Category: Spain

Abengoa Solar

Abengoa Solar

History of Abengoa Solar

Abengoa began its involvement in the development of solar technologies in 1984 with the construction of the Solar Almeria Platform in Spain. The company supplied heliostats and glass facets and worked on the construction of the Cesa Tower. Later, in 1987, Abengoa supplied the facets for the heliostat field of the Weizmann Institute in Israel.
This initial work was undertaken by the Abengoa company, Inabensa as part of its construction department.
In the 1990’s, a new department was created devoted to solar R&D projects. In 1983, Abengoa Solar IST (then Industrial Solar Technology) was founded by Ken May with the purpose of developing trough technology that was economically feasible for commercial and industrial applications.
The 90s: Concetrated Solar Power and Photovoltaic R&D Projects

In 1993, Abengoa built Toledo PV, a 1MW turn-key photovoltaic plant, that is owned by Union Fenosa, Endesa and RWE. The project was built with a subsidy from the European Union.
In 1994, several tower R&D projects were initiated. These projects were partially subsidized by the European Union under Framework Programs IV, V and V. R&D focused on different types of receivers. One of the projects, Solgas, focused on steam generation while the other, Colon Star, focused on electricity generation. Between 1995 and 2000, several R&D projects involving troughs began under by the EU Framework Program s IV and V. The following are highlights of the late 90’s R&D projects.

* The Theseus Project: The Theseus Project studied the feasibility of a parabolic trough plant in Greece.

* Eurotrough: Abengoa Solar was one of the leaders in developing the Eurotrough. The purpose of this project was to develop a parabolic trough with improved optical efficiency, and better manufacturing and assembly processes compared to existing designs.

* DISS: A research project investigating the direct generation of steam in the trough receiver. The research goal was a major technical advance leading to a 30% increase in the efficiency of parabolic trough electricity generation.

In the 1990’s Abengoa Solar also collaborated on dish-Stirling projects involving the production of the Eurodish and Envirodish.

Abengoa Solar worked on concentrated photovoltaic projects. The outcome was the low-concentration dishes (Sevilla PV) now installed at the Sanlucar Solar Platform.

During this time, Abengoa Solar IST worked with some of the world’s best labs and institutions to improve and install solar trough systems for industrial and commercial applications.

2004 to Present: Transition from R&D to Commercial Plant Construction

Based on the economic and technical foundation provided by investments in R&D, Abengoa Solar has transitioned into a pioneer in the construction of commercial CSP and PV plants.

In 2007, Abengoa Solar inaugurated the world’s first commercial solar tower plant, the 11 MW, PS10, and the world’s largest low-concentration PV plant ( Sevilla PV, 1.2 MW). These two plants are part of the Sanlucar Platform, which when complete in 2013 will have a total capacity of 300 MW. Such output can supply the needs of 18,000 households in Seville, while eliminating 600,000 tons of CO2 per year. Besides the Sanlucar Platform, Abengoa Solar is building additional plants in Spain, the USA, Algeria and Morocco.

Abengoa Solar New Technologies (NT) is the R&D company of Abengoa Solar in Spain. Abengoa Solar NT collaborates with institutions such as NREL, Ciemat and Fraunhofer, as well as research universities to develop CSP and PV technology. In addition, Abengoa Solar NT performs internally-funded R&D to develop new proprietary knowledge aimed at improving performance and reducing the cost of solar technology.


Operating Principle

Photovoltaic (PV) cells use semiconductors to produce electricity. The cell absorbs solar radiation, which excites the electrons inside the cell. A semiconductor must have at least two electric fields. When an electron excited by solar energy leaves its electric field, it seeks to return to its original electric field. In order to do so, it must pass through an external circuit, producing electricity. This is referred to as the photovoltaic effect.

PV technology

The following are the primary components of PV technology.

  • Optics: Different optical elements, such as mirrors and Fresnel lenses, are used to concentrate solar radiation onto a point where a PV cell is located.
  • Photovoltaic Cell: The photovoltaic cell is the semiconductor used to produce the photovoltaic effect.
  • Inverter: Since the photovoltaic effect produces direct current (DC), an inverter must be used to change it to alternating current (AC).

Types of Photovoltaic Cells

There are two predominate PV systems on the market. Each has their own pros and cons regarding application, efficiency, and cost.

1 Crystallized Silicon (~200 µm)

A double layer antireflection coating is used to reduce reflection losses on the front surface of crystalline silicon wafers. The wafers are about 400 µm thick to ensure near-complete absorption of all photons having energy greater than the band gap. At the bottom of the wafer, a SiO2 layer is inserted between the wafer and the aluminum backing to achieve reflectance back toward the cell.

  • Single-Crystalline Si
    The semiconductors of most PV cells are made from single-crystalline Si. This requires highly purified silicon to be crystallized into ingots. The ingots are then sliced into thin wafers to make an individual PV cell.
  • Polycrystalline Si
    Polycrystalline Si cells are produced in a way very similar to single-crystalline cells. The primary difference is that silicon of less purity is used for polycrystalline cells. The result is reduced cost and increased ease of production, but a loss of efficiency.
  • Ribbon Si
    Ribbon type PV cells are produced in a similar fashion to single- and polycrystalline silicon cells. The primary difference is that a ribbon is grown from molten silicon instead of an ingot. These cells often have a prismatic rainbow appearance due to their antireflective coating.

Ribbon Si

Thin film (~5 µm):

Thin film semiconductor technology may not be as efficient as traditional semiconductor technology, but its light weight and low cost make it an ideal solution for certain applications.

Amorphous Si

  • Amorphous Si
    Unlike crystalline semiconductors which have a band gap of 1.1 eV, by manipulating the alloy of amorphous silicon semiconductors the band gap energy can be tuned between 1.1 eV and 1.75 eV. Additionally, because they have a much greater absorbance than crystalline silicon, amorphous silicon semiconductors can be much thinner (less than 1 µm). Although amorphous Si cells can be manufactured at low temperatures (200-500 C) and at low costs, a major drawback is their light-induced degradation.

Amorphous Si

3 Copper Indium Gallium Diselenide Solar Cells

  • 3 Copper Indium Gallium Diselenide Solar Cells (CIS Cu In Se2)(CIGS Cu(InGa)Se2)
    Due to its relatively high efficiency and low material cost, this technology has emerged as one of the most promising thin films. By adjusting the ratio of In to Ga in CIGS cells, the band gap can be tuned between 1.02 eV and 1.68 eV. The absorption elements of CIGS cells are incredibly high, allowing more than 99% of incoming radiation to be absorbed within the first µm of material. Although this technology has a relatively low material cost, the complicated and capital-intensive manufacturing methods remain as significant drawbacks.

CIGS Solar Cell

Cadmium Telluride

  • Cadmium Telluride (TeCd)
    Cadmium Telluride is another thin film technology that has been available longer and undergone more research than any other thin film technology.
    Although there are diverse manufacturing techniques that can be used to produce the films, many of which are promising for large scale production, the cost and potential health concerns remain as drawbacks for this technology.

Cadmium Telluride

  • Micro Si
    Micro silicon cells are expected to surpass the efficiency and performance of amorphous silicon cells and become a competitor with other thin film technologies. The high efficiency and negligible degradation of Micro Si cells has been widely reported.
  • Titanium dioxide (TiO2)
    Instead of the semiconducting materials used in most cells, TiD cells use a dye-impregnated layer of titanium dioxide to generate voltage. Because of their relatively low cost, TiO technology has the potential to significantly reduce the cost of solar cells.
Photovoltaic Concentration

Offers the best efficiency but requires high direct concentration, and is therefore only viable in some geographies.

Fresnel point focus

  • Fresnel point focus (High concentration-GaAs) (GC~500)
    Fresnel point lenses concentrate direct solar radiation onto a focal point. Since Fresnel lens can provide concentration ratios of up to 500, the necessary surface area for PV cells is greatly reduced. Since fewer PV cells are needed, it is possible to use high quality, more expensive materials like Gallium Arsenide for the semiconductors.
    Gallium Arsenide (GaAs) multi-junction semiconductors: Multi-junction semiconductors is a relatively new technology that offers significantly higher efficiencies than traditional, single-junction semiconductors. Each electrical field junction within a semiconductor has only one band gap energy. Incoming solar radiation will either have less energy than the band gap (and therefore will not be used), more energy than the band gap (and therefore some energy will be wasted), or the exact energy as the band gap. By having multiple junctions, GaAs semiconductors are able to utilize more energy from the incoming solar radiation.
  • Fresnel line focus (medium concentration-Si) (GC<500)
    Fresnel line lenses are flat cylindrical lenses that condense or diffuse light in a linear direction. This technology has lower concentration ratios than Fresnel point lenses, so high efficiency silicon semiconductors are used instead of expensive GaAs semiconductors.
  • Low concentration (2-4 times)
    Low concentration (2-4 times) Low concentration technology uses mirrors instead of lenses to concentrate solar radiation. Since the solar radiation is much less condensed, conventional silicon semiconductors are often used because of their affordability.

SolFocus Inc.

SolFocus Inc.



SolFocus, Inc.

510 Logue Avenue
Mountain View, CA 94043
Phone: +1.650.623.7100
Fax: +1.650.623.7101


SolFocus Europe, Inc.

María de Molina 39 7° Izq.
28006 Madrid, Spain
Phone: +

SolFocus has developed leading concentrator photovoltaic (CPV) technology which combines high-efficiency solar cells (approaching 40%) and advanced optics to provide solar energy solutions which are scalable, dependable and capable of delivering on the promise of clean, low-cost, renewable energy.

The SolFocus mission is to enable solar energy generation at a Levelized Cost of Energy (LCOE) competitive with traditional fossil fuel sources. To achieve this goal, SolFocus has developed leading concentrator photovoltaic (CPV) technology which combines high-efficiency solar cells (approaching 40%) and advanced optics to provide solar energy solutions which are scalable, dependable and capable of delivering on the promise of clean, low-cost, renewable energy. SolFocus is headquartered in Mountain View, California with European operations headquartered in Madrid, Spain, and manufacturing in Mesa, Arizona as well as with manufacturing partners in India and China.


SolFocus Technology Highlights

By concentrating sunlight using innovative optics onto a small area of high-efficiency solar cell material, SolFocus systems dramatically reduce the amount of expensive and often supply-constrained solar material used in the system. Learn more about SolFocus technology by selecting the components below.

Sol Focus CPV Sytems

CPV Power Unit

CPV Power Unit

Solfocus has developed an innovative reflective optic system which includes a primary mirror to capture sunlight and secondary mirror and non-imaging optic to concentrate it at 500 suns onto high-efficiency III-V solar cells.

CPV Power Unit

  • All-glass optics for durability
  • Low optical losses for high efficiency
  • Wide acceptance angle for high yield and lower cost
  • Designed to avoid chromatic aberrations and cell mismatching
  • High efficiency cells greater than 38% efficiency compared to 13% to 19% efficiency for silicon PV cells
  • 1cm2 cell per unit results in use of 1/1000th the active PV material
  • Robust cell design, originally designed for the demanding environment of satellites in space
  • High performance at high temperatures – not impacted by temperature degradation as are silicon PV cells

CPV Panel

CPV Panel

The CPV Power units are integrated into a robust panel design which is optimized for high efficiency, high reliability, and field durability. The panels are TUV certified and CEC listed.

CPV Panel

  • Industry-leading efficiency and power output
  • TUV certified, CEC listed
  • Power output rated at operational conditions
  • High energy output sustained at high temperatures
  • Utilize field-proven materials for high reliability and field durability
  • 95% glass and aluminum components for high recyclability
  • Glass components immune to long-term UV degradation
  • Panels fully enclosed with no exposed mirrors
  • Passive cooling system for high reliability and low cost

CPV System

CPV System

SolFocus CPV systems with their industry-leading efficiency can be deployed from small to large-scale installations, providing high energy output and maximum energy production per area of land.

CPV System

  • Maintains high energy output at high temperatures
  • Maximizes energy production per acre/hectare to reduce land use
  • Systems scalable from hundreds of kilowatts to 50+ megawatt installations
  • Allows dual-use of land
  • Robust, industrialized design for field durability and system reliability
  • High-volume manufacturing not impacted by silicon supply constraints

Dual-Axis Tracker

Dual-Axis Tracker

SolFocus CPV panels are integrated with dual axis trackers and precise tracker control systems which are optimized for the SolFocus panels, maintaining high energy output throughout the day.

Dual-Axis Tracker

  • SolFocus designed trackers are optimized for SolFocus panels and integrated into a complete system
  • Engineered for optimum stiffness and provide tracking accuracy of 0.1 degree
  • Extended tracking range for all locations
  • Ephemeris-based open-loop tracking
  • Self-calibration using proprietary SolFocus control system
  • Wind and night stow positions for safety and reliability
  • System monitoring software calibrates pointing accuracy
  • Remote system management reduces onsite maintenance

Acciona Energy

 Acciona Energy

In 19 countries

The Energy Division of ACCIONA has over 200 companies in 19 countries.

The corporate purpose of most of them is the development of wind parks and the production of electricity from them. Within the wind power sector the group also has manufacturing companies that produce wind turbines.

ACCIONA Energy also has companies that operate in the thermolectric field (biomass and solar thermoelectric), solar (photovoltaic and thermal), biofuels and others.


World leader in renewables

ACCIONA Energía is a world leader in the renewables sector. The company has taken on the mission of demonstrating the technical and economic viability of a new energy model on the basis of criteria of sustainability.

ACCIONA Energía is present in the main clean energies, in line with their different levels of maturity and profitability. It focuses its activities on wind power, in which it is the largest developer and constructor of windparks in the world.

It is also present in other electric power generation technologies based on renewable energy sources -biomass, small hydro and solar-, and also in the manufacture of wind turbines (designed in-house) and the production and marketing of biofuels. It also has assets in the field of cogeneration.

ACCIONA Energía is currently carrying out research projects to produce hydrogen from wind power, to manufacture more efficient wind turbines and to optimize the production of biofuels.

The company has a workforce of over 1,000 people, one of the biggest and most highly qualified in the clean energies field.

The solidity of a great group

ACCIONA Energía is the energy division of ACCIONA, a leading group in infrastructures and services aimed at sustainable development and social welfare.

ACCIONA is a homogeneous and integrated business group with a focus on operations with high added value that enable it to create synergies and make profitable investments in strategic sectors.


Wind energy

A global leader in wind energy

ACCIONA Energy focuses its activity on wind energy, a field in which it has so far installed 5,577 MW at 30 September 2008. It has built 200 windparks for itself and other companies with over 5,500 turbines, making it the world leader in the development and construction of windparks. At the same time, it has 900 MW under construction and around 15,000 MW in development.

The wind power installed by ACCIONA Energy in Spain amounts to 4,471 MW.

On all five continents

As well as Spain, there are windparks installed by ACCIONA in the United States, Canada, Germany, Australia, Italy, Greece, Hungary, France, India, Portugal, South Korea, Mexico and Morocco. Of these, 142 windparks (4,105 MW) are owned by the Group, with an attributable capacity of 3,285 MW. The 58 windparks built for other companies account for 1,472 MW.

ACCIONA is currently building windparks in most of the above mentioned countries.

Current projects are being carried out in the United Kingdom, Croacia, Poland and Slovenia.


In 2007, ACCIONA Energy produced a total of 7,494 GWh of wind energy, of which 6,316 GWh were produced in Spain and 1,178 GWh in other countries. Attributable wind energy generation reached 5,570 GWh.

In the first nine months of 2008, the wind energy production was 5,840 GWh (4,784 GWh in Spain and 1,056 GWh in other countries). The attributable wind energy generation was 4,620 GWh.

Mini hydro

19 small hydro plants in operation

ACCIONA Energy has 19 small hydro power plants located in different river basins in Navarre (Spain). Their total installed capacity is 58.79 MW.

In 2007 hydroelectric production from these plants reached 193 million kilowatt-hours. Until September 2008, the power output was 182 GWh.

ACCIONA also handles the operation and maintenance of another six hidroelectrical plants.


Three plants in operation and seven under development

ACCIONA Energy is present in the field of biomass with three plants that total 33 MW of installed capacity. They produced around 240 million kilowatt-hours (kWh) a year.

The largest is a 25 MW cereal straw-fired plant in Sangüesa (Navarre), a pioneering facility in southern Europe in the exploitation of this source of renewable energy. Its average annual output is around 200 million kWh.

In addition to the Sangüesa plant, ACCIONA Energy has biomass plants in Talosa (province of Soria) and Pinasa (Cuenca), each one with 4 MW capacity.

New projects

The company is giving a boost to the biomass business in Spain. It plans to install seven new plants in different Spanish regions, which will be entering into operation between 2010 and 2012. They total 110 MW of capacity, 306 million euros investment and an estimated annual output of 880 million kWh. These facilities will represent 175 direct and 515 indirect new jobs, mainly devoted to primary sector.

In the region of Castilla y León, it is developing three new plants summing 55 MW of installed capacity and represent an investment of 140 million euros. The three facilities -located in Almazán (Soria) -15 MW-, Briviesca (Burgos) -15 MW- and Valencia de don Juan (León) -25 MW- will be participated by the Regional Energy Board (EREN).

Altogether the three plants will produce around 440 million kWh a year, equivalent to the demand of 180,000 homes. They will also create 300 jobs and will avoid the emission of 423,000 tonnes of CO2.

The plants planned in Castilla-La Mancha are located in Mohorte (Cuenca) and Alcázar de San Juan (Ciudad Real), with a total investment of 86 M€.

ACCIONA also projects to install a 15 MW biomass plant in Miajadas (Cáceres) and a 10 MW one in Utiel (Valencia)

Solar energy

Leaders in solar energy

ACCIONA works with all three solar technologies – concentrating solar power (CSP), photovoltaic and solar hot water – amounting to a total owned capacity of 194 MW, of which 113 MW are owned by the company.

The company has so far installed 81.32 MW for other companies, of which 66.18 MW are photovoltaic, 14.14 MW are solar heating and 1 MW are CSP.

Technology Owned capacity Capacity for other companies Total capacity
CSP 64.00 1 65.00
Hot water 0.72 14.14 14.86

The largest concentrating solar power plant in 17 years

In June 2007, in the state of Nevada (USA), ACCIONA connected to the grid the the largest CSP facility of its type in the world in the last 17 years: the 64 MW Nevada Solar One plant. The company has a 97.7% stake in the facility, which is operational since June 2007.

ACCIONA has various CSP plants under development in Spain – all of which have a capacity of 50 MW – and is also involved in major projects in the south-western United States.

The leading developer of photovoltaic energy in Spain

The photovoltaic capacity installed by ACCIONA at 30 September 2008 amounts to 114.44 MW. Through its subsidiary ACCIONA Solar, the Group has developed the concept of “huertas solares” (solar gardens), a system that has allowed more than 3.500 people to become owners of photovoltaic installations.

The “huertas solares” installed by the company – 18 in total – amount to a capacity of 61,5 MW and are located in diferent Spanish regions.

ACCIONA is currently building what will be the biggest solar photovoltaic plant in the world in Moura (Portugal), with a capacity of 46 MW. It is expected to be fully grid-connected by December 2008.

Solar hot water

In the field of thermal solar energy (solar hot water), ACCIONA Solar has installed 14 MW to date, virtually all of which has been for other companies.

The company is the leader in the installation of this technology in Spain.

Energy efficient building

ACCIONA is also involved in the field of energy efficient buildings, incorporating solar technology as much as possible.

The most notable example of this is ACCIONA Solar’s head office, a building which consumes 52% less energy than a conventional building of the same characteristics, thanks to the use of numerous measures for using energy efficiently and making energy savings, covering 48% of its needs from photovoltaic solar power – electricity; thermal solar power – climate control; and biodiesel.

This means that the office is classified as a “zero emissions” building, as it can cover its energy requirements without emitting CO2.


In biodiesel and bioethanol

ACCIONA Energy works in the area of biofuels for transport, a sector which represents over 30% of the greenhouse gas emissions in the OCDE countries and 50% of the global oil demand (67% in the European Union).

The company has already presence in the field of biodiesel, with a 70,000-tonnes production plant in Navarra, and a 200,000-tonnes one under construction in Bilbao. It also owns a 26,000-tonnes bioethanol plant in Castilla-La Mancha (central Spain).

The European Commission has set the objective of a 5.75% quota for biofuels in road transport consumption by 2010. Spain has adopted that goal by establishing a 5.83% quota in the Plan for Renewable Energies, approved by the Government in 2005. The EU plans to increase that goal up to 10% in 2020.

Wind turbines

ACCIONA Windpower, a global supplier

ACCIONA Windpower, is the ACCIONA’s subsidiary company that works on the design, manufacture, field assembly and marketing of wind turbines,  based on the experience of the group to which it belongs in the operation and maintenance of wind power facilities worldwide. It produces 1,500 kW and 3,000 kW wind turbines which have been designed from the point of view of the wind farm operator interested in achieving the best performance throughout the working life of the machine.In 2007 ACCIONA Windpower produced 582 turbines (873 MW). This figure is higher than the company’s production in the three previous years and duplicates the 2006 figure (426 MW), thus consolidating its position in the world ranking of major wind turbine manufacturers. The company expects to finish this year with over 1,500 MW of new capacity installed.

For years after having launched the AW-1500, one of the most reliable wind turbines in the market of the megawatt segment, ACCIONA Windpower introduced the new AW-3000 at Windpower 2008 Exhibition in Houston (Texas, USA) last June. It is based on the same concept of strong, reliable and durable wind turbine as its successful predecessor and extent our capacity to meet the rising market expectations.

Four wind turbine assembly plants

ACCIONA Windpower has four wind turbine manufacturing facilities, two in Spain, one in China and one in the USA. Their total annual production capacity is 2,625 MW.

ACCIONA Windpower also has an assembly plant for hubs and other components in Toledo (Spain) and will build a blade production plant in Navarre (Spain) in 2008; its opening is planned for the end of the same year.

Turbines in wind parks in twelve countries

By the end of 2008 ACCIONA Windpower turbines will have been installed in wind parks in twelve countries: Spain, the US, Canada, Mexico, Australia, China, South Korea, Italy, Greece, France, the UK and Poland.

A good part of these projects have been (or will be) carried out by other companies with which ACCIONA Windpower has signed contracts for the supply of turbines. This modality will increase over the next few years.

Working on design since 1997

The technology developed by ACCIONA Windpower is the result of more than fourteen years of knowledge accumulated by one of the most technical teams in the world on the operation and maintenance of wind parks.

The ACCIONA Group’s experience and acumen gained from the management of wind parks containing thousands of wind turbines of different technologies installed in various countries has been the cornerstone to the succesful development of our technology.

Before launching series production of the AW 1500 the company installed three prototypes of a 1300 kW in 2000-2002, followed by twenty units of the same model in a wind park in Navarre.

Work on the series production of the 1.5 MW machine started in 2004. To date, over 2,000 units have been assemblied.

Abengoa Solar

Abengoa Solar

+34 91 330 06 69



At Abengoa, they believe that it is time to create a sustainable model of economic development
The overwhelming weight of scientific opinion is that climate change is a reality. At Abengoa Solar, they believe that it is their responsibility to develop and apply solutions that solve this major problem facing mankind.

Climate change is intensifying weather extremes, such as hurricanes, floods, droughts and desertification, and is radically changing ecosystems. If we do not develop alternatives to existing patterns of energy use, the consequences of climate change will get even worse.


Concentrated Solar Power

What is CSP energy?

Operating Principle

Solar Radiation Concentration


Generally speaking, C.S.P. technology is based on solar radiation concentration to produce steam or hot air which could then be used on conventional electric plants. Solar energy capture, which has a relatively low density, is one of the main challenges on the development of solar plants. For concentration, most of the systems use mirrors due to their high reflectivity.

Punctual and Linear Concentration

Punctual and lineal concentration could only benefit from direct radiation, and not from diffuse one as this latter could not be concentrated. Linear concentration is easier to install as it has fewer free degrees, but has a lower concentration factor and, therefore, could reach lower temperatures than punctual technology.


Types of Technology

Within C.S.P. technology, there exist different types of technology, being the most common tower technology, parabolic trough technology and dish Stirling technology.