in high DNI areas due to high system efficiency, sun tracking, amd low temperature coefficient. There is reduced consumption of (costly) semiconductor material due to the use of optical concentrating system. Other advantages include system modularity, ,inimal water use, low environmental impact, promising LCOE potential in the high DNI areas, and large potential for efficiency increase and cost reduction.
As for market barriers, HCPV is still a niche market. There are geographical limitations for installations (high DNI required). It is best adapted for ground-mounted power plants only. There is high system price to contend with, as well as low product maturity and lack of standards and independent track records. Finally, there is competition with all electricity sources, especially with CSP and PV.
HCPV systems are targeting the utility market, e.g. electricity production on a large scale. An HCPV system is a multicomponent and multidisciplinary system.
System components include solar cell, receiver module, concentrating optics and HCPV module. High-precision assembly of all elements into the module is the key factor for reaching full module and system performance. The tracking system is equally important.
Before the end of 2010, there were over 50 HCPV installations. Most installations were in 10-kW or 100-kW range only. The biggest HCPV installation before 2011 used HCPV modules with high efficiency crystalline silicon solar cells (Amonix/Guascor Foton). The cumulative volume of all installed HCPV systems based on III-V cells was around 15MW at the end of 2010, e.g. less than 0.05 percent of the PV total installed volume (~40GW). These were mostly test and prototype installations, and therefore, received some additional funding that enabled these projects.
The market is likely to take off during 2011-2018. According to Yole, in 2011 the new installed HCPV capacity will be approx. 38 MW. The HCPV market will continue to grow and the annual installed capacity will reach 1,020 MW in 2018.
There has been a move to use larger 6-inch substrates in order to decrease the cell costs. This transition will be done progressively depending on the HCPV market size and the manufacturing complexity of the cells with new designs.
Forecast of market share increase for 6” wafers in the HCPV industry.Source: Yole Développement, 2011.
Some novel cell designs are no more using Ge as active substrate element. The new cell manufacturing techniques enable the use of more expensive substrates. Progressive market share transition to GaAs substrate. The overall market concerning HCPV epiwafers will surpass $175 million in 2018.
Reducing LCOE for HCPV
A reduction of more than 50 percent of the LCOE can be expected in the next five to 10 years (depending on the market development). There are different paths to decrease the cost of LCOE in HCPV.
These include: targeting installation sites with very high DNI; improving module efficiency, especially by an increase of cell efficiency; increasing the product maturity; going to mass production; going to high-volume installation projects; iImproving the manufacturing technologies; standardization/independent field test studies; and co-operation within the supply chain.
HCPV supply chain
The HCPV supply chain is currently moving toward vertical integration. There are three possible scenarios. First, a single player - present in one technological segment only. Second, a player within the partnership network with select players. Third, a fully integrated player - this is high added value, but a risky approach.
As of now, about 80+ firms are in the HCPV supply chain, and 30+ companies are developing new modules and systems. There are few leaders -- Amonix, Soitec and SolFocus have managed to enter the solar farms business.
Many other companies, namely optoelectronic companies with strong background in LED industry (epiwafer growth, thermal management system manufacturing, are seeking new business opportunities by diversifying their activities. Expected fast HCPV market growth will provide a significant increase on III-V epiwafer demand providing new business opportunities.
In 2011, the HCPV market size is too small to allow successful vertical integrations. There is a clear trend to vertical integration in order to propose complete HCPV solutions, to reduce manufacturing costs and increase system performance, reliability and durability.