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RE technology options:. Hydroelectric Solar Wind Geothermal Marine (Wave and Tidal) Biofuels (Biomass, Bioethanol and Biodiesel). Major Reference:.
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RE technology options: • Hydroelectric • Solar • Wind • Geothermal • Marine (Wave and Tidal) • Biofuels (Biomass, Bioethanol and Biodiesel)
Major Reference: Solar energy: Trends and enabling technologies (byV. Devabhaktuni, M. Alam, S.S.S.R. Depuru, R.C. Green II, D. Nims, C. Near) Renewable and Sustainable Energy Reviews, Vol. 19 (2013): 555–564
Average annual global solar energy The earth receives a huge amount of energy in the form of solar radiation. On average, it is 1,700 kWh/m2/year (= 194 W/m2) The total amount received on the planet’s surface is equal to approximately 10,000 times the global energy consumption.
Average annual global solar energy 7.5 7 6 5 4 3 Clear sky insolation, incident, horizontal surface (kWh/m2/day) Source: NASA 2008
Major solar energy conversion technologies: Solar Thermal (Solar T): is a technology by which sunlight is used to directly warm water or air without involving electricity. Concentrated Solar Power (CSP): is a technology by which sunlight is focused by mirrors or reflective lenses to heat a fluid in a collector at high temperature. Solar Photovoltaics (Solar PVs): are arrays of cells containing a semiconductor material that converts solar radiation into direct current (DC) electricity.
Major solar energy conversion technologies: Solar Thermal (Solar T): is a technology by which sunlight is used to directly warm water or air without involving electricity.
Solar Thermal: Solar water heaters Solar heating capacity was 185 GWh-thermal in 2011.
Solar Thermal: Solar water heaters • Passive solar water heaters • Active solar water heaters
Solar Thermal: Passive solar water heater - It consists of an absorption mechanism. - The absorption mechanism is typically some type of copper tubing (in various configurations) that are painted with a coating to improve efficiency. - Water (or air) is sent through the absorption piping system where it is heated.
Solar Thermal: Active solar water heater • It consists of the following: • - an absorption mechanism • - a transfer mechanism • - a storage tank
Solar collector Solar Thermal: Active solar water heater To taps Controller Tank Boiler Cold water feed Pump
Solar Thermal: solar water heaters Flat plate solar collection system Evacuated tube solar collection system
Major solar energy conversion technologies: Concentrated Solar Power (CSP): is a technology by which sunlight is focused by mirrors or reflective lenses to heat a fluid in a collector at high temperature.
Concentrated Solar Power (CSP): In CSP systems, sunlight is focused by reflective lenses to heat a fluid in a collector to high temperatures. I. Purohit, P. Purohit / Energy Policy 38 (2010) 3015–3029
CSP for electricity generation: Parabolic trough http://www.greenrhinoenergy.com/solar/technologies/cst_technologies.php
CSP for electricity generation: Parabolic trough A solarparabolic trough is constructed as a long parabolic mirror (usually coated silver or polished aluminum) with a Dewar tube running its length at the focal point. Sunlight is reflected by the mirror and concentrated on the Dewar tube. The fluid (eg. Oil) running through the Dewar tube is therefore heated up. Source: http://en.wikipedia.org/wiki/Parabolic_trough
CSP for electricity generation: Parabolic trough The trough is usually aligned on a north-south axis, and rotated to track the sun as it moves across the sky each day.
Solar Troughs Steam Turbine Thermal oil is circulated in a closed loop Electric Generator Steam Generator Condenser Cooling Tower CSP for electricity generation: Parabolic trough Solar energy trapped by solar troughs heats the thermal oil. Oil circulating in a closed loop heats high volumes of water to generate steam at high temperatures (up to 400oC). Steam turbine generates electricity (at about 30% conversion efficiency). Source: http://www.solarpanelsplus.com/parabolic-trough-collectors/
CSP for electricity generation: Parabolic trough Solar Energy Generating Systems (SEGS) consists of nine solar power plants (built between 1984 and 1990) in California's Mojave Desert, where insolation is among the best available in the US. • - 354 MW installed capacity • power 232,500 homes • have a total of 936,384 mirrors • cover more than 1,600 acres (6.5 km2) • lined up, the parabolic mirrors would extend over 370 km. • 3000 broken mirrors (mostly by wind) per year are replaced Source: http://en.wikipedia.org/wiki/Solar_Energy_Generating_Systems
CSP for electricity generation: Solar tower http://www.abengoasolar.com/corp/web/en/technologies/concentrated_solar_power/power_tower/index.html
CSP for electricity generation: Solar tower • - There is a central tower receiver surrounded by a field of mirrors (called heliostats) • The mirrors (tracking the angle of the sun) concentrate the solar radiation onto a central heat absorber situated in the tower. • The temperature of the fluid in the absorber on the tower can reach up to 500oC to 1000oC. • The fluid is used to heat water and run the steam turbine that produces electricity. http://www.greenrhinoenergy.com/solar/technologies/cst_technologies.php
CSP for electricity generation: Solar tower Solucar PS10 (in Spain) is a commercial solar thermal power tower-based plant http://en.wikipedia.org/wiki/Solar_power_tower
CSP for electricity generation: Solar tower Facts on Solucar PS10: • - Solar tower is 115 m high, 40-story tower where a solar receiver and a steam turbine are located • 624 movable mirrors (called heliostats) with 120 m2 surface area each • four years to build • cost 35 million Euros • 11 MW installed capacity http://en.wikipedia.org/wiki/PS10_solar_power_tower
CSP for electricity generation: If heat received could also be stored in a thermal storage media, the parabolic-trough and central tower CSP plants can reduce the effects of solar intermittency by producing electricity at night. • Storage media used are: • pressurized steam • concrete • molten sodium nitrate • molten potassium nitrate • purified graphite http://www.greenrhinoenergy.com/solar/technologies/cst_technologies.php