A Sustainable Alternative To Wind Electric Rev B

Energy and Sustainability March 2009

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem March, 2009 Supervisors: Gunilla Britse, Ola Eriksson, Fan Zou Examiner: Liselotte Aldén Gotland University, Visby, Sweden

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Cover Photo: Windmills at American Wind Power Center, Lubbock, Texas Cover Photo Source: http://www.southplainscollege.edu/ppress/issue_2_05/spotlight/spotlight_2_05.htm

Executive Summary

The need to offset greenhouse gas emission has exploded in the number of opportunities to provide renewable energy systems to developing areas around the world. Large and small-scale wind electric systems are being installed in these developing areas on an increasing level. Unfortunately, the local people may not have the skills or capability to install, operate or maintain the sophisticated wind-electric systems that the industrialized nations are providing. This paper attempts to offer an alternative to the sophisticated systems presently used by suggesting that we step back and consider the capabilities of the local people when we offer a wind power alternative. This paper will suggest a wind power solution that is easy to install, operate, maintain, and still serve the same purpose as the latest wind-electric systems. This paper will outline the capabilities of a wind power solution using compressed air instead of electricity as the energy source.

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Table of Contents Cover Photo: Windmills at American Wind Power Center, Lubbock, Texas ........ 2 Executive Summary ............................................................................................................ 2 Table of Contents................................................................................................................ 3 Introduction......................................................................................................................... 4 Wind Power – A Brief History ........................................................................................... 5 Figure 1 - Typical Water Pumping Windmill ......................................................... 6 Figure 2 - Halladay Windmill from 1850's ............................................................. 6 Over-Reaction to a Simple Problem ................................................................................... 7 A Simple Answer................................................................................................................ 8 Figure 3 - Single Purpose Windmills for Water Pumping or Grain Grinding ........ 8 Figure 4 - KIJITO Wind Air Lift Pump.................................................................. 9 Figure 5 - BowJon Turbine ..................................................................................... 9 Figure 6 - Airlift Technologies Windmill............................................................. 10 Figure 7 - Koenders Windmill .............................................................................. 10 Figure 8 - Average Windspeeds (m/s) for Select African Countries .................... 12 Figure 9 - Example of an Air Storage Tank.......................................................... 14 Figure 10 - Air Operated Impact Wrench ............................................................. 15 Figure 11 - Air Operated Hammer Impact............................................................ 15 Figure 12 - Air Operated Drill .............................................................................. 16 Figure 13 - Air Operated Pistol Grip Drill............................................................ 16 Figure 14- Air Caulking Gun................................................................................ 16 Figure 15 - Air Shears........................................................................................... 16 Figure 16 - Air Operated Vortex Tube Devices for Heating or Cooling .............. 17 Discussion ......................................................................................................................... 18 Conclusion ........................................................................................................................ 19 References......................................................................................................................... 20 Informational Websites..................................................................................................... 21 Endnotes............................................................................................................................ 21

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Introduction In many areas of the world, there is no local energy supplier, no electricity, no electric utilities, no power lines and no reasonably foreseeable electric connection to the rest of the world. How can this be? How can we as a people have ignored this for so long? Now that the industrialized countries of the world have recognized that, our climate is changing. Changing for the worse, partially because of our use of fossil fuels to create our electricity. How can we stop the newly developing areas of the world from adding to the chaos and forthcoming disaster? Experts from the European Union (EU) met and debated how they can reduce the greenhouse gases that are threatening the world. The EU has formulated an Emissions Trading System (ETS) that allows member countries to offset their current emissions of greenhouse gases by providing for non-polluting, renewable and sustainable energy projects in developing countries. The intent of this paper is to suggest and advocate for a change in how renewables, specifically windpower is being used. While the use of windpower is applicable in many developing nations, on developing nations is not widespread and this paper will use mostly data from sub-Saharan Africa since more data is available. This is not to suggest that the change advocated cannot be applied elsewhere as well. High poverty levels especially in rural areas are a significant challenge that faces East Africa. Based on the national poverty threshold, the number of people living in poverty in Kenya is estimated to have risen from 11 million (48% of the population) in 1990 to 17 million (56% of the population) in 2001. Most poor households (87%) live in rural areas. Of these, subsistence farmers account for over 50% in Kenya. Efforts to reverse poverty trends have been inadequate, as poverty levels continue to rise. In Tanzania, surveys indicate that poverty is more prevalent in rural areas relative to urban areas. About 60% of rural population is poor compared to about 39% of the urban population.a Many of these projects involve the use of wind electric turbines that are installed to offset the use of diesel generators for making electricity. These installations rely heavily on foreign expertise, as the developing country usually does not have the expertise to install or maintain such modern systems. Many of today’s turbines involve the use of computerized supervisory control and data acquisition (SCADA) systems. How can a developing area that may be poorly educated provide for such systems? Usually they do not and the area becomes dependent on outsiders. The cycle of poverty and education are not broken. How can the world assist these developing countries and still use a renewable and sustainable resource such as wind?

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Renewable energy technologies (RETs) can play an important role in poverty reduction in rural areas in the region. The Energy, Environment and Development Network for Africa (AFREPREN/FWD) reports that this is especially true for RETs that operate on the basis of solar, thermal, mechanical and animate power, i.e. non-electrical RETs. This paper will focus on the positive aspects of wind power for developing areas but not by using wind electric with all of its sophistication and modern technology. Good, oldfashioned wind power, a non-electrical RET, but using modern technology and producing an ancient energy source – air. This technology is easy and safer to install, operate, and maintain for a simple, developing culture.

Wind Power – A Brief History Wind has been harnessed to lift water for more than 2000 years, first in China and the Middle East, and spreading to Europe. The energy in moving air, wind, can be converted to either mechanical or electrical energy. Recently, use of wind energy to generate power has been given more attention than ever before. With wind pumps, moving air turns a "rotor", and the rotational motion of the blades is transferred to harmonic motion of the shaft, which is used to pump water or drive other mechanical devices such as grain mills. Depending on the terrain, some types of modern wind pumps generate electrical energy to drive pumps. Water from wells as deep as 400 meters can be pumped to the surface by wind pumps.b 2009 marks the 155th anniversary of the wind pump in America. At one time, there were over 100,000 water-pumping windmills in the United States. In Africa, there only a few thousand windmills installed for water pumping and less than that for electrical generations. Windmills generally consist of two types, with the classification depending on the orientation of the axis of rotation of the rotor. Vertical-axis wind turbines are efficient and can obtain power from wind blowing in any direction, whereas horizontal axis devices must be oriented facing the wind to extract power. Most windmills for waterpumping applications are of the horizontal-axis variety, and have multi-bladed rotors that can supply the high torque required to initiate operation of a mechanical pump. Windmills can also be used to generate electricity, but electricity-generating units usually consist of vertical-axis rotors or high-speed propeller rotors, due to the requirement for Low starting torques. The following sketch illustrates a typical water-pumping windmill.

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Figure 1 - Typical Water Pumping Windmill Source: WIND-POWERED WATER PUMPING SYSTEMS FOR LIVESTOCK WATERING, Agriculture and Agri-Food Canada, 2009

Figure 2 - Halladay Windmill from 1850's Source: http://www.ironmanwindmill.com/windmill%20history.htm accessed on March 14, 2009 A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Over-Reaction to a Simple Problem While the industrialized countries of the world are developing larger and more sophisticated wind turbines to produce electricity, this is just adding to the problems of a developing area. With all good intentions, modern small and large-scale wind electric systems are being installed as part of relief and other programs to aid these areas. The problems that the author sees with this is that the grateful recipients are not adequately educated or trained in the installation, operation and maintenance of these sophisticated systems. Despite training the communities on wind pump installations and maintenance, pumps in remote areas have not been maintained to the required standards since the trained technicians either leave the area to seek employment elsewhere or are technically incapacitated to carry out their work effectively (Harries, 2002). Technicians and buyers are often unfamiliar with wind pump technology, and pumps in remote locations often break down because of a lack of servicing, spare parts, or trained work force. Pumps installed by churches, not for profit groups and government are more affected due to lack of community involvement and ownership and often wait for the installing group to come back and fix any mechanical problems.c Whether the wind electric system produces DC or AC power, 12 volts or 600 volts, the recipients are not used to electric power and are not able to properly support their multiyear life expectancy. While there are no figures or study data on the following, the author sees that these systems whether they are wind electric or photovoltaic or a hybrid are often left to rot or waste away if the installation has any failures. To the author, this is a common sense response to a nomadic way of life, if it does not work and you cannot fix it; then you leave it. Can this attitude and culture of indifference be overcome? Yes, with many years of learning and adaptation as this is how the rest of the world evolved. If you follow the history of electricity you will see that for the first 100 years of its known existence, electricity was the subject of experimentation and failures. Once a successful experiment brought useful items like lights and motors, the public’s use of electricity took off on its meteoric climb. Technologies and innovations came and went. Thomas Edison originally proposed the use of direct current (DC) for the consumer to use while Nikola Tesla promoted the use of alternating current (AC). Tesla won out with AC current with George Westinghouse’s assistance but this change in technology left a lot of Edison’s equipment to waste away.

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Today, the need to reduce our energy use is coming to the abandonment of the incandescent light bulb in favor of the more energy efficient compact fluorescent but this may still yield to the newcomer, the light emitting diode (LED). As improvements are made, the past or the failures are abandoned. So too will this happen as the indigent peoples who are not capable of repairing their sophisticated equipment abandon it. What these developing areas need is power but do they really need modern electricity? The answer is two-fold. Yes, they need useful power to get things done and in some cases, they need electricity. I am suggesting that everyone step back and consider providing a simpler method of using the wind but incorporate modern advances in to its use. The use of a wind turbine that produces compressed air is my answer to the needs of the developing areas of the world.

A Simple Answer The technology to use wind to pump water, grind grain or to do other useful tasks has been around for centuries. I am advocating that we take the efforts of modern wind turbine design but rather than use it for a single purpose, adapt it to use if form multiple purposes. I am recommending that the windmill be adapted to power an air compressor rather than an electric generator to create a more useful and safe energy supply that a developing culture can more easily use and maintain.

Figure 3 - Single Purpose Windmills for Water Pumping or Grain Grinding Source: http://www.freefoto.com/images/1450/02/1450_02_14---Windmills--Kinderdijk-Kinderdyke-Holland-The-Netherlands_web.jpg accessed on March 14, 2009

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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The change from an alternator or generator to an air compressor has been successfully done for years from manufacturers like BowJon, Airlift Technologies, Koender Windmills and Harries Manufacturing. The most commonly used wind pumps in East Africa region are of the Kijito type (see figure 3), manufactured by Bob Harries Engineering Ltd (BHEL) in Thika and come in a range 8 – 26 feet of rotor diameters.

Figure 4 - KIJITO Wind Air Lift Pump Source: http://www.afrepren.org/images/gallery/Renewable%20Energy%20Kijito%20Wind%20Pump.jpg Accessed on March 14, 2009

Figure 5 - BowJon Turbine Source: http://www.cisolar.com/CatWindPump.htm accessed on March 14, 2009

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Figure 6 - Airlift Technologies Windmill Source: http://www.airliftech.com/specs.htm accessed on March 14, 2009

Figure 7 - Koenders Windmill Source: http://www.koenderswindmills.com/ accessed on March 14, 2009

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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So, how would this non-electric wind turbine work? Quite easily as air compressor technology has been around for a long time. There are several kinds of air compressors--reciprocating, screw, centrifugal. The current airlift wind turbines use a reciprocating piston compressor. It has a piston moving back and forth in a cylinder to compress the air. The turbine blades turn the shaft that move the piston up and down in the cylinder compressing air and releasing it to the system. This one piston assembly is called a stage or in this case a single-stage unit. d The cheapest compressors are single-stage units--they have one piston and cylinder. The air from the atmosphere is sucked into the assembly, compressed then sent to the tank. Next come two-stage compressors, which have a low-pressure stage and a high-pressure stage. The air from the first stage is compressed again by the second stage, which gives more pressure with less stress on the unit. It is easier on the compressor to take air from 2 atmospheres to 4 than it is to go from 1 atmosphere to 4. Most of the air tools being considered for use are powered by air pressures from 1 psi like the Di Pietro motor to 90 psi. For the most part a two-stage air compressor can be used to power most air tools. The compressed air is stored in a reservoir sized according to how much compressed air one would likely need. Air compressors are uniformly measured by the amount of cubic feet of air produced, or Standard CFM (SCFM). SCFM is defined as the measured flow of free air and converted to a standard set of reference conditions (14.5 PSIA, 68 Degrees F, and 0% relative humidity).e The table below is adapted from the Jenny Compressor Company (www.jennycompressor.com) and lists the air volumes needed for various air tools. Air Tool Description Angle Disc Grinder - 7" Brad Nailer Chisel/Hammer Cut-Off Tool Drill, Reversible or Straight-Line Dual Sander Framing Nailer Grease Gun Hydraulic Riveter Impact Wrench - 3/8" Orbital Sander Ratchet - 1/4" Ratchet - 3/8" Rotational Sander Shears Speed Saw

Average CFM @ 90 PSI 5-8 0.3 3-11 4-10 3-6 11-13 2.2 4 4 2.5-3.5 6-9 2.5-3.5 4.5-5 8-12.5 8-16 5

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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The Jenny Compressor Company suggests that you add 30% to the average CFM to obtain the needed CFM. Therefore, if you needed to run an air grease gun 2 hours per day, you would need 4 CFM or approx 1248 cubic feet of compressed air at 90 PSI. (2 x 60 minutes x 4CFM + 30%). How much energy can one obtain from a windpowered air compressor? I will use data taken from Airlift Technologies specificationsf. The Airlift turbine with a 10-foot diameter rotor produces 10 to 15 cubic feet of compressed air per second (CFS) in a 10-12 mile per hour wind. The simple conversion to meters per second from miles per hour is 1 mph = 0.45 m/s; so 12 mph is equal to 5.4 m/s. Fifteen CFS amounts to 900 cubic feet of compressed air per minute. Remember the air grease gun that need 1248 CF of compressed air, or roughly two minutes worth of wind produced compressed air to run the device for two hours. Comparing the windspeed needed to produce 15 cubic feet of air per second (cf /s) at (5.4 m/s); you can see from the table below that this windspeed is available in at least a quarter of the African countries studied. For this example, we will use an estimated output of 10 cf/s to reflect a windspeed of approximately 5 m/s that reflects about ½ of the countries.

Figure 8 - Average Windspeeds (m/s) for Select African Countries Source: Karekezi, S. and Ranja, T. (1997). Renewable Energy Technologies in Africa. London, Zed Books A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Ideally, one should consider at least one year’s worth of detailed meteorological data in conjunction with the wind turbine’s specifications to determine expected energy yield. However, for a rough estimate the average over a year can be estimated by using the following formula: P = 0.5 * AV3 x 8765 hours Where P = average power output in watts (W) And V = yearly average wind speed in meters per second (m/s) at rotor height. And A= area which is pi x radius squared Using two different diameters for this example, a 3-meter (roughly 10 feet) and 5 meters (roughly 15 feet) to represent the current available air lift turbines; For the 3-meter diameter turbine (1.5 meter radius) P = 0.1 * (1.5 * 1.5 * 3.14159) * 53 * 8,765 hours / year P= 0.1 (7.0685) * 125 * 8,765 /1000 = kWh/y P= 0.1 * 7.0685 * 1095.625 = 774 kilowatt-hours / year For the 5-meter diameter turbine (2.5 meter radius) P = 0.1 * ( 2.5* 2.5 * 3.14159) * 53 * 8,765 hours / year P= 0.1 (19.635) * 125 * 8,765 /1000 = kWh/y P= 0.1 * 19.635 * 1095.625 = 2,152.25 kilowatt-hours / year We obtain an average power yield per year at 5 m/s of between 774 to 2,152.25 kilowatt hours per year. To convert this to horsepower, you would use the conversion 1 kilowatt = 1.34 horsepower. The air lift turbines could produce between 1,037 to 2,883.95 horsepower per year or roughly 8 horsepower per day. Since most loads would not be run 24 hours per day, the 8 horsepower could be compared to running a 1 horsepower motor for roughly 8 hours or a ½ horsepower motor for 16 hours, etc. This rough calculation does not figure efficiency losses but is intended to illustrate that a small 5meter air lift turbine can provide useful energy where there was none before. At the 10 cfs output of the compressor the 5-meter air lift could produce roughly 4,800 cf of compressed air, enough to run an air-powered speed saw (5 cfm) for over 15 hours per day. If the turbine rotor diameter doubled, you would obtain eight times as much energy (the law of the cube) so a 10-meter turbine could provide roughly 2.5 horsepower per hour. A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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How does producing this much energy make it safer, easier and better for a person in a developing area? First off, the turbine installation does not require a lot of effort for siting when compared to a wind electric system that needs to capture as much energy as possible from the wind. The tower for an air lift turbine can be lower to the ground thus lowering installation and repair efforts. The most significant aspect is that the individual is dealing with compressed air and not electricity. There would be no batteries, inverters or other electronic controls that are dangerous to the inexperienced and untrained. With air, the main concept is to keep the compressed air contained. The main training effort would be to check for and eliminate air leaks. Wait a minute, hold on you say. What can an individual do with compressed? Compressed air lines can be easily run as there is no polarity to watch for and nor is there a need to be concerned for shorts or connections to ground. An airline can be rigid pipe or flexible plastic tubing. What about storage? Compressed is easily and safely stored in rubber, steel or other cylinders. Again, the worst that could happen is the air leaks out or the cylinder bursts. There are no chances of electrocutions or electrical fires. Storage tanks are currently readily available in all shapes and sizes.

Figure 9 - Example of an Air Storage Tank However, you ask, “What can I run with compressed air?” All kinds of things can be run with low-pressure compressed air. Below I have compiled a few tools that are currently run by compressed air. I envision that a whole series of household appliances can be adapter from these tools for household use. Picture the air drill below being converted to a household mixer/blender. All of these devices can be used in a home or business.

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Figure 10 - Air Operated Impact Wrench

Figure 11 - Air Operated Hammer Impact

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Figure 12 - Air Operated Drill

Figure 13 - Air Operated Pistol Grip Drill

Figure 14- Air Caulking Gun

Figure 15 - Air Shears Source for figures 10-15: http://www.mountaintool.com.tw/ accessed on March 14, 2009

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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The use of compressed air is safer, easier to install and maintain and to understand for a developing area. Many currently available air tools can be used as-is or converted into household appliances. Wait, what about driving motors or producing the electricity needed for those appliances that cannot be run from compressed air. In 2004, an inventor named Angelo Di Pietro perfected a rotary piston engine. The significance of this engine is that it runs on compressed air. Di Pietro has adapted a golf cart to run off his engine using only 1 PSI of pressure and this cart can run for about 16 kilometers on a 100-liter cylinder of compressed air.g Di Pietro has adapted carts, scooters and a boat to run off his compressed air motor. Therefore, if there is a need to drive a motor of any kind, be it an electrical generator or a lathe, the Di Pietro rotary piston air motor is a possibility. The last aspect of a complete non-electric compressed air system would be to provide heating and cooling using compressed air. For many years, an interesting air technology has been used to provide either heating or cooling from compressed air. This technology is based on the vortex tube invented in 1930 by a Frenchman Georges Ranque.h There are many companies around the world making vortex tube heating or cooling devices. Compressed air is injected into a vortex tube that creates a mini-tornado within the tube separating the compressed air into two streams – one hot and one cold. Compressed air coming into the vortex tube at 70 degrees Fahrenheit ( 21 degrees Celsius) comes out either as super cold air at -30 degrees Fahrenheit (-34 degrees Celsius) or as heated air at 170 degrees Fahrenheit (76 degrees Celsius). So appliances can be made to heat or cool rooms, food, or people using the vortex tube technology and compressed air. Below are pictures of various vortex tube devices.

Figure 16 - Air Operated Vortex Tube Devices for Heating or Cooling Source: http://www.newmantools.com/vortex.htm accessed on March 14, 2009

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Discussion This paper has outlined how a windpowered air compressor can be used to convert the energy in the wind into useful energy. Useful energy that can be used for tools and for heating or cooling. Current airlift wind pumps exist that can power air tools and other air motors that would be useful in developing areas. The use of a low drag turbine such as outlined in this paper are easier to install as they do not need to be installed as high as possible. Their basic design allows the turbine to be installed at most any location. While a properly sited turbine will always perform better, the windpower air compressor is designed for a harsher environment. The turbines do not have complicated electronic controls or features that some wind electric systems. This style of wind turbine has been actively produced for over a hundred years and some of those turbines are still around and working. Durability and long-life is a feature of the modern turbine that produces compressed air. Air compressor have also been around for almost as long a period and are designed for long-life and harsh environments. The use of compressed air at low pressures is safer than electricity. It is safer because it does not involve batteries that could explode, sophisticated control devices that need adjustment or repair, invertors or other charge controllers that may need adjustment or repair. If the compressed air tank leaks, find the leak and seal it. This is a fairly straightforward and easy to understand. The repair parts are not complicated electronic parts; they are plumbers tape or a wrench to tighten a loose fitting. The technology to transfer compressed air from one spot to another for use is again, straightforward and simple to install, operate and maintain. The technology is a pipe or piece of tubing rated sufficiently to handle the sir pressure involved. These turbines do not use high-pressure air. Recall the Di Pietro air motor that uses 1 psi of air pressure. A good garden hose or air hose is sufficient to handle this pressure. Is there a danger of electrocution or fire from using compressed air – No. The worst problem that could occur is that you lose your air. Rather than have the local people worry if they had the correct cables wired and sized properly, you would have a single airline with a valve that turns the air on or off when needed. Again, to fix a leaking airline requires tape or tightening not an electrical engineering degree. Would the parts be available to a local area in the future? It is my belief that the use of windpowered compressed air technology is simpler and cheaper to use when compared to a wind electric system of any size. Air hoses, clamps and tape will suffice with compressed air while a battery, tape, proper wire in the correct size, disconnects and fuses may be hard to acquire in developing areas. Compressed air is a simpler technology – easy and safer to use, easier to understand and operate, easier and safer to maintain. A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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Conclusion The use of wind power to assist developing areas around the world is essential to the future of both the developing area and to the world at large. The use of wind electric systems in developing areas is an example of over reaction of an industrialized world to solve the problems of the lesser fortunate. This paper addressed the difficulty in siting wind electric systems, the complex systems using advance electronics and technology which the developing areas are not yet capable of installing, operating or maintaining. This paper outlined an old technology with a modern twist – the use of non-electric windpower to produce compressed air. The use of compresses air has been around for over a hundred years and can provide the same or better comforts and basic needs for a developing area with a safer, easier to install, operate and maintain technology. Modern windmills are available to produce compressed air that can be used to heat, cool, and even to fuel our vehicles. Compressed air is safer than electricity and easier to understand. The answer for our developing areas is indeed blowing in the wind and by capturing the wind and using it in the form of compressed air, we are providing a zero emission, sustainable, renewable resource to the world.

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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References Balla, P. (2004). Potential Contribution of Non-Electrical Renewable Energy Technologies (RETs) in Poverty reduction in Kenya. AFREPREN/FWD Secretariat, Nairobi. Harries, M. (2002). ‘Disseminating Wind Pumps in Rural Kenya – Meeting Rural Water Needs Using Locally Manufactured Wind Pumps’, Energy Policy, Vol. 30 Numbers 11-12. Special Issue – Africa: Improving Modern Energy Services for the Poor. Oxford, United Kingdom: Elsevier Ltd Harries, M. and Pallister, T. (1999). ‘Kijito Wind Pumps – A Trademark Developed from a Farming Background’, Solarnet Vol.1, No.1 January – April 1999. P14-16. Nairobi, Solar Energy Network IGAD (2004). ‘IGAD Energy Profiles: International comparisons of pumps found in the international markets’. Accessed on March 14, 2009 http://igadrhep.energyprojects.net/ ITDG (2004). ‘Wind Pumping: Technical Brief’, www.itdg.org/html/technical_enquiries/docs/windpumps.pdf accessed on March 14, 2009. Intermediate Technology Development Group (ITDG)

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Informational Websites http://www.windmills.net/ http://www.malibuwater.com/Windmills.html http://www.windmill.com/ http://www.ironmanwindmill.com/ http://www.afrepren.org/about.htm - Energy, Environment and Development Network for Africa (AFREPREN/FWD) http://igadrhep.energyprojects.net/ - IGAD (Intergovernmental Authority on Development) is a regional development organization in Eastern Africa. http://www.ca.uky.edu/wkrec/AirliftPumps.pdf http://www.airliftech.com/airlift1.pdf - air lift windmill http://www.mountaintool.com.tw/ - air tools http://www.engineair.com.au/index.htm - rotary piston air motor http://www.newmantools.com/vortex.htm#vortex - vortex tube technology for heating or cooling

Endnotes a

“The Potential Contribution of Non-Electrical Renewable Energy Technologies (RETs) to Poverty Reduction in East Africa”, 2005, Energy, Environment and Development Network for Africa (AFREPREN/FWD) b http://www.ironmanwindmill.com/windmill%20history.htm accessed on March 14, 2009 c “The Potential Contriution of Non-Electrical Renewable Energy Technologies (RETs) to Poverty Reduction in East Africa”, 2005, Energy, Environment and Development Network for Africa (AFREPREN/FWD) d http://www.ehow.com/how-does_4610510_air-compressor-work.html, accessed on March 20, 2009 e http://www.jennycompressor.com/howtochoose.html, accessed on March 20, 2009 f http://www.airliftech.com/airlift1.pdf accessed on March 14, 2009

g

“Green Buggy Runs on Hot Air” from http://www.rexresearch.com/pietro/pietro.htm, accessed on March 14, 2009 h

http://www.newmantools.com/vortex.htm#vortex accessed on March 14, 2009

A Sustainable, Safer, Easier Alternative to Wind Electric Matt Overeem, Gotland University March 2009

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