In my last blog I mentioned that given the increasing fuel prices, the solar powered rope pump could be set to become highly competitive. The target market of the rope pump would include those with longer financial horizons such as NGOs and other large community institutions, as well as those organisations with a specific interest in low-carbon development such as SolarAid. With the pressure to meet international carbon reduction targets there could be other more commercial avenues too.

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A section from a Ting Ting painting, by a Tanzanian artist, showing the use of a solar rope pump in the 'Solar village'

Back in the UK
I've now returned to Bristol to complete the final year of my masters degree in Mechanical Engineering. Comprehensive system specification and engineering drawings of the solar powered rope pump will be produced during the summer.

As mentioned in my last blog, from September the findings from my study will be used by a student from Mzuzu University in Malawi; who is yet to be selected.

The student will then be responsible for:
• Sourcing all the parts
• Constructing the pump
• Fully testing the system
• Adding any improvements as appropriate
• Carrying out a comprehensive comparative cost-benefit analysis of the pump and its competition.

The final design should then be ready for manufacture and installation by April 2010!

Plans for the future

This project has inspired me to formulate a clearer career path in a field that I was already committed to. I now plan to pursue the development and dissemination of the rope pump technology more generally.

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Me back at Bristol

After graduation (and paying off some debt!) I plan to visit Nicaragua, where I will learn Spanish and hope to learn as much as I can from a Nicaraguan rope pump business, which has been providing 25% of the country's water over the last 15 years.

In the longer term, I hope to set up a rope pump business. Based in Africa, I imagine it's market would be NGOs, the government, private small-holdings, farmers and families. I hope the business model I employ would allow the business to be managed locally within a couple of years, helping to boost local economy.

With the help of good business and some investment, over the coming years the rope pump is set to help many thousands of people to lift themselves out of poverty in Malawi as well as across Africa.

Thank you for reading about the rope pump developments and for following the project!

Due to time constraints and longer than expected lead times it became obvious that it wouldn't be possible to test the system as comprehensively as first intended. Nor would it be possible to get the pump ready to be installed and used as originally intended. Therefore priority was given to gathering vital information and also to finding future support for the project.

A month was spent constructing, testing and demonstrating the solar-powered rope pump on a borehole at Mzuzu University.

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Children help with testing the example rope pump, near Mzuzu University

It was agreed with Maxon, Head of the Teaching Centre for Renewable Energy Technologies Department (TCRET) at Mzuzu University and SolarAid's Milawi Trustee, that a student would take on the project as part of their fourth and final year at the University. The pump was then demonstrated to the whole year to unanimous interest!

The temporary pump installed at the University was intended to be a proof of concept and a demonstration for TCRET to gain support for future local development.

The brief test of the example pump drew 0.14 litres per second from a 15 metre depth and was powered by an 80watt PV panel, capable of running for 6 hours per day. The pump could therefore produce 3000 litres of water per day!

A large amount of further investigation is needed (especially in sourcing the motor) but a very provisional cost breakdown is: pump - $100, motor - $200, PV - $500, totalling $800. At this prices the pump at over double that of a small diesel pump but significantly less than any other comparable solar pump. However, if fuel prices over several years are considered, the solar rope pump looks to be highly competitive.

Please support our work in the development of the rope pump. Help SolarAid to reach thousands of people in Malawi and beyond, to have access to a resource we take so much for granted...water. Thank you.

More from me again soon,

a summary...

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Now I'm back in the UK I have had time to right up a summary of the project for the blog.

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Local children help me test the example solar powered rope pump, near Mzuzu University.

The solar powered rope pump project breaks down into three main phases...

The first three weeks were spent researching the appropriate balance between pump capacity and cost.

Firstly I visited Pump Aid, an NGO which has been successfully installing hand-powered rope pumps in Zimbabwe for 10 years and has recently moved into Malawi to continue its work. The visit provided invaluable information on manufacturing techniques.

I collected information on local water requirements from the Ministry of Water and Irrigation, the Water Resources Board, Water Aid's Malawi office, the Department for Agriculture and the University of Mzuzu. It was decided that a pump capable of delivering between 3000 and 10,000 litres of water a day would be the most appropriate balance between pump cost and capacity. This specification would also position the pump in the market gap between hand-operated and larger automated pumps powered by diesel or photovoltaic (PV) panels.


The next month was spent sourcing materials and assessing local resources, hardware suppliers, manufacturing capabilities and then shipping any parts not locally available. This is probably the period of the project that I personally learnt the most from; an invaluable experience giving me knowledge otherwise unobtainable and essential for any work in the field of development engineering.

The kids pictured above couldn't afford to go to school so they used to hang out with me while I was working on the pump. As you can see, they were intrigued by its capabilities!

I'll be summarising the final stage- testing- in my next blog posting soon.

Bye for now,

The water pump in action...

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You can watch the solar powered water pump working in my final video blog from Malawi:

I'm now back in Bristol, where I'm carrying out more lab tests on the system. I will update you soon with more developments.

Please support our work by donating to this project. Thanks!

Until next time,

Work starts on the pump

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To hear about how I've started to make parts for the rope pump, watch my latest blog video:

Video update from Malawi...

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To hear how the development of the water pump is coming along, watch my latest video blog from Mzuzu here:

I've spent the last couple of weeks sussing out the local suppliers (every other shop seems to be a hardware shop, which suits me!) and working out exactly what size system I should produce.

I have tried to assess the market, including the current demands and sources of water for the potential users. I have therefore toured the Land Management Department at the university, visited a couple of charities that install hand pumps around Mzuzu, The Agricultural Development Ministry, the Ministry for Irrigation and Water Development and the Rural Water Board.

So, after much consultation I believe the most appropriate solar pump would be one aimed at people looking for a step up from the hand pump, but who are unable or unwilling to pay the high running costs of the diesel and electric pumps on the market.

I have decided to test a range of configurations around a nominal system that would cost $700 and supply 8000 litres of water a day from a depth of 7m (the average well depth in Malawi). Although the initial capital cost is higher than existing diesel pumps (a comparable diesel pump costs around $300) there will be virtually no running costs for this solar pump and it would have a lifespan of around 15 years. When compared to a diesel pump producing the same amount of water, fuel and spares would require between $100-150 per year.

8000 litres a day is enough water for 80 inpatients at a hospital and would meet the domestic needs of about 250 people. It is also enough water for 120 cattle, or to irrigate enough land to feed one household of around six people.

65% of the cost of the solar pump goes on the solar panel, the cost of which drops every year, meaning that the pump will only become more competitive as fuel prices continue to rise.

I have also now ordered a motor and all the pump parts. Unfortunately that means that I have now reached the limit of the budget allocated to me by SolarAid and, ultimately, you!

It would be very useful to be able to try and test out different motors, for example the windscreen-wiper motor from a car. These motors are already mass produced and therefore will be considerably cheaper than the industrial motor I have bought in the UK. These other options are likely to be less efficient but I will only be able to find this out by testing them. I will only then be able to evaluate whether the money saved is worth it when compared to the increased size of solar panel needed.

Therefore, any donations made to the project now would potentially allow an even cheaper solar pump to be produced.

I have been very frugal with my budget so far and promise to make the most of any future donations.

Thank you,

Arriving at Malawi

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Watch this video blog, made by Cai Williams, SolarAid's engineering volunteer. Cai has recently gone out to Malawi to research the use of solar powered water pumps.

I have been trying to prepare myself as best I can for Malawi, so I can hit the ground running.

I've been reading everything I can on solar power in Africa, national energy strategies, photovoltaic introduction and dissemination reports, assessments of private verses NGO implementation of water and sanitation in developing countries. I haven't even read the last few papers on the rope pump yet.

Based on this research, it seems my initial plan to attempt to persuade as many local manufacturers and suppliers as possible to add the solar pump to their product list as quickly as possible would be counter-productive. However, I still definitely plan to install the prototype solar pump on as many different depths of well as possible, so that I can confidently specify the system requirements for any system.

However the reports I've read, on the rope pump in particular, state that a new product (such as the solar rope pump) can too easily gain a bad reputation due to poor economic and/or quality control management. So, I plan to carry out a thorough lifetime cost analysis of the pump, and its competition. With this information we'll be able to confidently state exactly the period over which the solar pump becomes competitive. And along with careful quality-control of the solar pumps' manufacture we'll be able to successfully achieve the pump's very promising potential!

The next time you hear from me I'll be in Malawi (and I'll hopefully include some photos) where I can put all these theories to the test. I can't wait!!


The countdown begins!

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I have now booked my flights to Malawi! I managed to save a couple of hundred quid by taking a 31 hour trip back, but this does mean that I get to spend a night in Addis Ababa (the capital of Ethiopia) which should be pretty interesting.

I have also now arranged to visit Pump Aid's operations in southern Malawi. They are a highly successful charity which have installed several thousand hand powered rope pumps for rural communities in Zimbabwe and are now expanding their operations into Malawi and Mozambique. They have a lot of invaluable experience not only in the technical aspects, but also in the very important sociological side of things, which is often the downfall of projects like this. I hope to learn as much as possible from them when I visit their workshop and the site of one of their installations when I first arrive in Malawi.

SolarAid's contacts at the University of Mzuzu's Department of Energy Studies (located in the north of Malawi) have agreed to host the prototype solar powered rope pump. This is great news, as I will be able to take advantage not only of their vast knowledge of solar energy, but also of their solar panels, wells and boreholes. This will save the project a huge amount of time and money. It will also allow a lot more configurations (of flow rates and pumping depths) to be tested, which in turn will increase the range of sites the solar pump will be able to comfortably cater for. All in all, it should be a very worthwhile trip!

Please support our work and donate to this project.

Thank you,


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