Abengoa Solar

Abengoa Solar and Innovation 

For Abengoa Solar, innovation and the development of new technologies are key priorities. The company’s goal is to offer technologies that generate clean energy at a cost that can compete with fossil fuels.

The solar energy sector is a relatively young and highly technology-dependent industry. Innovation is therefore a key factor, enabling the emergence of better technologies capable of competing with fossil fuels on price (taking account of carbon dioxide emission costs). Two main drivers will combine to lower costs: increased market volume and more efficient new technologies. This is precisely where innovation has a vital role to play.

Abengoa Solar’s development of proprietary technology within its research and development department affords it a competitive edge. This fact is particularly significant given the company’s role at various different stages of the value chain: manufacturing technological components, operating as a plant developer and maintaining assets, inter alia.

Abengoa Solar’s unflinching commitment to research, development and innovation is thus characterized by:

• A global presence: The company employs a team of more than 100 people at research sites across the world - Seville and Madrid in Spain; Denver in Colorado, USA.
• Abengoa Solar cooperates with leading institutions, such as Ciemat in Spain; NREL, the University of Rochester and the University of California, Merced, in the United States; and DLR and Fraunhoufer ISE in Germany.
• Programs are funded by two distinct yet complementary sources. The company itself makes a major investment effort; in addition, it seeks public subsidies in Spain, the European Union and the United States. Major awards of public funds secured in 2010 under innovation support schemes included:
  • In Spain, the company continued the Cenit Consolida project into its third year, with a total budget of €24 M. Moreover, in photovoltaic technology the company is involved in the Cenit Sigmasoles and the Cenit Liquion projects.
  • In Spain, work has continued on three projects funded by the CDTI.
  • In the United States, Abengoa Solar has won a new research and development project awarded by the Department of Energy to develop a new solar power technology. Work is also continuing on four other contracts for the same department.

 

Abengoa Solar Innovation Highlights of 2010

In 2010, the R&D&I team continued to grow, further honing its capabilities in its core research areas and building pilot facilities to put new technologies to the test at a small scale but under real operating conditions.

Abengoa Solar operated several demonstration plants over the year to showcase its strategy in the field of new technologies. The company develops and tests its technologies at small-scale pilot plants with a view to subsequent application using large commercial facilities.

Abengoa Solar develops its technology research and innovation via the Stage-Gate methodology so as to achieve excellence in project development and management, and to bring its efforts into alignment with the organization’s strategic goals. Under this R&D&I management procedure, projects evolve by consecutive stages (Stages), subject to assessment milestones (Gates) at which the company assesses the extent to which it has achieved its objectives and overall project potential.

At the initial stage, the project to be undertaken is defined and preliminary research work completed. Next, the team conducts a thorough analysis and theoretical and practical modeling of the solution. This stage also includes searching for suppliers, signing cooperation agreements, and so on. At the next stage, a prototype or demonstration plant is built and brought into operation. The final stage consists of analyzing the pilot plant’s operational data in order to validate the demonstrated system with a view to undertaking large-scale commercial development.

Pilot plants help Abengoa Solar to face emerging technological challenges, which can currently be described as (i) raising the efficiency of converting solar energy into electricity, and (ii) bringing down costs. Specifically, pilot plants enable the company to test the following features:

• Higher operational temperatures. The key benefit is to increase the efficiency of solar energy conversion into electricity by enhancing the performance of the power cycle.
• New materials to withstand the high temperatures and steep temperature gradients involved in each operating cycle. Such materials are either insufficiently developed or would be too expensive for commercial use under present conditions.
• New thermal storage systems to facilitate energy supply management so as to deliver power to the grid over the desired periods. This is one of the key advantages of solar thermal technology - other renewable energy sources are not manageable in this way. A storage system raises the availability and capacity of the plant and makes for fewer turbine start-ups and shutdowns.
• Use of new heat-carrying fluids, such as water, for direct generation of steam, thus avoiding the need for expensive heat exchangers - which entail a loss of performance - or molten salts to achieve higher operating temperatures.
• Improvements in plant control and operation to enhance efficiency and reliability.
• Developing concentrating photovoltaic technology for competitive power generation at plants located in the sun belt.
• Integrating photovoltaic solutions with buildings and distributed generation centers.
• Power storage that brings photovoltaic generation into balance with electricity use, so improving the integration of photovoltaic power with the grid.

In response to these challenges, the company has continued to operate several pilot plants as part of the Solucar platform (Sanlucar la Mayor, Seville, Spain) over the course of 2010. The projects have validated a range of key innovative concepts:

• Operation of a tower plant at higher temperatures. Unlike the PS10 and PS20 models, the Eureka tower operates with superheated steam generated in a second receiver and reaching temperatures in excess of 500° C. The plant was commissioned in early 2009.
• In 2010, Abengoa moved forward with the engineering of new concepts for third-generation central receiver plants, with a view to starting to build pilot plants in 2011.
• Water certified as an alternative to oil in parabolic trough loops. The company’s direct steam generation plant, also commissioned early in 2009, is validating the control system developed by Abengoa Solar, thus meeting one of the main challenges of this technology.
• Validation of thermal storage. The operation of a molten salts demonstration plant in 2009 provided invaluable experience in the use of this fluid to store energy in the form of sensible heat and to quantify the overall performance of this storage mode.

.As with CSP technology, PV technology faces the challenge of developing systems that generate power at a cost that can compete with both other renewables and conventional sources.

Developing and operating certain efficient PV technologies represent an important goal for Abengoa Solar. In 2010, the company carried out the following projects:

• Development of a new high-concentration PV module that achieves very high efficiency at lower cost.
• Development of groundbreaking PV technology in terms of new materials at the Seville R&D center.
• Development of an experimental application to analyze the power generation cost associated with various technologies and configurations.

As a result of this R&D&I work, Abengoa Solar now owns patent-protected proprietary technology. The company owns rights to exploit a number of major inventions in the solar industry, making for 25 patent applications in 2010.

 

R&D Programs

The research and development program in the Solar’s business unit rests on four main pillars:

Central Receiver and Tower Technology

Abengoa Solar’s research focus on central receiver and tower technology is what sets it apart from its competitors.

One of the internationally recognized hallmarks of Abengoa Solar is to use tower and heliostat technologies in its quest for efficiency, particularly in the solar component of the plant.

In 2010, besides operating the Eureka plant for the production of superheated steam, the company undertook research and development relating to one of the main components of a solar plant: The receiver.

The Eureka project was intended to address new challenges in tower technology, now that the start-up of PS20 has amply confirmed its reliability. This second-generation solar tower achieves higher temperatures by producing superheated steam, thus enhancing the overall efficiency of the steam cycle. The plant consists of 35 heliostats and a 50 m tower mounting the experimental superheating receiver. The approximate power of the plant is 3 MWth.

In the field of tower technology, the company’s research and development was not confined to steam. Two new projects were initiated in 2009 to focus on two very different fluids: Molten salts and air.

The CRS Molten Salt project, co-financed by the Spanish CDTI, involves the engineering and manufacture of a tower solar receiver prototype in which the heat-carrying fluid is a mixture of molten salts. The purpose of the exercise is to appraise the technical and economic viability of a large-scale plant based on this technology.

In addition, the Solugas project (co-financed by the European Union’s Seventh Framework Program), got underway in 2008 and is intended to demonstrate the functioning of tower technology at higher temperatures, employing air as the heat-carrying fluid and a gas cycle instead of steam.

The engineering phase has been taken forward in both projects, with a view to starting construction of demonstration facilities in the near future.
In 2010, the company has developed a new heliostat that is set to reduce costs by almost 30 %. 

Parabolic Troughs 

Parabolic trough technology offers great potential for improvement in a wide range of its components, including its structure, mirror-fixing methods, tubing and interconnections. Abengoa Solar is researching all of these components. At its prototype facilities at the Solucar platform, it tries out many different configurations in an ongoing search for an optimum that secures the utmost efficiency at a competitive cost.

Since 2007, the company has operated an experimental loop comprising four collectors and using thermal oil as the heat-carrying fluid. Potential optical and thermal improvements have been assessed and all the key components of the technology have now been identified. This unique test bench has afforded the company a practical familiarity with the functioning of the plant, and the know-how acquired has been passed on to commercial plants now in the process of construction and operation.

2010 also saw continued operation of the direct steam generation plant. This plant comprises three loops and uses steam as the heat-carrying fluid. By removing the need for an oil-steam exchanger, the technology enhances overall plant efficiency. Yet this direct generation technology requires a far more critical degree of control than thermal oil; the coexistence of two phases of matter in the receiver tube makes for higher instability.

The company is also developing two new types of collector using different materials so as to sidestep commodity price risk.

The Cenit Consolida project is also continuing its research into improving components and transfer fluids. Here, the sought-after qualities are maximum durability and minimum environmental impact. 

Storage Technologies 

The technology underlying CSP plants is now reaching a state of maturity that positions solar power as a strong candidate to supersede conventional thermal plants. However, some major issues still have to be resolved, however. One difficulty is the seasonality of the energy source, meaning sunlight. This means that energy has to be stored in large accumulator systems;

Depending on the type of heat transfer fluid, oil or steam, the energy storage system will be designed accordingly to latent or sensible heat storage.

Steam stores heat in latent form, while oil stores it in sensible form. A hot body (e.g., a heat-carrying fluid) is brought into contact with a cooler liquid, solid or gaseous medium in which the heat is to be stored. As a result, the storage medium heats up. Using the sensible heat of the material, the medium stores energy as and when its temperature rises.

This technology has continued to be tested in 2010 at an experimental plant. The experience provided a highly valuable lesson in operation and optimization for the construction of forthcoming commercial solar plants with attached storage systems, such as the 280 MW Solana plant to be built in Phoenix, Arizona.

Where heat is exchanged with a fluid that, in that same process, undergoes a change of phase - becoming steam - the storage technology makes use of the energy associated with the change of phase of the material or mixture of materials. This technology is at a very early stage, but Abengoa Solar has already taken part in several research projects relating to storage with a change of phase. For example, the Distor project led to a prototype that underwent trials at the Almeria Solar Platform.

Abengoa Solar has also undertaken numerous projects to produce hydrogen using thermal and photovoltaic solar power, which can be used as an energy storage medium. 

Photovoltaic Technology

Concentrating Photovoltaics (CPV)

In partnership with NREL and several North American universities, the company is developing new concentrating photovoltaic concepts. Highlights include a new generation of Fresnel lens photovoltaic concentrators, a semi-static low-concentrating system and other innovative technologies. These concepts are expected to become, in the medium term, the drivers of new photovoltaic systems capable of generating power at a competitive cost.

The company has made a major effort to develop solar trackers for concentrating photovoltaic applications. It has successfully installed several CPV devices at a 400 kW plant at ISFOC (Instituto de Sistemas Fotovoltaicos de Concentración), Ciudad Real, Spain.

New Materials Technologies

Abengoa Solar is planning to build an R&D&I technology center in Seville province, Spain. The center will be the setting for applied research on new materials, photovoltaic cells, and thin-film photovoltaic prototypes and technologies. The knowledge thus generated will lead to proprietary and competitive technologies in support of Abengoa Solar’s future industrialization projects.

PV Laboratory

The PV laboratory built in 2008 has tested and measured the performance of a wide range of PV systems under real operating. Based on the data thus gathered, the laboratory has developed an experimental software application to analyze the cost of generating energy using different technologies and configurations.