*** Pedal Power Project being developed by AID-India *** The email correspondence below details the evolving design and current challenges of the project. They would like MIT to assist them in refining or redeveloping a low-cost human-powered prototype. Feel free to contact Ravi Kuchimanchi in India and Tarun Jain in Boston for more info. Thinkcycle Challenge posted by Nitin Sawhney , Jan 7th 2001 Note: This challenge is being posted in plain text format, which clearly demonstrates the limitations of current techniques for problem posting and development. Here a Thinkcycle interface seems more appropriate. ----------------------------------------------- Date: Tue, 09 Jan 2001 22:16:25 +0500 From: Ravi & Aravinda To: Tulika A. Narayan , Aniruddha Vaidya , kuki@cheerful.com, michaelm@fnmail.com, JRS , Prasad Subramanian , nitin@media.mit.edu, Sudhakar Adivikolanu , Sudhakar_Adivikolanu@i2.com Subject: update on pedal power generator The pedal power generator has been running steadily since October 2000 in six jeevanshalas and one office in the tribal area of the Narmada Valley, where children take turns pedalling just a few minutes each day to light their rooms for study at night. A recent group of students visiting from Chennai were delighted to go from village to village and find such a sustainable and self-reliant form of light running everywhere. Villagers are saving money that they used to spend on kerosene and battery cells, and getting brighter light as well. It is not by accident that the pedal power generator was pioneered in Domkhedi, tested and improved during Satyagraha 2000 ... just goes to show that where there is sangharsh, there is nirman. Here is a photo of Luvaria bhai of Jalsindhi, first village of MP to face the waters, generating electricity on the pedal power generator. Ravi ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ Association for India's Development research, direct action, advocacy, and fundraising for just, equitable, sustainable development for life and livelihood ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ * ~ vikas chahiye. vinash nahin. | www.aidindia.org ----------------------------------------------- Date: Mon, 21 Feb 2000 17:57:51 -0500 From: Ravi & Aravinda [mailto:aid@vsnl.com] To: aid-boston@egroups.com Subject: [aid-boston] Pedal Power *** Pedal power WORKING! *** You will be happy to know that Association for India's Development (AID) has developed a working prototype of a cute pedal power generator that produces about 35-45 W on pedalling. It's material cost come to about Rs 2500 (add to this battery, tubelight/CFL and assembly) and can be put together at a cycle-shop. 1.5 lakh villages in India are without any electricity supply, and this would be ideal for schools and NFE centres in such villages that meet in the nights or closed class roms even in day time. Children can each pedal 5-10 mins a day (in exercise/sports period) to produce what will light up the class rooms. Currently in many such places a kerosene bottle with a wick is used that has a 1% efficiency in converting energy to light and consequently costs a lot (Rs 6 / litre, 2-4 nights/litre/room) and provides no more than a candle light where children study. A 9-12 W Compact Fluoroscent Lamp (CFL) that provides sufficient light for a class room will work for 2-4 hrs on one hour pedalling. This can also be a good exercise machine for a gym. For village and panchayat meetings. For NGOs and people's movements. Schools, Gyms, movements, NGOs, panchayats and people who want to try this out please contact us for the video/know-how/to order the models. Those who can help further improve this product, please also get in touch with us. -- Ravi, Venkatesh, Aravinda. E-mail: aid@vsnl.com Phone: (022) 5566703 (ravi/aravinda), 8619349 (venkatesh) Address: AID-India, C-7 Banganga Hsg, Govandi Stn Rd, Deonar, Mumbai 400088 ---------------------------------------------- Date: Wed, 23 Aug 2000 12:53:00 -0400 (EDT) From: Ravi & Aravinda [mailto:aid@vsnl.com] CC: Ramanujam Raman To: aid-boston@egroups.com Subject: [aid-boston] Energy Alternatives This was in AID-News today. Chem-E, Mech-E folks - any ideas? Pedal power, micro-hydel etc. We are just back from the Narmada valley for a couple of days and before we get back again thought I'd bring you all up-to- date with the energy related activities in the valley; The pedal power generator is working really well. We are using it for 3-6 hrs of lighting every night since July 15, depending on the work, and the battery has not gone down at all. So this is very good news. (An article titled "Pedal generator makes mockery of Narmada Dam" appeared in India today,and can be found at http://www.india-today.com/ntoday/newsarchives/100/8/16/n4.shtml) A Micro-Hydel generator has also been installed by Anil, Madhu, Chogalal, Champalal and the valley people. It's very interesting and has very broad applications in almost every hilly region. Even when water comes out from the ground/down the hill at the very slow rate of 1 litre in 5 seconds, we collect and store it behind a small check dam 80 cm high and 1 metre broad and in a tank constructed out of cement and reinforced with some iron rods. Thus in a day we collect 18,000 litres of water. This water is dropped 30 metres down a steep slope, at a faster rate of 1-3 litres per second in the night for 3 hrs when power is needed. This rotates a turbine and runs several CFLs. The total installation cost works to about Rs 45,000 per KW. Something for a whole village of 80 households can be as big as 4 KW and needs a trained village person to maintain it. This has such a broad application that it is guaranteed to be useful for any hamlet/village on the hills. Water flowing at such slow rates is easy to find for atleast 6 months of the year. Streams can be made more perinnial using water-shed. So people visiting villages or working with NGOs or movements be on the look out for potential places that could benefit from this design. It needs a lot of village mbilzation and volunteering to make the check dam and lay the pipes etc. So people in village and NGO/movement has to be very enthusiastic. Likewise for pedal power, we will be able to make them available for interested groups/villages. Bright ideas are also needed for nightlamps, torches etc that will save energy. Energy surveys we did indicate that 3 litres of kerosene (Rs 30) are used for lighting purposes by those households that have one kerosene lamp in their house per month. Jeevanshalas (boarding schools) use about 25-30 litres a month. In addition money is spent for batteries of torches -- dry cells cost about Rs 7-9 per cell. The jeevanshalas use about Rs 250 per month on batteries. The other main challenge is a replacement for the 12 V car battery as it is expensive (though very convenient and available everywhere). Whether by pedalling or using wind, we need to store energy in such a battery for use later. Can you think of (or do you know) mechanical gadgets instead that can store energy mechanically and when needed they can then release that energy to turn an alternator or something to make current. Those with suggestions on efficient torches, winding torches, night lights, battery alternatives etc please get back to me. People with some knowledge and interest/experience who can put together technical energy info on web will be useful to us for reference -- for example dos and don'ts on batteries etc. Another big untouched department is that of watering the farms. Even in rainy season there are periods when there may not be rain for 7 days, 10 days or even 15-20 days. In such a dry spell the crops die/weaken. What is reqd is small amounts of water even if once a week per field if there is dry spell in the middle ofrainy season. Water maybe available in a river a few meters down or a well some metres away. People who can think of (or know of) efficient systems for this please get back to me -- this is a different problem than irrigating for cultivation in the off-season. It is great to see that "alternatives" are taking shape in the Narmada valley. It is the struggle against the centralized approaches to developmenbt such as big dams, that is both giving a space for decentralized development ("alternatives") and inspiring people to take them to a competitive level, while the satyagraha is providing the right atmosphere in bringing people together. - Ravi (aid@vsnl.com) ---------------------------------------------------- From: Ravi & Aravinda [mailto:aid@vsnl.com] Sent: Sunday, October 29, 2000 12:36 AM To: Jain, Tarun Cc: 'Dipangkar Dutta (E-mail)'; 'ramkumar@mit.edu'; 'Nitin Sawhney (E-mail)'; Venkatesh Iyer Subject: Pedal Power Challenges Boston can Work on Dear Tarun, Let me know if Ronnie Bhai emailed you. Otherwise just wait a few days. Sometimes he is on tours and takes time to reply. But basically here are some ofthe design details: We have two postures or two types of models -- one is cycle type and other is reclining chair type. The former seems more in demand in the villages. For the cycle model we basicallyuse the frame of a cycle that we buy from cycle shop without the wheels or mud-guard surrounding the wheels. We use the same cycle chain but instead of driving the back wheel this drives another chain so that we have a good overall speedup ratio from 30-40 RPM or so of pedalling to about 1400 RPM that the generator rotates. The second chain is connected to a generator that has permanent magnets. We could increase the speed ratio more but we have adjusted it for the generator we have and if it is more than this we have a much lower RPM of pedalling that generates the same voltage and then it becomes more strenuous onthe person pedalling. If we decrease the gear ratio much more then wee need much higher speeds of pedalling. The generator generates about 13 -13.5 V at 1400 RPM or so while charging a 12 V tubular battery, and the currents we get are from 2 - 4 A easily for normal pedalling that one can sustain. Of couse pedalling much faster can give even 4-8 A currente but one cant sustain this very long. Some design suggestions you can make are on generators of even lower RPMs maybe. (we started with having a generator of 2800 RPM and then we had to pedal at almost 70 RPM that was hard and we had slightly more speed-up ratio through gears than the current one but in our latest models we have changed the generator so that its rated features are at 1400 or so RPM). We are using usually a 40 AH battery for storing the energy though a 24 AH is also possible. 40 AH is normally charged using 13.5 V and max of 5 A current. The 24 AH is normally charged using 13.5 V and 3 A max current. You can also work on some add-ons which we have not concentrated on working -- for example charging 6 V batteries either using the 12 V charged battery for this or directly charging from PPG. Now 6 V batteries are usually charged with much lower currents as they are usually found in rechargable torchlights village people buy to charge using solar panels (charging current is usually not more than Amp Hr of battery divided by 8 though if you have better ways of estimating this let me know). batteries usually go bad if they are charged by much higher currents than they can handle. We do not have any fly-wheels and that maybe something you can experiment on. Basically due to low pedalling speeds there isnt much inertia in the system and the current fluctuates a lot in every cycle of pedalling. We dont really care about this as the battery can take such fluctutations while charging but maybe a fly-wheel will give a more even feel onthe person pedalling. Flywheel is something we didnt experiment on at all. The cost ofmaking is quite minimum as weuse all standard parts available in market -- cycle frame, chain, and the smaller chain is also available in markets etc. Wejust weld some rods and stands to this frame so it stands on its own. The motor we get from some electric guy who sends them. We also tried the car alternator instead of a permanent magnet generator butthat somehow wasnt as efficient. Photos we will scan and send you when we get them ofthe cycle posture. The reclining posuture photos you must have seen on aid web page -- projects section -- iluustrated projects on sustainable energy -- pedal power page -- pedal power photos. Venkatesh now in Delaware can also help you as we all worked together while he was in India. We use the charged battery to light up CFLs -- 11 W -- using a 12 V choke system that we purchase. This solves the problem of lights from 7 Pm -- 11 Pm or so in the villages. However usually in many houses in villages the kerosene flame is reduced and kept running through out the night as a night lamp. Now we thought of using LEDs for that since 11 W CFLs burning through out the night is a lot of pedalling. We got some LEDs from AID friends when they came to India and they seem tobe decent. However we have a very limited supply and cant experiment. You can do that there and it could then be useful. Basically our power system should address: 1. lighting needs from 7-11 PM (which it is doing well) 2. Torch light and radio etc needs that use lower voltage batteries (which we currently are not charging). 3. Night light needs. (LEDs seem to bethe answer for this). We installed the PPGs we took that day in the jeevanshalas. Kids love them. The cycle type is a big hit with everyone wanting that. The reclining type was a bit hard for most kids owingtotheir legs not reaching properly so we put that more where there are activists who can easily do both. Lots of interest from villagers who wantto buy too. But our mood was cut short when the Supreme Court decidion came and we had to leave things and rush to Badwani. But anyway miost of the PPGs have been personally installed by Aravinda and me and a few we gave explicit instructions to some NBA activists who have now enough experience with them to do so. I sent the old PPGs generator to NBA office in Baroda via Shripad. Please pick it up from him or call the NBA office and Sukumar or Shripad will have it sent to you. Do visit www.ecoZen.com to about other things we are pursuing. I have not really prepared any good looking drawings for this. We made some sketches and a sample and some jigs and fixtures and then keep replicating. I can make drawings but need time. Why not study a sample or photos and make suggestions. Some of the suggestions can be tried out at my place also. I have certain restrains regarding design changes. There are parts which cannot be economically produced in small quantities. So I have used some bought out things and kept some items common with our electric bike design. That way things are more under control. If you look at price break-up you see that very small proportion of cost is in the parts that are made only for the PPG. The efficiency of the drive system is already very high. I cannot really measure it I can promise it is over 95 %. The efficiency of the generator is the only "Improvable" place. And as per my supplier, very expensive and high tech to do so. The next step can only be a direct drive high torque hub without gears and chains. I believe that this can be reveres engineered from a time proven model I am keen to do this for my electric bike also. But this project in my present circumstances seems a bit into the future. -- Ravi ------------------------- From: Aravinda &/or Ravi [mailto:aid@vsnl.com] Sent: Sunday, January 07, 2001 5:04 AM To: Jain, Tarun Subject: Bostons pedal power It will really help if we can get started fast. One thing you can do is to purchase an appropriate generator. it costs about $500. This will just be the bare-bones generator with gears and a pedal attached but you have to connect this to a bicycle frame or build some seating arrangement around it. What willhelp us if if you can first do some tests on the generator -- like charge a 12 V battery by rotating it in some fixed speeds and plot the voltage and current versus RPM curves for it. We will compare this with the generator we have in India and see if we can improve based on what you have. Simultaneously it would be good to ask the university for anothe $500 or $1000 once you ahve these results for building the rest of the frame. I will hep you with this proposal. It wouldbe ideal if the Boston group gets to work fast on this as it willhelp the R & D in India and your work can then contribuite to the product we make here. Please forward this to others in the Boston group so that they know what they can purchase in the USA to start work on building a pedal power system there. They can go through this and order the generator with chain and pedals -- bare bones one -- thats advertised for some $497. http://www.windstreampower.com/ Ravi