Business Units
April 2009
Solar
On Friday
January 30, members of the EU parliament, accompanied by some representatives
from national and regional parliaments and administrations, and by members
of the organizing body Estela (European Solar Thermal Electricity Association),
toured the Abengoa Solar facilities in the company of the main project
experts who explained the latest technological advances in the sector to
them.
The participants, split into small groups, went up to contour height 30 of the PS10 tower to view the location of each of the plants and projects under development at the Platform. They then visited the control room where the technical details for operation and maintenance of the plant were explained to them.
At a working breakfast, the creation of a stable regulatory framework for the renewable energies sector, solar and bioenergy, was championed, to allow long-term development of the market. Without this framework, it will be impossible to establish a future for research and development work. The company’s managers reminded the visiting party that the Solucar Platform is a world reference site where most of the solar technologies currently in existence are to be found.
The visit was a complete success. The EU parliament members were greatly impressed by the dimensions, technologies and functioning of the plants and the in-depth explanations given on the same. Some of the members of the party mentioned the visit at the Renewable Energy Week, held in Brussels (Belgium) a week later.
Abengoa
Solar’s Institutional Relations Officer, Ricardo Abaurre, and the
Operations Manager, Valerio Fernandez, accompanied the members of the ecological
society on their tour of the Platform facilities, and explained the different
solar technologies operating there.
The Platform, in Sanlucar la Mayor, will be completed by 2013. With 300 MW installed output, it will provide clean electricity to 153,000 homes while avoiding emission of 185,000 t/year/CO2 (4 million tons during its operating life).
Its customers include:
Steinway & Sons,
NY.- Industrial solar installation to control building
humidity by means of two-phase absorption coolers for summer, and steam
generators in winter.
Arizona State Department of Energy. - Industrial solar installation for hot water.
Frito Lay, California. - Industrial solar system to produce steam that is utilized to heat oil to fry potato crisps.
Universidad Cochise, Arizona. - Industrial solar installation for heating and cooling.
Fort Sam Houston, Texas. - Industrial solar system to heat water and cool.
Federal correctional institution of Arizona. - Solar installation to heat water.
Installations
Abengoa Solar IST (ASI) heat production systems are designed,
manufactured and installed pursuant to ISO-9001 (International Standardization
Organization). Furthermore, ASI trusts in development and innovation thus
assuring its customers benefit from the latest technological developments.
ASI’s collector system has been proven and evaluated by Sandia (Dudley,
1995) in the US, and by DLR (Krueger, 2000) in Germany.
Collectors
The parabolic-trough collectors are of flexible design. The
collector systems reach temperatures ranging from 50 to 250ºC to meet
different needs, be it to produce hot water, steam or for cooling.
Abengoa Solar IST offers several trough models: small-size collectors for small rooftop installations and larger collectors for ground installations. When the need is greater, the collectors of solar power plants are utilized. ASI’s collectors are resistant, lightweight and do not utilize costly materials and, furthermore, come ready for immediate installation.
In June 2008, the first module assembly shop at the Solucar Platform came into operation; the second shop commenced operations in early fall.
The shops are the result of a project that took the entire process into consideration: from collector design, manufacturing of components, transportation and assembly, right up to field installation of the modules. The assembly activity has been designed in accordance with a “Lean manufacturing” system, with the following aims:
The collector module structure utilized in parabolic-trough technology plants is of Abengoa Solar design, made to simplify assembly and facilitate transportation from the factory to the warehouses, and has resulted in optimization of the entire process and significant cost savings.
To ensure assembly has been done correctly, the points where the structure connects with the mirror are controlled by photogrammetry at a point in the assembly chain.
Once the modules have been mounted, they are transferred to the field for positioning in the three parabolic-trough technology power plants under construction at the Solucar Platform. Each is a 50 MW plant comprising some 300,000 m2 of mirrors on an overall 115 hectare site, which represents 4,320 modules, 12.5 m long with a 5.7 m opening. In all, the three plants will have 12,960 modules.
Installation of the Solnova 1 field was completed in Januray 2009, and the Solnova 3 field is at a very advanced stage.
Aimed
at stimulating the economy and job creation, the package includes $4 billion
to guarantee loans for renewable energy projects, especially solar. The
industry’s representatives estimate that with said bill some 67,000
jobs will be created in the solar energy sector in 2009 and an overall
119,000 jobs over the next two years.
According to Rhone Resch, President of the Solar Energy Industries Association, “the provisions included in the solar energy plan will allow us to create new opportunities for the country’s enterprises and will keep the economic engine running”.
Through a financial assistance program, the promoters of renewable energy projects will be able to apply for certain temporary assistance to facilitate financing of their projects. However, the regulations that will govern these aid plans and ensure rapid implementation have yet to be established.
The stimulus package also includes energy financing measures including an $11 billion investment in the “smart distribution networks” program, aimed at developing – by implementing new technologies – a more efficient and less costly energy distribution grid. In addition, $6.3 billion will be allotted to energy efficiency and conservation of grants, and $2.5 billion to renewable energies research and development activities.
These
type power plants are an appealing option due to their low cost: installation
costs, rapid construction, more than 50% efficiency, and possibility of
high output.
In addition, the fluctuation in oil prices, growing world sensitivity to sustainable development as well as the international agreements enforcing greenhouse gas emission reductions, are bringing these type of power plants to the fore in relation to solar thermal technologies. Abengoa is constructing two plants, one in Algeria and the other in Morocco. The solar technology employed consists of an Abengoa Solar-designed parabolic-trough collector field.
Combined-cycle solar power plants with gas-solar system are based on hybrid operation through integration of a solar field in a combined cycle. Operation is similar to that of a conventional combined cycle. Electric energy is generated by two thermodynamic cycles – the Brayton cycle (gas turbine) and the Rankine cycle (conventional water/steam turbine cycle).
The gas turbine consists of an air compressor, a combustion chamber and an expansion chamber. The compressor compresses the air at high pressure once it has been passed though a filter to remove particles. The compressed air is combined, in the combustion chamber, with a fossil fuel (generally natural gas due to its low CO2 emissions and invaluable SO2 during combustion). Combustion occurs under temperature and pressure conditions that allow optimization of process performance and lower environmental impact.
The combustion gases from the gas turbine are forwarded to the heat recovery boiler (HRSG) where its residual energy is transferred to the water circulating in the pipes, and steam is thus produced. The gases are returned to the atmosphere via a stack.
In the gas turbine, the thermal energy is transformed into mechanical energy (2/3 is consumed in the compressor and the rest drives the electric generator connected to the gas turbine to produce electricity).
The steam is expanded in the steam turbine and turns the mechanical rotation energy into medium voltage and high voltage electricity. Subsequently, the voltage is raised in the transformers to reduce the energy losses on the transportation network. The implementation of this technology tends to connect both turbines to the same axis, to drive the same electric generator together.
The steam that exits the turbine is liquefied in the condenser. The cooling system may be open (river or sea) or closed (cooling tower). Lastly, the condensed steam is pumped to the heat recovery boiler to start the cycle all over again.
The integration of the solar field into the low temperature cycle (steam turbine) of a combined cycle allows increasing of the heat transferred to the water, thus increasing the steam generation capacity. As a result, higher performance of the cycle and a reduction in greenhouse gas emissions is achieved upon part of the fossil fuel being substituted by solar energy, and up to 22% reduction is achieved in operating costs and global costs of the solar thermal electricity.
These systems could attain a solar capacity equivalent to between 30 and 40 MWe and are appealing as a means to introduce solar technology into the electric energy market. Figure 1 shows a layout of a hybrid plant based on gas-solar combined-cycle technology, where the solar field comprises parabolic trough collectors.
Figure 1. Layout of an integrated solar combined cycle (ISCC) power plant