Report 4 (of 6): Gone With the Wind - Philippines

Introduction

Water pumping is one of the most basic and widespread energy needs in the rural areas of the world. It has been estimated that half the world's population do not have access to clean water supplies. The 1998 El Nino has brought drought with it and although in towns the water supply is still fairly regular, in the country, people are being forced to walk long distances and queue for hours just to fill a few containers with enough water to meet their everyday needs. Sometimes people have to collect water two or three times a day and each time it takes two or three hours. A windpump gives access to excess water and is an affordable technology which can provide the answer to water shortages and droughts.

The Philippine government aims to utilise renewable energy sources to achieve energy self-sufficiency by the year 2005. The Philippines are strategically located on the Asia Pacific monsoon belt which gives the 7,100 islands high potential for utilsing wind energy. The islands lie on the prevailing monsoon and throughout the year there is almost a constant supply of wind. The south west monsoon wind starts in May until late September and the north east monsoon starts early in October until April. The average recorded wind velocity in the Philippines ranges from 1 to 8 metres per second.

Windpump Designs

Windpumps can be produced with minimum skill and labour.In the Philippines, they are manufactured locally using local and imported designs. Most of them are second generation-types (low cost and low start up wind speed)with multiple twisted blades. They can be made from locally available materials.

The windpump is made of 24 or 33 twisted blades and can have a rotor diameter ranging from 1.5 to 7.5 metres. It is equipped with a tail vane that directs the rotor perpendicular to the wind direction and a spring loaded side vane which serves as a safety device for the windpump in case of high wind. The rotor, side vane and tail vane are bolted to the head assembly which is elevated by either a three or four legged lattice tower to a height of 6 to 10 metres depending on the location where the machine is to be installed.

Mechanical windpumps can pump water at a rate of 5 to 160 cubic metres. The latest designs have a start up speed of 1.5 metres per second and will automatically shut off at 7 metres per second.

In the Philippines project, it only takes 36 hours and four men to erect a windpump. The blades start generating energy with windspeeds from 7.5 kilometres per hour. The optimum speed is 25 kilometres per hour. The blades power a shaft which creates energy for the water to be pumped from the water table. The pumps require minimum maintenance.

Wind machines are highly dependent on wind and selection of the type of windpump, model and sizes will depend on the site. The quantity and the depth of the source of water also need to be considered. As with any technology drawing water from the water table, if the area is overpumped, the water table drops and sea water can seep in. The ideal location for a windpump is therefore within close proximity to a river.

Consideration also needs to be given as to whether the windpump is intended for household use where continuous operation is necessary at a lower output, or for agricultural use where large volumes of water are necessary but for shorter periods.

The wind resource potential, the wind velocity, the diameter of the rotor, the volume of the water to be pumped, and the suction and discharge head will all affect the economics of a windpump.

Windpump Irrigation Systems

Agriculture, which is the primary industry of the Philippines, is one of the areas where wind energy utilisation can be addressed. The introduction of high yielding crop varieties and improved cultural practices, intensive production of high value or key crops, introduction of new breeds of animals, establishments of agro-industrial processing plants, and many others, necessitate for alternative sources of energy to meet the water requirement and to supply low-cost electricity.

Wind is a high potential source of energy and if used for irrigation purposes would mean a reduction in the cost of production and therefore, competitiveness in the world market increases.

Windpump for Surface Irrigation System

The windpump is directly coupled with to a small farm reservoir or to a concrete tank for irrigating rice and vegetable crops. Water pumped by the machine is stored in a reservoir or tank to provide the right amount of water needed for land preparation and crop maintenance on time.

Windpump for Pressurised Irrigation System

The windpump is coupled to a header tank where water lifted from the well is stored to operate drip or sprinkler systems. From the tank, a series of drippers can be tapped to the lateral lines to supply water to orchard farms, fruit trees and other crops. Micro-sprinklers can also be used for this system to supply water to cut flowers or nursery seedlings in greenhouses.

Cost

As a natural source of energy, the wind is freely available and produces none of the harmful pollutants associated with other fuels. Unlike coal, oil, and gas, it is constantly renewable and will never run out. Wind energy can also be one of the most economic ways of producing power in small quanitities.

The capital costs for wind machines can vary considerably depending on the performance required from the system which affects the choice of design. The cost of materials and labour, for both manufacturing and installation, and the cost of shipping can also be significant.

In the Philippines project, with capital costs from as little as US$150, the windpump technology is now cheaper than either paying for water or for the electricity needed to pump it from the ground.

Although windpumps can require a relatively high initial capital investment, the total cost over the life of the pumping system is about half of that for a conventional motorised water pumping system

With a relatively small amount of maintenance, wind machines can be expected to have a life span of about 10 to 20 years - double that of motor-driven pumps - and there are no fuel costs over the whole of this period. On the other hand, motorised pump sets require frequent maintenance in the form of oil changes, engine overhauls, replacement parts and checks on wiring etc., all of which need skilled, specialist manpower which might be expensive or simply not available. During the whole lifetime of the motorised pump set, it will be consuming energy in the form of electricity or fossil fuel.

Economics show that mechanical windpumps are highly competitive to electric and diesel fuel pumps in terms of the overall cost of water pumped per cubic metre. This is especially true in areas that are inaccessible to the electric grid and where the transportation of fuel increases running costs of the system.

Advantages of Windpumps

1. Windpumps eliminate the use of imported fossil fuels which are generally expensive. 2. Windpumps have low maintenance costs. 3. Windpumps ensure a year round supply of water, especially during windy periods. 4. Windpumps are environmentally friendly technology - they do not burn fuel. 5. Windpumps can be used for domestic purposes or as irrigation systems and are suitable for rice, vegetables, fruit trees, nurseries, greenhouses, flower gardens, lawns etc. 6. Prices of fuel oil and electricity are increasing, therefore, by using wind energy for pumping water and for supplying electricity, energy related expenses are reduced and consequently products become more competitive in the world market.

For further information, please contact:

Alexis Belonio Wind Energy Association of the Philippines c/o CPU-ANEC, College of Engineering, Central Philippine University, 5000 Iloilo City, The Philippines.

Dan Dorillo, Condor Windpumps, Iloilo City, The Philippines.

Intermediate Technology would like to thank Alexis Belonio, from the Central Philippine University, for his in help in providing the original material on wind energy.

Further reading available from ITDG Development Bookshop

Windpumps for Irrigation H.J.van Dijk and others This book provides readers with sufficient information on windpumps to judge their utility under various circumstances. Besides technical aspects, the authors discuss issues such as collection of climatic data and economic feasibility . TOOL 98pp 1990 œ8.95

Windpumps: A guide for development workers Roy Barlow, Francis Crick, Peter Fraenkel, Anthony Derrick and Varis Bokalders The wind is a renewable energy resource that can never be exhausted, and which avoids pollution, making it one of the most environmentally sound energy options available. This book takes the reader through every aspect of wind energy in a systematic way. ITP ISBN 1 85339 126 3 144pp paperback œ14.95

Water Pumping Devices: A handbook for users and choosers (2nd Edition) Peter Fraenkel Efficient and effective irrigation of the land can have a dramatic effect on the agricultural output and economic well-being of a community, and smallholdings, defined in this book as up to 25 hectares (60 acres), can be the source of a significant proportion of a country's food production. At the heart of effective irrigation lies the problem of lifting or pumping water. This handbook, newly revised and reformatted, surveys the water-lifting technologies that are available and appropriate for smallholdings. It is a detailed and practical review of the options, especially for irrigation but also for other purposes, and the costs and general suitability of the different technologies are examined with the aim of enabling farmers and policy workers to make informed choices. ITP ISBN 1 85339 346 0 224pp paperback 1997 œ19.95

Power from the Wind: A history of windmill technology R. Hills Cambridge University Press ISBN 0 521 56686 X paperback œ19.95

To order any of these books from ITDG Development Bookshop, send a Sterling Cheque (adding 15% for postage and packing to European addresses, 25% elsewhere), or credit card details (American Express, Visa or MasterCard) to:

ITDG Development Bookshop 103-105 Southampton Row, London WC1B 4HH,United Kingdom. Tel + 44 171 436 9761 Fax + 44 171 436 2013 Email orders@itpubs.org.uk or visit our website at www.developmentbookshop.com.

TVE/ Practical Action gratefully acknowledge support for the HANDS ON programmes from the UK's Department for International Development (DFID), the European Commission (EC), the UN Foundation and UNDP/The Equator Initiative in collaboration with the Government of Canada, IDRC, IUCN, BrasilConnects and the Nature Conservancy.