No solar technology can claim to offer what concentrated photovoltaics (CPV) does, be it the superlative efficiencies in high-DNI regions, or zero-water usage in passively cooled systems.
Just like concentrated solar power, CPV works best in regions with high Direct Normal Irradiance (DNI), especially with values above 2,000 kWh/m2. And just like standard flat-plate photovoltaics, CPV has the benefit of modularity, thus can be designed to meet any electrical requirement.
“CPV is the most appropriate technology offering for the MENA region due in part to very high efficiency and excellent performance at high temperatures, ease of installation, and high potential for local manufacturing,” says Vahan Garboushian, CEO at Arzon Solar, and former CEO of Amonix.
Improvements, cost reductions
Europe’s largest solar research institute, Fraunhofer ISE, recently demonstrated a CPV module efficiency of 36.7% at Concentrator Standard Test Conditions, and many commercially available CPV modules exceed 30% efficiency.
As for cell efficiencies, the U.S. National Renewable Energy Laboratory has just developed a four-junction III-V multi-junction solar cell with a conversion efficiency of 45.7% at 234 suns concentration. The cell can use up to 700 suns concentration and still achieve an efficiency of 45.2%.
Prices are also decreasing. A typical 10 MW CPV project in 2013 cost between €1400/kW and €2200/kW. Based on these system prices, Fraunhofer ISE estimates the levelized cost of electricity for CPV power plants to range from €0.10/kWh to €0.15/kWh in DNI of 2,000 kWh/m2/year.
“The total capital equipment requirement, while varying by design and manufacturing process, can be lower for CPV than for traditional flat-plate technologies, including crystalline silicon”, states Fraunhofer ISE in a newly published report on the status of CPV.
A preference for HCPV
Despite the efficiency improvements and overall advantages of CPV, which would be best harnessed in the sun-rich countries of the Middle East and North Africa (MENA), the technology has been limited to a few, small-scale projects, mainly in Saudi Arabia, where the world’s first CPV installation was built in the early eighties.
Saudi Arabia in fact is the only Arab country to have embraced CPV. Out of 48 CPV power plants worldwide that have a capacity of 1 MW or more, two are located in the Kingdom. While Soitec’s 1.1 MW CPV demonstration system in Tabouk uses Fresnel lenses, Solar Systems’s 1 MW system at the Nofa Equestrian Resort uses reflective optics. Both power plants use high concentration CPV (HCPV) and have been operating since 2014.
According to Fraunhofer ISE, more than 90% of the capacity installed through end November 2014 is in the form of HCPV with two-axis tracking. The reason for that, the report states, is the significant increase in the efficiency of individual modules, which also leads to a reduction of area-related costs.
So why are most of the region’s solar projects employing PV? Abengoa, for example, has been contracted to develop a 15 MW solar array using polycrystalline cells for Saudi Arabia’s Al Khafji desalination plant, and in Dubai’s Sheikh Mohammed bin Rashid Al Maktoum Solar Park, PV has been the technology of focus has so far.
“The MENA region has typically been slower to adopt perceived new technologies by letting others test and prove out first. With over 200 MW global installations, CPV is at the point where it can pass from the early-adopter stage to that of being embraced by large companies with the wherewithal to incorporate CPV into larger scale opportunities across multiple platforms,” explains Garboushian.
“Issues regarding bankability have challenged CPV providers to acquire financing for developing projects,” he notes, adding that these issues are slowly being eliminated through CPV manufacture attrition and financiers having the opportunity to see “real-world” project performance data.
According to Oscar de la Rubia, director of operations at ISFOC (Institute for Concentration Photovoltaics Systems), the biggest barrier for CPV at present is that the prices of silicon PV are decreasing and that the CPV market is not large enough for economies of scale.
“There are international codes for CPV that ensure the reliability of CPV modules and tracking systems. If manufacturers are able to comply and certify their products according to these standards, the reliability of CPV in MENA region can be ensured,” De la Rubia stresses.
However, the lack of large CPV installations in desert areas and the limited track record of successful projects represents a persisting challenge, given that CPV only entered the market in the mid-2000s.
“We have been involved with independent due diligences of CPV projects in Spain and Portugal for the financing entities, and I think the same barriers are applicable to MENA countries,” says Carlos Suarez, senior project director at Altermia, an independent, Spain-based technical consultancy specializing in renewable energies.
He cites the competition between small CPV manufacturers and large crystalline and thin film manufacturers, and the CAPEX-OPEX-efficiency of CPV technology, which has not been able to beat crystalline and thin film projects.
“The challenge of CPV technology in the MENA region is to demonstrate, with the available data of the rest of world plants under operation, that CPV is feasible; that they can be competitive against other technologies; and that they have the capacity to manufacture CPV technology in MENA countries,” explains Suarez.
“This is something that crystalline and thin film manufacturers have done in advance and that’s the reason they took the leading position.” So intense was the competition that it squeezed out many CPV players out of the market.
Others have been close to the edge, such as Soitec, which announced it would be implementing a strategic plan that aims to re-focus the company’s activities on its core electronics business. How this decision will affect the French company’s activities in Saudi Arabia remains unclear.
Soitec had signed an MoU with Saudi investment group Khaled Juffali in 2013 to cooperate on solar energy development in the region, and its CPV demonstration system at Medina College of Technology in Saudi Arabia continues to serve as a platform for applied solar energy research and training. Soitec’s CPV business, however, could be revived following San Diego County’s approval this month for the company to move forward with two major new power plants.
Enhanced product offering
Overall, the CPV manufacturers that have survived are actively working on improving their products and expanding their focus. A good example is Australia’s Solar Systems.
The company is currently developing the next generation of their product, which will operate at a much higher efficiency and can be used for cogeneration of electricity and thermal energy.
“We are now working on cogeneration applications including desalination and absorption chilling,” says Chris Murray, CEO of Solar Systems, whose portfolio includes six operational CPV plants in Australia and one in Saudi Arabia, all generating electricity.
“We can supply water between 70 and 100 degrees Celsisus, which can be used to provide energy to applications such as desalination, agricultural uses, such as heating of green houses and livestock housing, or for absorption chilling. This has great application in hot regions where the absorption chilling can be utilised for centralised air conditioning systems.”
The latest interest in CPV has been shown by Taqnia, the technological investment arm of the Saudi government. After acquiring American CPV manufacturer Solar Junction, the government entity invited proposals last summer for the EPC of 6 MW of CPV projects.
The power plants will exclusively use Solar Junction’s triple junction cells and will comprise a 5 MW plant in Tai’f city and a 1 MW CPV plant near the Solar Village. Taqnia has already made it clear it intends to develop, construct, and operate CPV solar plants in the Kingdom, to determine which CPV systems can achieve best project economics with Solar Junction cells.
It doesn’t come as a surprise that MENA countries remains a central focus for CPV manufacturers, including Arzon Solar, which are actively marketing their new product offering to developers in the region and investigating local partnering opportunities.
“We have several outstanding proposals that have been submitted and are awaiting award notification,” notes Garboushian. The company is focusing not only on utility scale projects but also on smaller systems, including commercial/industrial and ground mount applications.
Solar Systems is also eyeing markets that have high DNI and the regulatory framework that can support solar energy, particularly in the Middle East, where it has been in talks with potential investors. “We’ve seen significant interest and are working with a number of parties towards an investment in the business by the middle of 2015,” says Murray.
At the same time, CPV demonstration projects are underway, which, like Soitec’s system in Medina, will prove the potential of the technology in the region’s environment.
“ISFOC is managing a project in Abu Dhabi, for Masdar, where there are several CPV technologies and the grid connection should be ready in the next months,” reveals Oscar de la Rubia. “The results of this project and the demo installations done by CPV manufacturers could show the good performance of this technology.”