Wireless power transmission involves transmitting energy from one place to another without wires. It has been studied since the 1940s using methods like microwave transmission and rectennas. Recent projects aim to transmit solar power to Earth from satellites using microwaves and large rectennas. Wireless power provides advantages over wired transmission like reliability, efficiency, and ability to reach remote locations. For it to be widely implemented, further developments are needed like lower launch costs and more government/private sector support.

1. Wireless Power Transmission Presented by Shubham Jain 0809010094 Department of Computer Science Engineering IEC College of Engineering and Technology, Gr.Noida

2. Overview What is wireless power transmission(WPT)? Why is WPT? 1940’s to Present Microwave transmission Rectenna Applications Space-based solar power SPS 2000 Advantages Conclusion References 4/20/2011 Wireless Power Transmission 2

4. In India, it exceeds 40%4/20/2011 Wireless Power Transmission 3

5. Why WPT? Reliable Efficient Fast Low maintenance cost Can be used for short-range or long-range. 4/20/2011 Wireless Power Transmission 4

6. 1940’s to Present World War II developed ability to convert energy to microwaves using a magnetron, no method for converting microwaves back to electricity 1964 William C. Brown demonstrated a rectenna which could convert microwave power to electricity

7. Microwave transmission Microwave transmission refers to the technology of transmitting information by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimeters; these are called microwaves. This part of the radio spectrum ranges across frequencies of roughly 1.0 gigahertz (GHz) to 30 GHz. These correspond to wavelengths from 30 centimeters down to 1.0 cm.

8. Microwave Power Transfer(MPT) Cont. Transfers high power from one place to another. Two places being in line of sight usually Steps: Electrical energy to microwave energy Capturing microwaves using rectenna Microwave energy to electrical energy 4/20/2011 Wireless Power Transmission 7

9. MP T (cont.…) AC can not be directly converted to microwave energy AC is converted to DC first DC is converted to microwaves using magnetron Transmitted waves are received at rectenna which rectifies, gives DC as the output DC is converted back to AC 4/20/2011 Wireless Power Transmission 8

10. Rectenna “An antenna comprising a mesh of dipoles and diodes for absorbing microwave energy from a transmitter and converting it into electric power.” Microwaves are received with about 85% efficiency. Around 5km across (3.1 miles) 95% of the beam will fall on the rectenna.

11. 5,000 MW Receiving Station (Rectenna). This station is about a mile and a half long in US.

12. Applications

13. Space-based solar power 1968’s idea for Solar Power Satellites proposed by Peter Glaser Would use microwaves to transmit power to Earth from Solar Powered Satellites To efficiently make use of renewable energy i.e., solar energy Solar Powered Satellites are placed in geostationary orbits 4/20/2011 Wireless Power Transmission 12

14. From the Satellite Solar power from the satellite is sent to Earth using a microwave transmitter Received at a “rectenna” located on Earth

15. Possible Designs

17. Advantages over Earth based solar power More intense sunlight In geosynchronous orbit, 36,000 km (22,369 miles) an SPS would be illuminated over 99% of the time No need for costly storage devices for when the sun is not in view Only a few days at spring and fall equinox would the satellite be in shadow

18. Other projects Alaska’21 Grand Bassin Hawaii 4/20/2011 Wireless Power Transmission 17

19. Current Developments

20. SPS 2000

21. Details Project in Development in Japan Goal is to build a low cost demonstration model by 2025 8 Countries along the equator have agreed to be the site of a rectenna

22. Continued 10 MW satellite delivering microwave power Will not be in geosynchronous orbit, instead low orbit 1100 km (683 miles) Much cheaper to put a satellite in low orbit 200 seconds of power on each pass over rectenna

24. Advantages of Wireless energy transfer Efficient Easy Need for grids, substations etc are eliminated Low maintenance cost More effective when the transmitting and receiving points are along a line-of-sight Can reach the places which are remote 4/20/2011 Wireless Power Transmission 23

25. Conclusions More reliable than Traditional power In order for WPT to become a reality it several things have to happen: Government support Cheaper launch prices Involvement of the private sector

26. References S. Sheik Mohammed, K. Ramasamy, T. Shanmuganantham,” Wireless power transmission – a next generation power transmission system”, International Journal of Computer Applications (0975 – 8887) (Volume 1 – No. 13) Peter Vaessen,” Wireless Power Transmission”, Leonardo Energy, September 2009 4/20/2011 Wireless Power Transmission 25

27. Contact: Shubham Jain Email: shubh000007@gmail.com

28. THANK YOU! 4/20/2011 Wireless Power Transmission 27