Friday, 27 May 2011

What we've been doing at work.

Josh, Caleb, Willis, Joseph, me and Sam

So I've gone here to work on a wind turbine, I should tell you a little more about it.   The design is actually quite a way from being perfected yet, in fact I would say we have only just started to get results which could be useful.   The principle of the access turbine is in its name- it needs to be accessible to those who need it.  That means it needs to be cheap- made locally and out of parts that are affordable to Kenyans.  This puts the expensive high-tech permanent magnet turbines one gets in the West out of the question.  Instead we are proposing to use car alternators, abundant in scrapyards and super cheap.
An alternator is a generator in reverse; the current is generated in the non-moving coil of wire (stator) as the electromagnet spins inside it.  As they stand they don't work very well for us, a car engine rotates much faster than a wind turbine would. But by putting many more coils of copper in the stator, we should be able to get a current at much lower speeds.  This is the theory, and for the first half of my stay the others have been trying to cram in as much copper into the iron core of a stator.  It is a very slow process, weaving the wire in and out of 36 slots- the most recent rewind has had 80 coils in each slot.  Scratching the fragile varnish insulation can make a short circuit, so winding requires a lot of care and frustration.  One can imagine how annoying it is to assemble a rewind that has taken two days, only to find a short circuit which requires an entire disassembly.
the hi-tech wind switch

Meanwhile I started off developing a simple wind activated switch.  Because the rotating part is an electromagnet, it uses power even when not spinning, draining the battery.  This is not a problem in a car as the the whole system is manually switched on (the ignition), but requires our design to have a switch to energise the coil when there is a useful wind blowing.  I had considered all manner of complex ideas to achieve this based on the blades reaching a certain rpm, but a simple flap lifting when the wind picked up sufficed.  Mark 3 was the simplest solution, made predominately out of the steel side panel of an old PC.  Designing things involve walking firstly to the friendly yet small scrap metal yard to see if they have the material in mind, then if they don't, going to the Aladdin's cave of junk where the owner tries his best to rip one off.

  Fabricating the design is done mostly on the dusty floor using our tools- drills, saws, hammers, angle grinder and an arc welder.  Any more advanced process such as turning on a lathe is outsourced to one of many other businesses in the area.  If our local machinist is busy he lets us use his geriatric old lathe.  Pretty much every standard industrial process can be made here, but only Jua Kali fashion- literally translated as 'in the blazing sun' but has become to mean slapdash.
So about halfway through my time here we assembled our latest alternator with the turbine body and blades Sam had created.  It is his first design, improving upon the many previous prototypes created by the other two, none of which had worked.  We took it down to Hippo Point and tested it with a fairly strong breeze coming off Lake Victoria.  Results were poor- the little bades didn't harness the power required to turn the rewound alternator.  Generation at lower speeds requires more physical load (torque).  Not only did we need to make them bigger, we needed to consider a more efficient shape, given that our current ones were mere triangles of a PVC drain pipe.

I proposed sculpting wooden blades, so after a bit of online research I went to the Kibuye timber area and set about getting a sample blade made.   Amongst hills of wood shavings and decrepit old bandsaws lie carpenters' shacks, bustling with men pushing lengths of wood through guard-free planer thicknessers, powered by crackling bare wires.
The wood yard is stacked with wild timber, rough cut before seasoning so all of the lengths are split and warped, and rarely parallel. I find a length of cyprus which looks okay and explain to a carpenter the alien concept of cutting the length of it at a diagonal, changing the angle every 20cm.  He nearly got it right, only messing the last angle at the base of the blade.  I bought some glue and salvaged the last section, and the following day tried some different guys to cut the angle on the other side and plane the aerofoil. I was pleased with the result, but considered their business minds a little bit greedy.  Back opposite the entrance to home I noticed a couple of carpenters sawing away in the shade of a little workshop.  I decided to see if one of them and do a better job, so I introduced myself and got him going.  Willis was keen and meticulous with his tools, and produced another very commendable blade with a hand saw with much more precision than the Kibuye lot.  I had no problem in leaving him to make four more.  I went back to Jua Kali to prepare a mounting and a geared system- an idea Sam had to increase the alternator speed.  I bought some Chinese bike parts and some block bearings, and set about putting them together on a box section frame.
In addition I have been investigating using the first wooden blade shape to form other plastic and fibreglass blades.  I have created a two-part concrete mould from it and we have cut and heated PVC pipe, pressing it into the mould to form two halves.  After that, the mould has been used by a fibre glass specialist to make a test blade, so already we have quite a few blade options to evaluate.  These have just been crude experiments, the wooden shape has to be tested and developed to find the best aerofoil angles.

In order to see which blade performs best, we need to compare the power generated against wind speed. Without a wind tunnel or an anemometer, we took advantage of the slightly more relaxed road traffic laws here and secured a box frame to the roof of the car.

So in the last couple of weeks we have given ourselves many options, and there will be a need for plenty of further testing and development to find out the cheapest, easiest and most effective design.  It is a shame to leave the project before reaching a significant milestone, but I have a strong inkling I will be back.

Wednesday, 20 April 2011

Island hopping part 1

The dusty sweaty heat of the workshop is intense.  Every day, my light coloured clothes and skin are caked in a layer of brown gunk.  Mixing this with sun cream or mosquito repellant creates a coating of soft brown plasticine.  One afternoon a refreshing wind picked up, carrying ominous clouds over the distant hilltops.  The tree tops swayed vigorously and the mark-i turbine buzzed in a worryingly fast frenzy.  Sitting on top of Douglas the spare parts man's shipping container shop, it normally is very indecisive in finding the wind with its small tail fin, but now it had no doubt.  Then the rain came, occasional big blobs of rain rising to a power shower of warm sweet water.   Brown rivers washed all of the dust and dirt away in no time, and soon the rain passed, leaving a much cooler, cleaner damp air.  

The following morning it was noticeably cooler.  I went out to buy eggs from the stall in the compound of the Marie Stopes nursing home and in true British spirit, chatted to Patrick our day guard.  He asked me if it was true that ice formed on the rooftops of our houses.  I explained to him the concept of snow and how it can bring everything to a standstill.

On Friday afternoon we packed and got in the car to meet up with Elin on Rusinga Island, off Lake Victoria.  We drove through a landscape of enormous Flintstones boulders and got to the Ferry slipway just in time for the 6pm departure.  A loud commotion of drunk men sprung upon us, amused by the unnecessary need to help us push the car onto the boat (a connection between solenoid and starter motor I suspect).  We sat on the roof rack and watched the most majestic sunset, spilling shards of light out through golden edged clouds. Sam pointed out that it looked like the cover of a self help book.  Night fell and we followed some vague directions over a dusty track with Josh still on the roof rack.   As we asked directions, locals joined him as they were going the same way.  Eventually we found Elin and Michael who she had been staying with.  We took the car over some pretty rutted off road track up to the small cluster of tin roofed houses where Michael lived with Mama Jane and their family.  Whilst having dinner, Michael roped me into setting up business with him starting a volunteer tourism business.
We rose at the break of dawn, greeted with large plastic mugs of gritty coffee from Mama Jane.  Two locals on their Indian motorcycles waited for us to take us to the other port on Rusinga.  I was confused how four of us plus luggage (including guitar) could get on the two bikes, but we did, gliding off down the dirt tracks with quite some grace.  We got to the port and waited for the little wooden boat to take us about 10 miles across the bay to Mfangano Island.  The start was much more leisurely than Mama Jane had warned us, after plenty of waiting around a breakfast of Ugi, Chapatti and beans, our boat arrived.  Most of the passengers were being carried through a stinky mire to the boat for 10 shillings (around 7p) but with my pride and gangle I squelched up onto the boat. We faffed for a while and left at 10, three hours later than expected, but only went 20 meters along the shore before we picked more passengers up.  Then we motored off through the soup of flies and algae in the blazing sun.  I amused myself at the sight of the passengers reading a newspaper named 'the Standard' and how different it was to the 'Evening Standard' reading passengers on the tube in London.
20 minutes in and the engine spluttered, forcing the driver to head for land. 200 shillings were handed down the boat to the helmsman, who ran off 'for a spare part.'  He returned a while later on the back of a motorbike with some sparkplugs and we were soon back on the water.  The algae and small flies increased and on the horizon there appeared to be a plume of smoke.  It was apparently an enormous cloud of these flies, visible twenty miles away. A local told us all about the ecosystem here, how the algae was caused by rainwater churning up the algae from underwater currents, and how the entire lake was populated by the Nile Perch.  Introduced in the 1950s, this enormous predator has eradicated virtually all of the other fish in the lake.   Growing up to two meters in length, its white flesh is exported in enormous quantities especially to Israel, creating a huge local economy where people from all over have settled on these shores.  There is one distant rock island on the horizon where twenty thousand fishermen have settled and created a tin city upon it.  A fragile microcosm which will only last as long as the massive stocks remain.

We hopped off the boat at Mfangano and strolled up the dirt track circling the island to meet Adam, a young American who has lived here for five years as a fisherman.  He lived an almost feral existence on the beautiful shoreline in a mud hut, line fishing every afternoon in his little boat.  We were showed our camping spot, went for a swim in the warm waters and then had a late lunch with him and Brad, another American seeking sanctuary from western civilisation.  We joined him for a trip our fishing, taking it in turns to cast the four lines as we drifted down the beautiful coast, watching the birds circling around and occasionally spotting a large monitor lizard on the rocks.  Needless to say we caught none of these legendary beasts, and as the sun set and we headed back we watched a dramatic tropical storm on the horizon with bolts of lightning illuminating the distant hills on the mainland.  Half way back it was clear we were not going to out-run the rain, and as the little boat crashed up through the huge oncoming waves we began to get rained upon by the biting wet deluge.  As I sat at the bow the spray of the lake water warmed me up, I looked behind us as the rest of the crew were huddled and shivering.   Visibility was nothing, so I was very pleased to hear Michael, the Kenyan navigator recognise our beach.  How, I just don't know. 
We heaved the boat onto the shore and fled up to the warmth of the hut where Elin had made some pizza dough.  How much of a treat this was!

Friday, 15 April 2011

The Arrival

After an easy flight from Heathrow, I touched down at Jomo Kenyatta airport, queued for an eternity to check a visa I had already acquired, and exited into Africa.  I was not sure whether I was going to be met by my friend Sam Duby and his wife, Elin, so I formulated a backup plan to stay overnight and meet them the following day (for that was the last incorrect rendezvous correspondence I had heard about).  Despite having no guidebook and effectively having no clue, I was armed with the confidence of coping with the unfamiliar and having a relatively hardened attitude and look about myself for a freshly untanned Mzungu.  I had decided that whilst observing the many young missionaries on the plane, and I had always believed my scruffy cheap green sports bag (aka the Tardis) was a better tool for establishing this look than an expensive strappy backpack.

Nevertheless, my contingency plan was unnecessary as I was jumped upon in the arrivals crowd by Sam, and I was escorted to his old ex Camel Trophy Mitsubishi.  We drove through the chaos of late night Nairobi traffic, past dark silhouettes of skyscrapers and up into Karen, a forest of upmarket compounds.  This was going to be our home for the weekend, staying with Leslie and Michael, an american missionary couple, their 7 month old baby Finch, and their enormous Rhodesian Ridgeback, Simon.  The night guard opened the big iron gates and we drove in, said hello, chatted and slept.  The following day we had a very un-African breakfast in an upmarket restaurant and strolled around Karen's market.  It was clear that my acclimatisation into Africa was going to be gradual, not just culturally but climate wise we were cool up in the forested hills.  We spent the time in Karen visiting different compounds to meet various people involved with projects developing appropriate sustainable technologies for Africa.  Each was heavily guarded, perimeter fences surrounded with razor wire or electric fence, often with pens of savage looking pet dogs. Sasha, a big Russian owned a beautiful plot with an organic farm where we purchased some milk.  Then on to Dominic, a half-Kenyan who showed us his affordable and simple bio-gas system, effectively a big bag which is filled with excrement and methane is tapped off straight to a cooker. Finally we went to see another more substantial concrete biogas system on a large dairy farm.  The swill from the cows fed the gas supply for all twenty of the residents of that compound.
The Rift Valley

From what little I had seen of Nairobi, it was pretty clear that it's possible to live very comfortably here, but the razor wire around the compounds was a reminder of the massive gap between have and have not.  Monday noon we set off towards the have not, though I'm sure we'll still be a long way form its centre.  The drive took us a few hours into the real dusty Africa up to the escarpment of the Great Rift Valley.  We stopped to have a moment in a lay-by on the edge.  For as far as the horizon would let us see, this vast flat land was the birthplace of mankind.  We sat and thought about that, how we'd ventured out from here, discovering all sorts along the way.  Here we were, returned so easily having shrunk the world with aircraft, appreciating the moment with a Coca Cola sold to us by a kid on the roadside.
We descended the snaking road past prudent old beasts of trucks steadying themselves with a trail of the smell of hot brakes, and we levelled out onto a long straight, shimmering on the dusty hot horizon. The journey continued for six hours, stopping just once for mutton and ugali- the staple dish of many here.  It is effectively polenta, although when cooked in an Italian way it may be considered fancy.  Here it is a pale corn block of stodge, mixed with the salty juices of spinach and greengrams.
We climbed the other side of the valley hours later and Beryl (that is the name of the jeep) gave us a blast of hot air in the cab to stop her overheating.  We turned off the superior A104 onto the Kisumu road, the surface deteriorated significantly and Beryl's 4x4 capabilities proved her worth.  Dusk fell on the dusty track with a beautiful sky, and eventually we got to our home in the black of the night.
Our compound is noticeably more modest than the Karen ones, but also less guarded.  We got home tired, said hello to Josh, our fellow Access wind coordinator, and went to bed. 

 So after a day of rest, acclimatising to the massive environmental change my body faced, I have been working the last three days in Jua Kali, the feral and dusty 'industrial estate' of Kisumu. The place has to be seen to be believed.  The weaver birds, who have been engineering beautiful nests in the trees for many millennia look down upon quite a different mess of engineering.  The most part of the work carried out here is motor mechanics, though almost anything can be fabricated or repaired here.  Parts are salvaged from donor vehicles until they are rendered useless, then the metal carcasses are cut up by hand and sold as scrap metal to local smelters.  Teams of entrepreneurial Kenyans operate small businesses amongst derelict wasteland, donated to them by the government in an attempt to reduce unemployment.  The earth mixed with rubble, rubbish and engine oil paves a labyrinth of corrugated iron plots, populated with scores of young men, lounging in the shade.   I can only assume a lot of them are trainees.  We are located in a shell of an old fish market, or space next to an evangelical church.  We share our plot with a communal old black Singer sewing machine used to upholster car seats, a couple of old vehicle shells and a very dark and dingy space at the back where some of the kids skive and smoke weed. Our core operation is currently myself, Sam Duby, Joseph - a self taught local  who has a business installing electric fences, and Calib - an elderly widower who is delighted to help in 'his retirement.'  Alan, a jovial educated car mechanic joins us occasionally, chatting away in a happy manner about allsorts.  He has a fascination with Airbus, and wanted to know all about what I knew about it. 
Calib has been helping me make a wind activated switch and I have been coordinating his every move, too much so in my opinion. 

 He is the sweetest loveliest person I have ever met, he has a heart anyone would warm to and a slightly old fashioned colonial subservience about him.  For many years he worked as a trade unionist on the coast, and then a social educator, supporting villagers to help demand their basic needs.  Last night we were invited to his modest little tin roofed house for dinner.  He had killed one of his hens to cook, head to feet and everything in between in a pan, while the other hens and chicks clucked away around our feet as we ate one of their sisters.  It was almost tear jerkingly moving, this humble old man's humanity.
Joseph and Alan