MTLE 4962- Energy, Environment and Economy Ziyu (Grace) Zhou Solar Energy MTLE 4962- Energy, Environment and Economy Ziyu (Grace) Zhou

Overview What is solar energy? How does solar energy generated? Photovoltaics Why do we care about solar? Common applications Money What is the future of solar? Solar Energy Trees Pros and Cons Technological Challenges Question and Discussion http://graphican.deviantart.com/art/Green-Energy-78673552

What is solar energy? Solar energy is defined as energy derived from the sun in the form of solar radiation First observed in 1839 by Alexandre Edmund Becquerel Bell’s Lab developed first PV device in 1954 http://www.huffingtonpost.com/laiza-king-/how-solar-energy-is-chang_b_10071270.html http://www.digitaltrends.com/cool-tech/china-solar-energy/  In 1954, Bell Labs in the U.S. introduced the first solar PV device that produced a useable amount of electricity, and by 1958, solar cells were being used in a variety of small-scale scientific and commercial applications.

How does solar energy generated? Use photovoltaic cell (semiconductor material) to transfer solar energy into electricity Photons strike and ionize semiconductor material on the solar panel, causing outer electrons to break free of their atomic bonds. The electrons are forced in one direction creating a flow of electrical current Solar cells are not 100% efficient due to reflection and heat generation https://in.pinterest.com/explore/semiconductor-diode/

Why do we care? - Applications Solar Powered Transportation Solar Technologies Solar Heating Solar Lighting Rooftop Solar

5 Common Applications Solar Powered Transportation Railroads, subways, buses, planes and cars Solar Impulse 2 (12-2009) long-distance all-solar aircraft Solar buses in China (07-2012) Solar Spirit in Australia Student designed solar car in 2011, 2013 and 2015 Solar impulse 2:  three-day trek across the Pacific Ocean (62 hours) http://news.energysage.com/most-common-solar-energy-uses/

5 Common Applications Solar Powered Transportation Solar Technologies Solar powered charges E.g. Anker’s PowerPort Solar Flashlights Wearable solar E.g. Future Apple Watch Anker’s powerport available in amazon: https://www.amazon.com/Anker-2-Port-Universal-PowerPort-Charger/dp/B012YUJJM8/ http://news.energysage.com/most-common-solar-energy-uses/

5 Common Applications Solar Powered Transportation Solar Technologies Solar Heating Solar water heater Solar space heater http://news.energysage.com/most-common-solar-energy-uses/

5 Common Applications Solar Powered Transportation Solar Technologies Solar Heating Solar Lighting Outdoor solar lighting (energy storage) Join with LED or other lighting technologies http://news.energysage.com/most-common-solar-energy-uses/

5 Common Applications Solar Powered Transportation Solar Technologies Solar Heating Solar Lighting Rooftop Solar Save utility cost ! http://news.energysage.com/most-common-solar-energy-uses/

Why do we care？-- To Save Money ! https://cleantechnica.com/2014/02/03/much-can-solar-panels-save/

What is the future of solar? https://in.pinterest.com/explore/semiconductor-diode/

New Technology – Solar Energy Trees Tree Leaves - Organic Solar Cells Each leaf is a power converter Multi-converter system: collect energy from solar, wind and heat temperature  Trunks – 3D Printed Wood-based Biocomposites http://www.alternative-energy-news.info/3d-printed-solar-energy-trees/

Pros and Cons Advantages Disadvantages 1. Renewable/Sustainable 1. Intermittent 2. Abundant/Good Availability 2. Energy Storage (Expensive) 3. Low Maintenance 3. Pollution (solar panel manufacture) 4. Silent 4. Exotic Materials vs Efficiency 5. Government Support 5. Require Space …… Crystalline Silicon are used most often, but are searching new mateirals

Solar Energy Challenges Energy Storage Cost Semiconductor material used as solar cell Solar panel manufacture Electricity generation? Low Efficiency Only about 20% - 40% efficiency Social Awareness Reliability Pre-investment 33.16% efficiency for Crystalline Si; 4-junction GaInP/GaAs//GaInAsP/GaInAs solar (2015) – 44% efficiency; thin film material: Cadmium telluride or Copper indium gallium selenide

Question and Discussion How to improve solar energy efficiency? Technology Improvements How to make solar energy more accessible to the general public? How to further reduce the cost? Do you want solar energy?

Reference 1. "Green Energy." On DeviantArt. Accessed February 13, 2017. http://graphican.deviantart.com/art/Green- Energy-78673552. 2. "Solar energy." Dictionary.com. Accessed February 13, 2017. http://www.dictionary.com/browse/solar-energy. 3. King, Laiza. "How Solar Energy Is Changing the World Using New Technologies." The Huffington Post. Accessed February 13, 2017. http://www.huffingtonpost.com/laiza-king-/how-solar-energy-is-chang_b_10071270.html. 4. Http://www.facebook.com/luluchang79. "China is now the world’s largest solar power producer." Digital Trends. February 06, 2017. Accessed February 13, 2017. http://www.digitaltrends.com/cool-tech/china-solar- energy/. 5. Photovoltaic (Solar Electric)." SEIA. Accessed February 13, 2017. http://www.seia.org/policy/solar- technology/photovoltaic-solar-electric. 6. "Semiconductor Diode." Pinterest. Accessed February 13, 2017. https://in.pinterest.com/explore/semiconductor-diode/. 7. "How Much Are Solar Panels? Wrong Question. Ask How Much Solar Panels Can Save You." CleanTechnica. February 03, 2014. Accessed February 13, 2017. https://cleantechnica.com/2014/02/03/much-can-solar-panels- save/. 8. Richardson, Luke. "How is Solar Energy Used? The 5 Most Common Examples of Solar Power." EnergySage. December 14, 2016. Accessed February 13, 2017. http://news.energysage.com/most-common-solar-energy- uses/. 9. "3D Printed Solar Energy Trees." AENews. Accessed February 13, 2017. http://www.alternative-energy- news.info/3d-printed-solar-energy-trees/. 10. Agnes Peterson et al. "Solar Energy Pros and Cons." Energy Informative. Accessed February 13, 2017. http://energyinformative.org/solar-energy-pros-and-cons/. 11. "Why It Is Not More Widely Used." Problems With Solar Energy. Accessed February 13, 2017. http://www.solarpoweristhefuture.com/problems-with-solar-energy.shtml.