SOLAR ENERGY POTENTIAL AND USAGE

1. SOLAR ENERGY POTENTIAL AND USAGE ANASTASIYA IVANOVA, SIIM-ERIK ALAAMA, OKOLIE JUDE SUSTAINABLE ENERGY TECHNOLOGIES,2017

2. Outlines • Nature of Solar Energy • Solar Energy usage and potential • Working principles and Technological Development • Pros and Cons of Solar Energy • Current research in Solar Energy • Conclusion

3. Solar energy is the radiant energy produced by the Sun. It is both light and heat. Nature of solar energy

4. The sun provides 99.98% of the energy for our planet (the rest is geothermal); • The sun is a star that consists of 71 % Hydrogen, 27% Helium and 2% solid matter; • The energy emitted by the sun is approximately 63 MW for every m² of its surface, about 3.72 x 10²⁰ MW in total; • At the mean distance between Earth and sun of 150 million kilometres, the flux of the solar radiation reaching the Earth’s atmosphere is 1,367 W/m² (World Meteorological Organisation, 1982); Nature of solar energy

5. The Sun releases energy at a mass–energy conversion rate of 4.26 million metric tons per second, which produces the equivalent of 37,2 septillion watts (3.72×1026 W) per second; • The Earth receives 174 petawatts (PW) of solar radiation at the upper atmosphere, 30% of that is reflected back to space and the rest is absorbed by clouds, oceans and land masses Nature of solar energy

6. Nature of solar energy

7. The sun emits very intense radiation that has short wavelengths: • Most of the sun's radiation is in the visible wavelengths (0.4 (violet) to 0.7 (red) micrometers); • Nearly 37% of the sun's radiation is in the slightly longer infrared wavelengths (0.7 to 1.0 micrometers). It is not visible to humans but it is very intense; • Only about 7% of the sun's radiation is in the ultraviolet range. Nature of solar energy

8. Nature of solar energy • When 1367 W/m2 is arriving above the atmosphere (as when the earth is one astronomical unit from the sun), direct sun is about 1050 W/m2, and global radiation on a horizontal surface at ground level is about 1120 W/m2 ; • The actual figure varies with the Sun's angle and atmospheric circumstances. Ignoring clouds, the daily average insolation for the Earth is approximately 6 kWh/m2 = 21.6 MJ/m2. • The output of a photovoltaic panel, partly depends on the angle of the sun relative to the panel. One Sun is a unit of power flux, not a standard value for actual insolation. Sometimes this unit is referred to as a Sol, not to be confused with a sol, meaning one solar day.

9. Potential of solar energy • 3 850 000 exajoules (EJ) is absorbed by the atmosphere and the Earth’s surface yearly; • One hour of insolation is the equivalent to more than the world’s energy consumption for an entire year. Solar energy is by far the largest energy resource on the Earth; • Major obstacle: solar is an intermittent energy source; • Geography affects solar energy potential greatly, but constantly improving technologies can increase the potential of areas with less direct sunlight.

10. Solar Energy usage and potential World map of direct solar irradiation

11. Solar Energy usage and potential • In 2015, cumulative photovoltaic capacity increased by 48,1 GW and reached at least 227,1 GW; • Right: top 10 countries based on installed PV capacity (2015); • Installed PV capacity in EU (2015): 94 570 MW.

12. Solar Energy usage and potential Total global PV capacity, GW

13. Solar Energy usage and potential Annual PV installations, GW

14. Solar Energy usage and potential Solar energy production in % of national electricity demand

15. Technologies • Thermal solar power • Water heating • Heating, cooling and ventilation (HVAC) • Electricity production • Photovoltaics (PV) • Concentrated solar power (CSP)

16. Solar water heating • Using direct sunlight to heat water • Right: active solar water heating system

17. Evacuated tube solar collector: Generate heat from direct and not direct solar radiation Flat plate solar collector: Generate heat only from direct solar radiation

18. Heating, cooling and ventilation • Accounts for 50% of energy used in residential buildings. • Thermal mass – exterior material that stores heat from the Sun. • A solar chimney – a vertical shaft connecting the interior and exterior of a building. • Plants can be used to control solar heating and cooling.

19. Photovoltaics • Solar cells converting sunlight directly into electricity • Crystalline Silicon solar cells • Mono-Si • Multi-Si • Thin film solar cells • CdTe • CIGS • CdS • Perovskite solar cells • Organic and polymer solar cells

22. PV Applications • Rooftop PVs • Building-integrated PVs (BIPVs) • PV thermal systems (PVTs)/Building-integrated PV thermal systems (BIPVTs) • Solar power stations • Rural electrification • Standalone solar powered devices • Transport • Space applications

23. Concentrated solar power (CSP) • Solar power by using lenses to concentrate a large area of thermal energy onto a small area.  • Concentrated light is converted to heat (using molten salt), which drives a a steam turbine • Heat storaged in molten salt allows some solar thermal plants to continue to generate after sunset.

24. CSP plant scheme

26. Current Research in Solar cells Perovskite solar cells • These perovskite films are highly crystalline materials that can be formed by a large number of different chemical combinations and can be deposited at low cost

27. Main Drawbacks • High cost of installation compared to the cost of non-renewable sources. • Large area of installation requirements. • Efficiency depends on the location of the sun • No solar energy will be produced during nighttime although a battery backup system and/or net metering will solve this problem.

28. Advantages of Solar Energy Environment friendly Solar Energy is clean, renewable (unlike gas, oil and coal), sustainable and helping to protect our environment. Therefore Solar Energy does not contribute to global warming, acid rain or smog. It actively contributes to the decrease of harmful green house gas emissions. Low/ no maintenance Solar Energy systems are virtually maintenance free and will last for decades. Once installed, there are no recurring costs. They operate silently, have no moving parts, do not release offensive smells and do not require you to add any fuel. More solar panels can easily be added in the future when your family's needs grow.

29. Conclusion • Solar Energy is a good and feasible alternative to fossil fuels • Immense research to improve the efficiency of solar cells • A 1-kilowatt home solar system will prevent approximately 170 lbs. of coal from being burned, 300 lbs of CO2 from being released into the atmosphere and 105 gallons of water from being consumed each month! Tools for adoption and acceleration • Penalizing extractive and polluting fossil-fuel energy • Create Incentives • Consumer tax deductions • Production Tax credits • Invest in R&D

30. References • http://www.iea-pvps.org/fileadmin/dam/public/report/PICS/IEA-PVPS_-__A_Snapshot_of_Global_PV_-_1992-2015_-_Final_2_02.pdf • http://www.alternativeenergyhq.com/wp-content/uploads/2015/10/SolarGIS-Solar-map-DNI-World-map-en.png • http://www.sunisthefuture.net/wp-content/uploads/2013/04/Sunisthefuture-design-M-Solar-Cell-Efficiencies3.jpg • https://energy.gov/sites/prod/files/styles/media_energy_gov_wysiwyg_fullwidth/public/CSP%20diagram.jpg?itok=9fcPYwj1 • http://needtoknow.nas.edu/energy/energy-sources/renewable-sources/solar/ • http://www.universetoday.com/73693/what-is-solar-energy/ • https://phys.org/news/2016-10-advances-solar-cell-technology.html