Renewable Energy, Basic Concepts and some Solar Science

1. Renewable Energy, Basic Concepts and some Solar Science Unit 4 Source:

2. Use Policy • This material was developed by Timothy J. Wilhelm, P.E., Kankakee Community College, with funding from the National Science Foundation as part of ATE Grant No. 0802786. • All materials in this presentation are designed and intended for educational use, only. They may not be used for any publication or commercial purposes. Source:

3. Author, Editors/Reviewers • Author: Timothy J. Wilhelm, P.E., Kankakee Community College • Editors/Reviewers: • Chris Miller Heartland Community College Source:

4. Objectives • Students will be able to differentiate between “renewable” and “non-renewable” energy resources, list specific examples of each, and explain why these examples are categorized as they are (renewable vs. non-renewable). • Students will be able to discuss the idea of “renewable energy,” using terms and ideas related to natural or ambient flows of energy, and natural or ambient energy conversions. Source:

5. Objectives • Students will be able to, in very simple terms, how and why the Sun is the fundamental energy resource for most (if not all) of our modern renewable energy conversions, including biomass, wind, hydro-gravitational, solar-thermal, and solar-photovoltaic. • Students will be able to, in very simple terms, describe and discuss the cyclic changes in the sun’s position in the sky, on a daily basis, seasonal basis, and annual basis. Source:

6. Review of Basic Concepts • Non-renewable energy resources are energy laden commodities that are finite or limited in supply, i.e. coal and petroleum. • Renewable energy resources are based on energy supplies that are NOT finite or limited (so long as the Earth keeps spinning and the Sun keeps shining!).

7. Review of Basic Concepts • Sustainable/renewable energy technologies are (in one way or another) forms of SOLAR energy… • Biomass conversion accesses stored solar energy, • Hydro-electric gennies access the impact of solar energy, • Wind gennies access the impact of solar energy, • Solar-thermal energy is obviously solar-sourced, • Solar-photovoltaic is also directly solar-sourced.

8. Review of Basic Concepts • Energy flows, or moves… • From areas of concentration to areas of lack; • From areas of high temperature to areas of low temperature; • From areas of high pressure to areas of low pressure; • From areas of high voltage to areas of low voltage; • …until the concentration, level, or magnitude is equal in both areas.

9. Review of Basic Concepts • There are ongoing, natural and ambient energy flows and energy conversions taking place, constantly, within our natural world; example… A never-ending stream of energy flows from the Sun (high concentration of energy) to the Earth (low concentration of energy), and shortwave electromagnetic radiation is converted into heat energy.

10. A New Look at “Renewable” Energy • Non-renewable energy conversions involve quickly extracting stored energy that was converted into its stored form many, many years ago, with the original storage-conversion often taking place over very long periods of time. Non-renewable energy conversions also, typically, exhaust “pollutants” into the natural environment. • Renewable energy conversions involve tapping into the ambient energy flows of the natural world, in “real time” (or short-cycle time), with minimal disruption of the natural system.

11. A New Look at “Renewable” Energy • Example: (From a previous slide) A never-ending stream of energy flows from the Sun (high concentration of energy) to the Earth (low concentration of energy), and shortwave electromagnetic radiation is converted into heat energy. A solar-thermal absorber collects and converts the Sun’s radiations, giving us a small zone of USEFUL, high-temperature heat energy. Ultimately, this heat energy goes back into the ambient surroundings, just as if the solar collector had never been there.

12. Brief Small-Group Discussions • Start with the non-renewables package. • With the other folk(s) at your table, go through each energy resource, read each alleged fact, and determine if it is an advantage, a disadvantage, or an indifferent fact. • Note any of the alleged facts on which you cannot agree how to categorize it. We’ll discuss these as a large group. • Repeat the process for the renewables package.

13. Brief Small-Group Discussions

14. Summary of Small-Group Discussions • For which alleged facts did you have disagreements on categorization? • Were there any of the alleged facts that you found surprising, or otherwise interesting? • Looking at all these alleged facts, as a whole, did you come to any interesting conclusions or have any noteworthy thoughts? What were they?

15. Basic Solar Science Source: http://www.freshnews.in/wp-content/uploads/2009/12/Sun-faces-Tsunami-waves-300x300.jpg

16. September 23rd, 2010 • What is special about that impending date? • It is the Equinox…the Vernal (Spring) Equinox in the northern hemisphere…the Autumnal (Fall) Equinox in the southern hemishpere. • What does that mean? • “All over the world,” there are (sort of) 12 hours of daylight and 12 hours of night.

17. Equinox Source: http://mappemonde.mgm.fr/num20/internet/jegF4.jpg

18. Our Summer Solstice Source: http://mappemonde.mgm.fr/num20/internet/jegF4.jpg

19. Our Winter Solstice Source: http://mappemonde.mgm.fr/num20/internet/jegF4.jpg

20. Why does the Sun’s Apparent Position Change with the Seasons? Basic Earth-Solar Geometry • Rotation -- Daily • Revolution -- Annually • Declination – The axis of the Earth’s rotation is NOT perpendicular to its plane of revolution (its orbit) • Precession – once every 25,920 years

21. The Cause-and-Effect Relationships of Precession are only Speculative.

22. Rotation Results in the Diurnal Cycle Source: http://www.wingmakers.co.nz/images/Earth-Moon

23. Revolution and Declination Combine to Create the Seasons Source: http://www.free-picture-host.com/images/ri2Kdx1240661879.jpg

24. Earth is Closest to Sun in the Winter! Source: http://2.bp.blogspot.com/_-3jEECtuwYw/TCAQR3OUqRI/AAAAAAAAASs/9huAnYHwGqQ/s320/img_news_solstice_scheme.gif

25. Why is it COLD in the Winter? • Fewer hours of sunlight. • Sun’s radiation hits at a sharp angle, as opposed to straight-on perpendicular. This yields less energy per unit of area. • At the sharp winter angle, the Sun’s radiation has to travel through more of the Earth’s atmosphere, which deflects and absorbs more energy than in Summer…less energy reaches the Earth’s surface.

26. The Atmospheric Path of the Sun’s Rays

27. How Much Solar Energy Actually Reaches the Earth (top of the atmosphere ) The Solar Constant

28. How Much Solar Energy Actually Reaches the Earth (average at the surface, on a clear day – Standard Test Conditions) Peak Sun = 1,000 Watts/meter2 Source: http://ellsworthme.org/MESEA/SarahSun2.gif

29. Basic Solar Energy Principles • The more “incident” the radiation, the more energy per unit area. • The less atmospheric travel, the more energy per unit area. (Boulder vs. Miami?) • The less the cloud cover, the more energy per unit area. • The longer the exposure time, the greater the energy transferred.

30. The Variable Solar Sky-Path

31. The Variable Solar Sky-Path

32. The Idea of “Peak Sun-Hours” Source: http://www.solarexpert.com/images/Daily-sun-profile.jpg

33. Seasonal Peak Sun-Hour Charts

34. Solar Site-Analysis Tools Source: http://img01.static-nextag.com/image/Gaiam-Hand-Held-Solar/1/000/005/292/917/529291776.jpg

35. Solar Site-Analysis Tools

36. Energy from the Sun… • …heats un-shaded portions of the oceans’ and the land masses’ surfaces. In turn, this… • …creates areas of less-dense and more-dense air in the atmosphere. In turn, this… • …creates convection currents in the atmosphere, known as “wind” currents. • Wind Energy involves tapping this natural energetic flow, and converting it to a useful form of energy!

37. Source: http://newsinthesun.com/wp-content/uploads/2009/11/tenerife-wind-farm.jpg/

38. Energy from the Sun… • …heats un-shaded portions of the oceans’ surfaces. In turn, this (along with other influences)… • …creates areas of less-dense and more-dense water in the ocean. In turn, this… • …creates convection currents in the oceans, known as ocean currents. • Ocean-Current Energy involves tapping this natural energetic flow, and converting it to a useful form of energy!

39. Source: http://www.bionomicfuel.com/wp-content/uploads/2008/10/underwater-energy-sources_1.jpg

40. Energy from the Sun… • …heats un-shaded portions of the oceans’ surfaces. In turn, this… • …causes the waters of the ocean to evaporate, and the less-dense moist-air at the ocean’s surface is forced upward into the higher atmosphere. In turn, we see… • …the formation of clouds, which precipitate rain on the mountain tops. Gravity pulls this fresh rain water downhill. • Hydro-Electric Energy involves tapping this natural energetic flow, and converting it to a useful form of energy!

41. Source: http://www.ecologiae.com/wp-content/uploads/2010/11/diga-idroelettrica.jpg

42. Energy from the Sun… • …heats un-shaded portions of the earth’s surface. In turn, this… • …energy is absorbed by the green plants growing on the earth’s surface. In turn, this… • …radiant, solar energy is STORED within the bodies of the plants, using rain from atmospheric moisture, carbon from the atmospheric gases, and minerals from the soil. • Biomass Energy involves tapping this natural, stored energy, converting it to a different, useful form of energy!

43. Source: http://slightlychristopher.files.wordpress.com/2010/09/moonshine_still_sugar_valley-e1284861615897.jpg?w=550&h=359

44. Energy from the Sun… • …comes to the Earth as “shortwave” electromagnetic radiation. When it strikes dark surfaces… • …it is absorbed by those materials and converted into heat energy, and is re-radiated as long-wave infrared radiation. • Solar-Thermal Energy involves tapping this natural energetic flow from the Sun, and converting it to a useful form of energy, and moving it to a needed location!

45. Source: www.ekosklep.ekologika.com.pl

46. Energy from the Sun… • …comes to the Earth as “shortwave” electromagnetic radiation. When it strikes SPECIAL dark surfaces… • …it is absorbed by those SPECIAL materials and converted directly into electrical energy. • Solar-Photovoltaic Energy involves tapping this natural energetic flow from the Sun, and converting it to a useful form of energy, and moving it to a needed location!

47. Source: http://www.bionomicfuel.com/wp-content/uploads/2009/11/using-solar-panels-for-electricy-generation_1.jpg

48. Energy from the Sun… • …AND from other sources within our universe, comes to the Earth as VERY “shortwave” electromagnetic radiation. When it strikes SPECIAL resonant devices… • …it is absorbed by those SPECIAL devices and converted into energetic vibrations of a useful frequency. • “Radiant” Energy involves tapping this natural energetic flow existing in space, and converting it to a useful form of energy!

49. Source: http://static.squidoo.com/resize/squidoo_images/-1/draft_lens7861661module66370861photo_1257184716Radiant_Energy_Device.jpg

50. Conservation FIRST!!! Always enact and employ the principles of “Energy Conservation” BEFORE using any “Renewable Energy” technologies!!!