Concentrated Solar Power (CSP) Systems: Functionality, Types, And Environmental Challenges Essay.

You are required to write a report on Concentrated Solar Power (CSP) for the production of Electricity.

Your report must be laid out with the following sections clearly identified.

1.The Engineering principles behind the generation of Electricity from CSP with and without storage. You need to cover Parabolic Trough systems and the Power Tower system. You need to show the efficiencies achieved by the various CSP systems in operation.

2. Describe 2 practical systems (one of each type) that are in use and how they operate.

3. A summary of currently operating CSP locations throughout the world including Australia.

4. World CSP potential including the locations

5. Australian CSP potential including the locations

6. Discuss any environmental problems associated with CSP.

7. Discuss the Engineering challenges of CSP.

Basic Functionality of CSP System

The basic functionality of the CSP system is composed of various kinds of mirrors that collect the solar radiation which is said to be the collector system and it consist of the receiver that receives the concentrated solar radiation. This solar panel converts the thermal energy into thermal energy and it is further transferred into a heat transfer medium. Finally this heat energy is transferred into a mechanical energy through the steam generator. This finally is converted into an electric energy by means of the generator (International Energy Agency, 2014). The solar concentration must be improved in order to get the maximum heat or thermal power to run the engines efficiently.

One of the oldest and commercial methods used is PTC that was built by Cairo at the year of 1912. The first modern technology of PTC was used at California at the year of 1980 (EIA, U.S. Energy Information Administration, 2016). This system receives the solar radiation at the collector terminal on the focal line of the central receiver that has a parabolic-shaped mirror. This system consists of the parallel shaped mirror that is 150 meters long which is arranged in the form of the rows. These mirrors are about 6 meters wide (Firstsolar, 2015).  The direction of the system is held at the north-south, which is combined at a single-axis tracking mechanism. This mechanism allows the system to move at the east-west direction that moves by the rotation of the earth towards sun (Andersen, Mathews & Rask, 2009). The temperature of the system is kept under 400 °C since the synthetic oil decomposes with the high temperature that limits the maximum possible exploitation of the solar energy.  The efficiency of the system towards the production of electricity was about 14-16%. The parabolic trough collector technology is shown in the figure given below

Figure 1: parabolic trough collector technology

The system is composed of the flat mirrors that have heliostats with the separate tracks with the separate axes that get the concentration of the sun individually. The receiver of the system is located on the tower that tracks the sun individually on each tower.  The efficiency of the thermodynamic cycle could be increased since the central receivers could get the maximum temperature than the line-focusing system (Frass, 2014). This has an increased efficiency of about 20% (Blanco, 2009). Power tower system gets the water from the stream. This system also has the synthetic oil or molten salt as the primary HTF since the molten salt could promote a higher temperature up to 650 °C. The power system is shown in the figure given below

Types of CSP Systems

The solar system was first installed in diesel mini-grid in 2001. This project was highly supported by the Australian government that funds from the Renewable Energy Commercialization Program. The system consist of  500-sun concentrating dishes which will be about 130 square meter that promotes about 22% efficiency with the photovoltaic cells with the cooling system. Solar Systems also promoted further more CPV stations in diesel mini-grid towns, with all sites now fitted with Spectro lab multi-junction PV cells.

Figure 2: Power systems or Central Receivers

Jemalong Solar Thermal Station:

This power station is located in Australia. The type of technology used behind the station is Power tower that covers an area of about 10 hectares (McKenna, Richardson & Thomson, 2012). This station is operated by Vast solar. The Heliostat Solar Aperture area is about 15,000 square meter and Liquid sodium is used as a heat transfer fluid type. This was started at the year of 2017 and currently under operation.

Sundrop CSP project:

This power station is located in Port Augusta, Australia. The type of technology used behind the station is Power tower. The location heads 32°35′ 38.0″ South and 137°51′ 21.0″ East. The Heliostat Solar Aperture area is about 51,505 square meters. The turbine net capacity is 1.5 MW with the tower height of 127m. The output produced will be steam Rankine. This was started at the year of 2016 and currently under operation. The production of electricity of above 1700 MWh/year is by utilizing fresh water that is obtained by the process of desalination. This further runs the steam turbine for the production.

Genesis Solar energy project:

The power station is located at Blythe, California that utilizes the technology of parabolic trough. This currently operating plant was started in the year of 2014 by Genesis Solar LLC. They are located at 33°40′ North and 114°59′ West. There are about 1840 solar assemblies with 460 loops. The turbine has the net capacity of 250 MW. The output produced will be steam Rankine with the dry cooling method.

Solana Generating Station:

The power station is located at Phoenix, Arizona, which utilizes the technology of parabolic trough. . They are located at 32°55′ 0.0″ North and 112°58′ 0.0″ West and produces electricity generation of 944,000 MWh/yr. It is operated by Abengoa Solar Liberty Interactive Corporation. The solar collector assemblies cover an area of 2,200,000 square meters. The Net turbine capacity will be 250 MW. The storage type is of 2-tank indirect. This is currently in operation that has been started at the year 2013.

Jemalong Solar Thermal Station

SEGS VIII is one of the nine Solar Electric Generating Station plants in California’s Mojave Desert located at 35°1′ 54.0″ North and 117°20′ 53.0″ West. The solar field aperture area is about 464,340 m². The combined electric generating capacity of these plants, which use parabolic trough technology, is more than 350 megawatts. The Net turbine capacity is 89 MW. This currently operating plant was started in the year of 1989.

This currently utilizes the technology of parabolic trough and it is located at the Boulder city, Nevada. This is currently in operation that was started at the year of 2007. The solar resource utilized is 2,606 kWh/m²/yr. the location is exactly 35°48′ North and 114°59′ West. The solar field aperture covers an area of 357,200 square meters implemented with the Wet cooling method with the Net turbine capacity of about 75 MW.

• Aurora Solar Energy Project– Port Augusta
• Jemalong Solar Thermal Station– Jemalog, New South Wales
• Lake Cargelligo-  Lake Cargelligo, New South Wales
• Liddell Power Station– Liddell, New South Wales
• Sundrop CSP Project– Port Augusta

• ISCC Hassi R'mel – Hassi R’mel, Algeria
• City of Medicine Hat ISCC Project – City of Medicine Hat, Canada
• Solana Generating Station – Phoenix, Arizona, United States
• Genesis Solar Energy Project – Blythe, California
• Thai Solar Energy 1 – Huai Kachao, Thailand

6) Environmental Challenges:

Water issues:

These solar plants require large amount of space and sun light for the large Sun Belt hence it must be constructed at the arid and semi-arid regions. This large concentrated system requires maximum cooling equipments at the back end of the systems. This large amount of requirement of cooling system needs huge amount of water that could provide certain difficulties in the arid areas particularly at the MENA region (AFDB, African Development Bank, 2011). These areas experiences hardest water stress around the areas. Normal 50 MW parabolic trough system requires about 0.5 million meter cube of water every year for cooling. Moreover the agricultural irrigation lands needs these water quantities that could be utilized by the CSP at the semi-arid region.

One major advantage is that CSP plant could be located at areas with limited convenience or exceptional state. Hence the area such as the dessert areas could be used well for the construction of CSP rather than using biomass energy land. Moreover, arid region contains certain environmental aspects with biotopes and certain species that could be threatened (Fraunhofer ISE, Fraunhofer Institute for Solar Energy Systems, 2016). Moreover the arid region does not have a perfect climate situation, hence it may take a long time to overcome the difficulties that it’s facing. By terminating the dispersion routes and moderately separating the population it could reduce the animal and the plant population due to these solar systems.

Environmental factors are greatly affected due to the release of certain toxic substances that are emitted from the CSP plants. Parabolic trough uses synthetic organic heat transfer fluids that could be a mix of biphenyl and biphenyl-ether (IAEA, International Atomic Energy Agency, 2016). These chemical substances have a danger of catching fire at certain times and these substances could cause harm to the soil and create other pollutants. The resulting greenhouse gas emissions was found to be in the range 15–20 grams CO2-equivalent/kWh.

Although solar energy has a greater scope there are certain challenges faced by the market and engineers. The market sensitiveness has increased, the time value of energy will maximize to a large factor. Feed In tariffs produce various economical values that produce various incentives that could ignore the time-of-day values of the power (Hinkley, 2011). This could finalize the use of basic load systems. But the future needs a system to be reliable, flexible and the system should follow the load requirement.

Conlon says that FIT-supported solar plants may experience a rocky road with respect to the market dependent resiliency that does not need a complete redesign (Monteiro, Ramirez-Rosado, & Fernandez-Jimenez, 2013). This could increase the market value for the use of renewable as they appear to be the mainstream, which could have more responses to the market forces rather than subsidies like tax credit and FITs. They should act like other power generation systems. 

References:

Andersen, P.H., Mathews, J A., & Rask, M. (2009). Integrating private transport into renewable energy policy: The strategy of creating intelligent recharging grids for electric vehicles. Energy Policy, 37(7), 2481-2486.

AFDB, African Development Bank. (2011). Strategic Environmental and Social Assessment Summary. Renewable Energy and Global Rural Electrification Project (PERG). Retrieved from https://www.afdb.org/fileadmin/uploads/afdb/Documents/Environmental-andSocial-Assessments/EESS-Renouvelable%20et%20PERG-Resume_English.pdf

Blanco, M I. (2009). The economics of wind energy. Renewable and Sustainable Energy Reviews, 13(6), 1372-1382.

EIA, U.S. Energy Information Administration. (2016). Electric Power Monthly. Retrieved from https://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_6_07 _a

Firstsolar. (2015). First Solar Breaks Ground on Jordan’s Largest PV Plant. Retrieved from https://www.firstsolar.com/en/About-Us/PressCenter/Blog/2015/June/First-Solar-Breaks-Ground-on-Jordans-Largest-PVPlant

Frass, L.M. (2014). Low-Cost Solar Electric Power. Cham: Springer International Publishing Switzerland.

Fraunhofer ISE, Fraunhofer Institute for Solar Energy Systems. (2016). Photovoltaics Report. Freiburg. Retrieved from https://www.ise.fraunhofer.de/de/downloads/pdffiles/aktuelles/photovoltaics-report-in-englischer-sprache.pdf

Hinkley, J. et al. (2011), Concentrating Solar Power-Drivers and Opportunities for Cost-competitive Electricity, CSIRO, Victoria.

IEA, International Energy Agency. (2014a). Technology Roadmap. Solar Photovoltaic Energy. 2014 Edition. Paris. Retrieved from https://www.iea.org/publications/freepublications/publication/TechnologyRo admapSolarPhotovoltaicEnergy_2014edition.pdf

IAEA, International Atomic Energy Agency. (2016b). PRIS – Power Reactors Information System. BARAKAH-1. Retrieved from https://www.iaea.org/PRIS/CountryStatistics/ReactorDetails.aspx?current=105 0

McKenna, E., Richardson, I., & Thomson, M. (2012). Smart meter data: Balancing consumer privacy concerns with legitimate applications. Energy Policy, 41, 807-814.

Monteiro, C., Ramirez-Rosado, I.J., & Fernandez-Jimenez, L.A. (2013). Short-term forecasting model for electric power production of small-hydro power plants. Renewable Energy, 50, 387-394.