So, you’ve probably heard of Speed Week where every September you can scream your vehicle down a 5 km dirt track at Hakskeen Pan in the South African Kalahari desert. What you may not have heard of is “eco speed week”, where you can do the same but with your alternative fuelled vehicle. Don’t be surprised if you’ve not heard of it because neither had I until August this year! Bob Bond, of Tshwane University of Technology, has been trying to get this going with the Speed Week team, headed by Jan Els, and this year they and invited ewizz and Melex to participate. Even though this event is at the other end of South Africa, the opportunity of being involved in the first eco speed week and to promote our electric vehicles was too good to miss!
The ewizz / Melex team consisted of William “The Joker” Jantjes, an electrics wizard and RC enthusiast friend, Naveed “Crash” Maqbool the electrical lead for the UCT solar car and me, Andy Le May. With only a few brief conversations with the organisers, and this being the first event, we were not sure of the challenges were going face, so we decided to cover all the bases and take a Melex road legal electric golf cart, this would be good for the drag, and two electric scooters, the ewizz Thunder 5, for speed and the vmoto e-max 120L for range (on-loan from Imperial Green Mobility).
With 1200 kms to cover it was going to take a whole days drive to get there so William and I were up at 4 am on Sunday 15th and checking over the trailer we packed the night before. We got her hitched up to our 98 Prado diesel and headed to pick up “Crash”. Now “Crash” got his name for a different reason, but somehow it end up being quite apt for what happened next. You see Naveed was so excited about coming on the trip that he stayed up all night, well not all night because he decided to take a power nap at about 4:30 am and unfortunately slept through his alarm and all attempts by us to call and shout in his direction. So this is how we started. After attempting to raise him for an hour William and I decided that we had to set off or we would not make it in the day.
The weather was ferocious that Sunday morning with headwinds gusting up to 50 km/h. We were carrying the aerodynamic golf cart, two scooters and all the bio-diesel for the journey in two green drums. The bio-diesel is made from waste cooking oil by Craig & Bettina Waterman at green-diesel and, of course, as we were going to eco speed week we had to make the trip as eco friendly as we could! We’ve been using their bio diesel in the Prado for the last two years and Craig & Bettina deliver a drum to our house when we need it. It’s more environmentally friendly and about R1 cheaper per litre. With all the weight of the trailer and that headwind it was hard going, but as we headed north the sun rose and the weather gradually got better. However, worryingly, we had some problems with the engine missing under high load especially going up the passes where we were down to first and second gear and had to feather the throttle to stop it from getting too uneven, and the engine diagnostic light from coming on. It felt like fuel starvation and I had experienced something very similar to this on a long trip we did recently around SA.
Around 8:30 am we get a call, yes you guessed it, crashed out “Crash” had finally woken up and was distraught that he had missed us and potentially couldn’t come. It was going to be hard for him to make it all the way to Hakskeen pan on public transport but as luck would have it for him the engine fun we were having meant we were going slowly and would have to stop the night in Uppington to visit the Toyota dealer on Monday Morning. So we made a plan for him to take the overnight bus and meet us there. William and I just cruised along for the rest of the day eating the sandwiches and smiling at the extra rations we had inherited from our tardy chum. There were lots of stop and go’s on the way but we were very lucky and pretty much sailed through all of them, but not without some consternation from William who ended up swerving around as we approach some of the checkpoints. “These guys! I can’t tell if they want me to stop or go, drive to the right or left of the bollards” he said. Such were the variety of hand signals and robot colours we encountered.
As we approached Uppington from Calvinia the clouds slowly disappeared and we were left with the clear blue desert sky. The night by the river in the River Bank Lapa was very restful, a beautiful spot to unwind after the journey and early start. Next morning we were up early and keen to get going. The breakfast was excellent and we were feeling good. Now to get Crash! He had managed catch the bus, stay on it and keep his cell phone charged, this time, so we got a call. William “The Joker”, answered and said we could see the bus and we were waiting for him on the corner. We were actually still on our way, but we both felt he deserved a bit of a tease after keeping us waiting in Cape Town. We arrived a few minutes later at the bus stop with William still teasing Crash, “I can see you”, “turn around”, “just in front of you”, “no the other side”. After profuse apologies from Crash the crew were finally together and we headed to Toyota to sort out the engine power problem. The last time it happened we went to Toyota in Cape Town and they had the car for a week and couldn’t find anything wrong with it. We had the car serviced and all seemed to be ok again. So this time I suspected the diesel filter. Craig had told me that sometime folks had problems with the filters when they first went onto Bio diesel because the different fuel densities tend to lift the dirt in the tank and clog the filter. Last time we put it down to dirt in the fill we got during the trip. Perhaps there was still some of that left in the tank as it was only a month or so ago. William was sceptical, but we got another filter and changed it in the car park. “Low and behold”, problem gone, and the Prado was back to full strength. So we grabbed some trip food, hitched up the trailer and headed north to Hakskeen Pan.
A couple of hours later we arrived at the Pan, only recognisable as the correct place by the “Speed week” sign, which, although large, disappeared in the vastness of the landscape. What a crazy place, a massive flat barren space bordered by shallow hills all around, but you could immediately see why the Bloodhound team had chosen this place for their 1600km/h attempt at the world speed record in 2015. The road to the site was about 5 km of bull dust, that super fine stuff that gets everywhere. Our kit and vehicles were looking quite clean but this road put paid to that. On the site there was a large Bedouin style tent where all the music, booze and food was happening. Overlooking the event was a large air-conditioned MTN container for the officials and press, and funnily enough there was a golf cart just outside and guess what, it was a Melex cart! Just down the hill slightly were 4 very large permanent container toilet and shower blocks with hot water, and about 100 yards from this about 50 kitted out tents set up by the organisers for visitors. We had a little wander around, met some of the speed week team Jan Els, Theo Stander and Anton Dekker and sorted out a few logistics.
Next, unload the trailer put up the lapa’s. The sun was already crazy hot and coming from Cape Town we were not quite ready for the temperature! But hey, it was great to be in the sun, as this winter has been pretty cold in the Cape and I was determined to get a bit of a tan.Now time for some fun! Crash didn’t have a licence, he had driven a little somewhere but couldn’t ride a scooter so we gave him the golf cart to have a go with and the three of us had a little drive around the site. The electrics were getting some attention and it wasn’t long before one of the film crews covering the event came to talk to us. These guys were from Ignition and looking for a story, they were very interested in what we were doing here and what we were planning with the UCT solar challenge car. So we grabbed a couple of beers, showed them around our vehicles and did a couple of interviews.
We spotted Bob Bond’s team from Tshwane University of Technology and we headed to see what they were planning to race. They had a very interesting car “fire of the dawn” and, of course, Crash was all over them as this is exactly what he wants to build. Johannes (De Vries) their head technical guy was very helpful and kept us amused for a long time with their war stories from doing the previous solar challenge. We’d not seen the insides of one of these cars up close and with the solar top off you could see the amount of work the team had put into building this custom solar electric vehicle.
They had three 48V (Volt) 40 Ah (Amp Hour) Lithium ion packs connected in parallel giving a maximum of 5700 Ah of power. This was connected to a 48V 350 A (Amp) controller matched to a 5 Kw (kilo Watt) Brushless Direct Current (BLDC) motor which was driving a three chain drive system to power the wheels. The solar panel on the top was designed as a 1 kw array though there were a variety of issues that the team had encountered along the way that had reduced it’s efficiency. One issue was the damping on the front suspension. On the race they hit a pothole at speed and the top of the suspension rod shot up through the solar canopy and punctured the solar array. Another was partial shading of the solar array by the drivers cone. This caused the energy being generated in the other cells in that group to channel energy to the shaded cells causing them to heat up and melt the glass above it, hectic. Johan said this can be fixed by integrating reverse bias diodes, but then you loose a bit of efficiency. Lastly, because they only had a very short time to put the whole unit together, when they put a glass laminate on the cells and there was a problem with the adhesive, which was blistering between the laminate and the cell causing partially shading. Johan considered these challenges as great opportunities for the students to learn about manufacturing and already had his sights on building the next version with the latest pre laminated higher efficiency wafers.
Although about 8 teams were schedule to come, in the end we had three teams pitch. The last team that came was Daniel Kriel and Carel Ballack in a converted 2003 Jeep Grand Cherokee sponsored by the Copper Development Corporation. This had a BIG 36 Kwh, 600 Volt, 60 Ah Lithium ion battery pack. The cells were under the bonnet and in a special area where the rear fuel tank was. Where the gearbox was there was now a big 70 Kw industrial AC (Alternating Current) motor. It was quite a machine! The electric drive systems was something new for us, because rather than a conventional AC controller this conversion used an inverter to convert the DC (Direct Current) battery current to a 380V AC signal and then a VSD (Variable speed drive) unit to create the 3 phase AC for the motor system. Managing all the batteries was quite a challenge and they had an Orion Battery Management System (BMS) to balance and monitor the pack and each of the 160 cells. To see this large 4×4 cruise around the site completely silently was awesome and this car had plenty of power and torque.
It was great to spend time with other enthusiasts, share knowledge and check out their machines, but now it was time for us to get ours ship shape. The Melex road legal electric golf cart has a 5 Kw AC motor driven by a Curtis 1236, 48 V, 450 A controller. This was powered by a pack of eight 6V Trojan 220 Ah Lead Acid batteries and on the roof we had a 250 watt solar panel as a trick charge for the batteries. We had a high ratio differential and the biggest tyres we could find. The roll cage and the solar panel would not be helping with the aerodynamics but we were hoping for over 50 km\h for the speed test.
The “Range” scooter was the black vmoto e-max 120L with a 5 Kwh (extended battery option) 48 V 104 Ah Lithium ion pack. This was connected to a Sevcon Gen 4 48 V 180 A controller which is driving a 4 Kw BLDC motor. These scooters have three drive modes and can do between 100 and 200 km/s on a charge depending on the speed mode chosen. Being only 4 kw, the top end, in the fastest mode, is limited to around 75 km/h but lower speed means less energy wasted fighting aerodynamic drag and so the range is very good. We did the calculations and there wasn’t much in it between going faster or slower. With the extended battery pack we were hoping for around 150 km, and rather than go slowly we though it would be much more fun to go a bit faster and do a top charge during the race.
The “Speed” scooter is a two year old ewizz Thunder 5. This has a 2.9 Kwh 72 V 40 Ah Lithium Ion battery pack. The controller is a Chinese 72 V 90 A unit driving a 5 Kw BLDC hub motor. This ewizz Thunder 5 has done over 15,000 km and should get around 90 km/h. These BLDC motors are incredibly efficient and are built into the rear wheel, so there are no chains or gears to worry about. Less maintenance means more reliable, even in the desert heat and dust. That evening was spent over a few beers with the teams working out what racing categories we would have, what events to run and a schedule. We decided that we should have Tuesday for paperwork, preparation, scrutinising, tweaking and photo’s with the Wednesday for the speed timed runs, Thursday for a 5 hour endurance and then head home on the Friday morning. Now we knew what we had to do, so all minds were focused on tactics and strategy that night.
The first event would be the timed run, or drag. None of us really had a chance against the 4×4, that was in a different league, and hence category! With 33 Kwh of battery power and a 70 Kw motor they were sure to get the highest speed, this year. The Tshwane solar car was much closer in terms of power to us and we felt we could give them a run for their money. All the vehicles have to be scrutinised to make sure they are safe to race. The duty of managing that fell to Anton Dekker, who was extremely thorough. Pretty tough job for him as he was dealing with a lot of very new technology. Much of the tech is the same, but it’s a learning space for all of us and I really enjoyed getting under the hoods of a variety of electric vehicles.
There’d been some playful exchanges between the teams, mainly by William “The joker” on our side. Johan had been claiming that they should be able to get 100 km/h from the “fire of the dawn” and so a little banter and competition was in the air. After riding the ewizz Thunder 5 William was pretty confident that we should be faster, so his mouth was in overdrive. On paper it was pretty close. We both had 5 Kw BLDC motors, so power was pretty similar, we were running a higher voltage but they had a more powerful controller and more amps to play with. The solar car was very streamlined but heavier. So it was all to play for, game on! The next day, after some last minute adjustments, we all headed down to the start line. Theo Stander and Anton Dekker from Speedweek had kindly set up our start 1 km from the speed trap. There was no point us being 5km away like the gas-guzzlers because we weren’t going to be reaching 250+ with these babies. Each team would get a couple of runs to see what speed they would get. First off was Carel and Daniel in the 4×4. They headed down the track and created quite a trail of dust so we knew they had done well. The official speed came over the walkie talkie 132 km/h yup we were all impressed! That’s what a 70 Kw motor can do for you. I mused for a second about that kind of power in the scooter or a golf cart would be like.
Next up was us with the Melex road legal electric golf cart. Using the motor controller software we’d set the motor RPM and the current to the max 6000 rpm and 300 amps. So she was set for all out. I was kitted out with the full race gear. This is the same gear I use on the Honda Fireblade on the track and this monkey suit was getting pretty hot so I was very keen to get going! The marshals had one last look at the cart and I lined on the start line and let her rip. With the amps set to max the acceleration was actually quite fun and she whizzed pretty quickly to max speed. The speedometer was telling me 60 km/h and the big wide tyres we had on her felt very stable even on this loose surface. There was no point ducking down or anything as the roll cage was causing quite a lot of drag. So through the timing area we went and I headed to see what we had done. 53 km/h, not bad for a golf cart.
Now for the ewizz Thunder 5. I gave her full throttle and tucked tightly down behind the steering. The track was quite slippery with loose dust and dirty but she felt pretty stable all the same. I wedged my self back in the seat as far as I could and peaked through the top of the helmet. We were full out, the speedo was edging up tiny amounts and was nearly touching the 100 mark as we went through the speed trap. I felt sure we were close to the 100 mark. The surface was pretty slippery so I slowed down carefully with the back brake only and turned round to go back to the timing tent. Before they give you the times you have to do the interview, I was keen to get the speed but half the point of the trip was to get exposure for the electrics. 5 minutes of blab later I found out, 89 km/h. Damn, the speedo was definitely near 100! Ah well let’s have another go!
This time I thought I’ll lie on the bike head first with legs out the back to see if this reduced drag, this later became known as the spatchcock chicken pose, so named by the timers. I got up to 90 km/h quite quickly but to get the “spatchcock position” I’d have lie flat. I edged back as far as I could but needed to get further back to really get flat. So I pushed back on the steering. As I did I hit a patch of soft stuff and the bike started a very scary speed wobble. Rather than being neutral on the bars I was now pressurising and the steering started oscillating was harder to dampen. Luckily it didn’t escalate and I got her back under control and though the speed trap we went. I couldn’t see the speedo as my head was right down. We got to the timing tent and did the interview again and waited for the time. I was really hoping for some improvement. Again 89! Bugger, so much for Spatchcock!
We’d set the starting point, but had we done enough to beat the Tshwane team? I got back to the start line to find them putting the finishing touches to their car. They had all the fairings and cowls on now and it really looked very streamlined. Their driver “Sputnik” was feeling a bit unsure of the surface and set off carefully. We could hear the motor pitch increasing slowly. She was definitely off the pace and perhaps just feeling out the track on this first run. I can’t remember the exact speed but it was about 55 km/h. Back she came and off for a second run. This time she got about 60 km/h. You could feel a bit of tension in the team, there were a few words exchanged and talk of driver changes but she assured them she was getting there and that she wanted another go. So Sputnik lined up at the start and this time she went for it. You could clearly hear the pitch of the motor climbing much quicker from the start and she was creating a good dust train behind her. So what was the speed? Earlier, while drinking, the team was talking about 100 km/h. The radio crackled and Theo announced it was 75 km/h. The team were a bit disappointed. It was time to “Make a plan”.
They removed the large aerodynamic solar panel wing leaving the basic car below resembling something out of the earlier days of formula 1. Their plan was to see how fast they could get with just the battery pack and with potentially less drag from the wing. Again Sputnik lined up and headed off at full tilt and they we all waited for the result. Over the radio it came, 75 km/h. This was quite funny because we had tried a different aerodynamic approach and for us it had made no difference either. Bob was convinced that the car should do more so he opted to have a go himself. He lined up the car on the start line and headed off, and the speed? 72 km/h, his extra weight actually made the car a little slower! So that was that, 4×4 first, scooter second and solar car third though actually we were all racing in different categories.
That night was more banter and beer, but the eye was now on the 5-hour endurance race. We were starting at 10 am so the Tshwane solar car would be racing at the optimum time of day for its solar panels. If they could pull 60 km/h for 5 hours they they’d get around 300 km. This would be pretty impressive and be hard to match with the electric scooter. The 4×4 would be quite heavy on energy usage but they had a 33 Kwh battery pack, nobody had any idea of how far that would take them but they should get over 100 km. For this race we planned to use the black e-moto scooter as it had a 4.9 Kwh battery pack and some clever electronic modes to limit power and extend range. However, it was a toss up as to which speed mode to use and when. Should we go faster and try and recharge or slower and be more efficient. How much power could we take on in the time allowed? How would the conditions on the day change our strategy? We also wanted to give the Melex golf cart a go on the endurance however we knew the range would be rather limited as we only had a 4.8 Kwh battery pack. So less power than the scooter and a lot more drag and transmission losses.
Thursday was a bright and clear day, perfect for the Tshwane solar car. Theo, Anton and the rest of the speed week team had been busy setting out the course for us on the Hakskeen pan dirt with their road grader and had crafted an inner track marker of earth. The circuit was about 6 km and had a couple of long straights combined with 3 sets of sweeping S bends. Those loose dirt corners would be fun at speed for the road tyres on the scooter. We had the two vehicles entering and I decided to take the Melex golf cart as I had been playing with the controller to try and find the most efficient settings. My plan was to start low and then work up. I hadn’t tested too much because I didn’t want to use any battery power before the race and I knew I could easily change the settings. William was on the vmoto e-max 120L , his plan was to start in “normal” mode and see how we went. He should be able to do around 45 km/h and around 160 km at that rate. “Crash” was doing coms and would take over once we got started and had more of a feel for the race.It was quite a spectacle as we all lined up.
With such a difference between the field it looked like something from the cartoon wacky races. One minute to go and we donned our helmets and gloves, the ignition cameras all got ready, we posed for a couple of last minute pics and then we were off! Well every body else was. I had set the power so low that I was heading off at a snails pace. It took me about 20 seconds to find and increase the right parameter in the controller handset and then I was away too. As expected the 4×4 was ahead and they were going quite quickly, perhaps too quickly. They were closely followed by Tshwane and William.
William was doing his version of “Spatchcock” to try and lower his drag, which for him, mainly consisted of trying to get his whole body in the foot well of the scooter. As expected the loose dirt on the corners were tricky, like riding on ice, and William was rightly being very careful. Tshwane were doing well. The solar array was giving them a nice continual recharge of power so they were able to drive more aggressively and keep a good pace. I was dawdling along at the back and doing calculations in my head based on the power consumption readings I was seeing, and trying to work out how we would get the best range. It seemed that around 25 km/h was a good pace that should give us around 50 km. The nice thing about the golf cart was I could put my feet up and just cruise along. No need to contort myself, like before. The camera crews were positioned along the way and so in the corners I tried to make it look a bit more exciting, as though I had to wrestle with the steering to control the vehicle, suspecting I was faking it, they snuck up behind me on the straights with a camera in the back of a bucky and caught me with my feet up. We carried on for about an hour and then Tshwane stopped, something about too much heat, but within a couple of minutes they were going again. Not for long though, about 30 minutes later they stopped again and this time they had broken a chain. The luck just wasn’t’ with them.
As this was happening the wind started to get up. This was fine in one direction but had quite an effect in the other. Filling everything with dust and slowing us down. As the day wore on, the wind built more and more until, at times, we were engulfed in dust to the point we could hardly see what was in front. There was a clear risk of hitting another vehicle. With this wide open space we could see the dust storms tracing across the pan hot, dry and dusty but beautiful and majestic too. Crash had been doing his support role, keeping in contact with us, telling us what was going on with the other teams, refilling the water bottles and throwing them at us as we were passing control.
Now it was time for him to have a go. Crash took over the Golf Cart, I went on the scooter and William went to chat / tease Bob and Johan from Tshwane. We carried on for another hour and then decided it was time for a pit stop and some recharging, both the batteries and us. 1 hour later we were rehydrated and had another 20% in the scooter. The scooter had about 50% power left, so we should be able to ride 50 km at the top speed. We decided to just go for it and see how far we could get. I was blasting as fast as I could and with 15 minutes to go we were about 2 laps behind the leaders Daniel & Carel in the Jeep Cherokee 4×4. They had done 25 laps and finished for the day, presumably out of battery power, but we had 10% left. I felt we were in for a good chance of catching them, but the power level and time were against us. At the end of lap 24 we were 6% on the power and had 9 minutes left. At 6 minutes a lap we might just do it! I got through the first set of chicanes having to do motocross style foot downs to keep her upright and headed down the back straight. The wind was behind me, so I was making good time, the clouds of sand were following along. But as I passed parallel with the control the bike started loosing power, slowing down. “Could be entering a ‘limp’ mode”, I thought, but still there was 5% on the power gauge. The electronics were limiting my power but there just might be enough to finish and I had 6 minutes left, so I kept the throttle full. Then a minute later, the bike cut out completely. The digital dashboard was off and just the side stand light was illuminated. I thought for a moment that the stand switch was faulty. With 5 minutes left there was still time if I could get going again. I worked the side stand switch back a forward and tried turning the ignition on and off, but nothing. We were out of battery and out of the race! Damn, so close, if only I’d realised the gauge was over reading and gone a bit slower on the previous laps we could have made it.
Crash came over from the control point and helped me a push our bike back to our pits. In the end the bike had done 24.5 laps and 147 km and were only half a lap behind the Daniel & Carel. Although disappointed, actually we were pleased. We had a great last night with the other teams drinking and gassing about how we could improve next year. Many thanks to Jan, Theo and Anton, and the rest of the team from eco speed week, for making us so welcome. We’ll be back to show what our new electrics can do in the 2014 eco speed week.
Article By Andy Le May, ewizz, Jan 2014