EV's Electric Vehicles
My ponderings and efforts at solar powered electric transportation
I have developed a fascination with electric transport, I might even admit it is an obsession. I make unusual musical instruments so I am used to challenging projects and have had a lot of joy doing these.
Works in progress include a recumbent solar electric bicycle with a full fairing, a 4 wheeled electric velocycle and a Porsche 924 Martini I am converting to electric. Progress is slow given my lack of readies but constant little bits add up.
My main motivation is to save money (in the long run) on fuel, sparkplugs and leads,oil changes, filters, fuel, points, pipes, etc etc (I have had a bad run with ye olde infernal combustion engine in the last few years) but also to save the planet. The average Australian (who is that anyway?) has a huge carbon footprint chiefly because of the long distances we drive here which makes me wonder why we can't buy such efficient cars as they have in Europe. Personal and business transport has a huge role to play in progressing to a more efficient and less environmentally costly lifestyle and in some small way someone being a working example of an alternative can be a big step towards change.
We have the technology in almost every realm to solve the worlds problems, It is not for lack of solutions we are in this bind, that is for sure. If the government and their big business puppeteers won't help then we have to do it ourselves at a grass roots level, many are. There are over 40000 fully electric cars on the road in the US alone and a quick look at the EValbum site will show you what they are up to on a world wide basis.
Often people argue that the energy is still coming from a non renewable polluting source unless you are charging from solar and not from the grid but the gains in efficiency are huge with electric drive where efficiencies of 95% plus are regularly acheived. Coal fired generators are a lot cleaner than a car engine in producing the power as well.
I predict a huge increase in the use of electric transport in the next decade and in places like China it is well under way (if the world as we know it continues which is by no means assured) and many governments especially in Europe, the US are actively encouraging people to switch over by way of tax incentives and grants already.
The first cars were electric and their popularity closely follows rising oil prices throughout the last century. Check out the film `who killed the electric car' for a look in to the politics of the issue.
My experience so far riding the electric bike have been exhilarating, the silence, the torque, the lack of stench...
I can't wait to be driving the car!
The recumbent electric bicycle
with a full fairing
This project all started by me losing my licence for touching the centre line with my tyres on two occasions on the very potholed road to Nimbin (my local town) in a period of severe PMT, (pre-mardi-grass tension; where lots of police descend on the area to harass the local hippy population in the lead up to the help end marijuana prohibition law reform rally / weekend of harvest festivities, a local tradition for the the last 35 years straight.)
Without a car and living about 30klms from town on a dead end road in very hilly and unforgiving territory, I decided I needed an alternative form of transport that didn't require a license. After the first days of traditional bicycle travel I decided I needed a motor and began a bit of research and so eventually I started this lens to share my findings with others of similar bent.
Up to 200W is the legal limit for an electrically assisted bicycle here in Oz. At 20kmph something like 200Watts is needed which is about what your average human can easily deliver by pedaling and on a normal upright bicycle fully 80% of this energy is dissapated in order to overcome wind resistance with negligable rolling and mechanical losses making up the rest. To do 30kmph it requires around 300Watts (about what a fit athlete can muster continually) and at that speed 97% of that energy is used in overcoming the drag from wind resistance.
With a full fairing recumbent bike these power levels could produce 40 and 70kmph respectively by reducing the drag co-efficient considerably so I set out to try to make a streamlined fairing. I got lots of inspiration from finding the international human powered vehicle association. Lots of info and links there; http://www.ihpva.org/building.htm
On narrow, hilly winding roads that we get here it is a matter of survival to be going as fast as possible and in a summer of 40 degree heat and high humidity it is no fun on the way back home as it is almost all uphill so hopefully this project will result in enough speed and power to keep up with the car traffic, or should at least help to keep out of their way a bit anyway.
I bought a Red Pepper recumbent for $650, mainly because it had a schlumpf mountain drive on the front cog which i wanted to use to make a velocycle (4 wheeled bicycle.) I still am intending to as I think it will be a superior way to go, less frontal area, more stable in high wind and at speed, but the recumbent seemed like it might come about a lot quicker so I am working on that first and practicing welding alloy in the meantime. I made a seat on the back rack for my two kids and added a 200W motor I scored on a flogged out $350 electrified mountain bike which also had the freewheeling front cog needed so you can run the motor and not have to pedal, the mounts for the motor which fitted perfectly which was fortuitous, and a fat set of LiFePO4 batteries which turned out to be pretty trashed as they had not put a cell balancing charging circuit in the battery pack.
These Lithium Ion batteries are what make electric travel so much more practical being about 4x more energy dense per kilo than a lead acid battery and 6x more charges before they tire out and stop working, so although the initial price of purchase is high they represent much better value than lead acid (lower charging efficiency, reluctance to survive deep discharges, short life expectancy in demanding applications, toxicity, weight, lower output, drop in performance as it flattens, all make them less than ideal for transport.) The price of lithium based ones are plummeting and the fruits of hundreds of billions invested by laptop manufacturers are still reaping improvements. Second hand ones are beginning to appear and China has ramped up production hugely. Newer chemistries and improvements are coming online rapidly. They can be recharged at any stage and don't have any memory effects, can be 80% discharged and very quickly recharged without any damage and are still 80% good after 1-3000 duty cycles (depending on the cathode quality) which equates to many years of daily use so per watt hour they are already cheaper than lead acid. The more common LiFePO4 ones are also environmentally safer to dispose of and make than lead acid (and safer to use than LiPo ones which can catch fire if over-charged/discharged.) With coming advances in nanotechnology in the cathodes, new materials utilizing manganese etc. they look set to becoming 8x more energy dense and 4x longer lasting in the near future and titinate supercapacitor technology is getting very good too, sulfur batteries are getting cooler... the traditional electrical storage bottleneck is widening.
I used a 24V brushed motor driving the chain so I could use the gears as the more efficient brushless hub motors most commonly used on electric bikes are not so good on hilly terrain as they have one set torque limit. China has made millions of them. They also make a lot of solar panels. Plugging an electric vehicle into the grid is silly I think especially since you can get the cells really cheaply (under $1per watt ) as factory seconds and solder them together yourself and thereby make a panel very easily. The price of ready made panels is dropping too and wind and solar are actually cheaper than traditional generation technology already. I plan to make a garage with them all over the roof. Solar rebates were available for homeowners here which I had hoped would continue and be expanded to businesses instead of shrunk back more.
If electric car users did this it would be a nearly pollution free ride except for the manufacturing and a bit of ground up tyre and worn cogs dust. Human power is a pretty efficient and fairly clean source of fitness and power too. Being pretty broke most of the time and a busy single dad it has taken so long that I have my licence back and it still isn't finished but it is looking funky and has been a lot of fun.
A test ride confirmed it has enough power to get all three of us up a half decent hill in third gear without pedaling.
It has been a very enlightening project. Now I am making a front bracket for the windscreen from PVC plumbing and have added some flexible Russian mono-crystaline solar panels (30W through the front and a further 10W through the back, more efficient in low light and high temperature and only 300g each) as a roof and made the frame for the tail section from ply and polystyrene and it is remarkably rigid. I now have three Ping LiFePO4 10Ah battery packs and a stereo mp3 system, lights and a 24-12V converter to run them. I recently have been doing some electrical wiring, (I got a 12v amp), I put a bigger idler on the motor to reduce noise and vibration, put a kickstand on, a bit of painting and wiring and considerable fiddling making the fairing.
Things still to do; finish the fairing and windscreen (by Windwrap) mounts and enclose it, I will be using corflute, lycra and polystyrene boxes, make a seat cushion for the kids, wiring the stereo up and lights, and given the extra weight better brakes might be in order too, we'll see.
The fairing is by far the hardest and most time consuming part of the project. Getting close to finishing (I think.) The last .5 percent is always the bit that takes the longest when your project is out of the ordinary you run into a lot of unexpected hassles. It is a lot of fun building it though and I consider it one of the best things I have made already.
The Electric Car Project
1977 model Porsche 924 Martini
I have bought this car, a 77 model Porsche 924 Martini, which had a partial motor, no torque tube or transaxle and a few rips in the seats, rusty, missing lots of bits, rescued it from under a tree in Bellingen after looking out for some time for a small lightweight streamlined uncomplicated car (without power steering etc.) I chose it because it was beautiful, cheapish, ($800), light, (about 1080kg which I plan to shed a fair chunk of given the engine, transaxle, drive shaft, mufflers/exhaust, fuel tank, radiator, alternator, etc will get taken out- amazing all the things that are rendered unnecessary if there will be no burning to do) and it has the best drag coefficient of any production car of that era ; 0.31.
I am looking into motors and will probably build my own axial field motor and controller unless I find a bargain somewhere or have a sudden unexpected windfall. I recently scored a series Advanced Motors 4001 DC motor and gearbox/adaptor plate very cheaply which although isn't well suited to the Porsche could easily go into a different car which I end up making first as it is simpler using a differential. I couldn't resist it. I am thinking a dual cab utility as it can pull around 2.5 tonnes.
I would like to have regenerative braking and I hoped to fit two motors in the back where the trans-axle was (loads of room as the tank was in under there too), driving the CV joints with toothed belt or chain reduction drive of about 6:1, I will put the batteries down the middle and have most of the front left for stowage if they spill into the under bonnet space. I am hoping by the time it is finished the batteries will be considerably cheaper and better. I usually only drive to town once a week so no hurry charging it and a 100km range would be more than I need 99% of the time. (80% of all driving in the world is under 70 miles.)
I figured I can afford to maintain a Porsche if it doesn't cost fuel and hasn't got an internal combustion debacle. Parts are actually cheaper than I expected. Electric motor systems are almost maintenance free, gearless, quiet and efficient, have maximum torque available at any speed/revs and are totally silent using no energy at the lights or in a traffic jam. I'll add some photos as it progresses, it already has beyond what you see in the early pictures. I am pretty excited to have gotten this underway. Lots of calculations and research so far into just how to design it, now there is just the capital to amass for the battery and electric motor stuff. I have bought
I bought what I thought was my last normal car, a Porsche 924 '78 auto which happened to come with a lot of parts I needed for the restoration but within a week I hit a kamikaze wallaby about 150m from my house which went straight under the front, lifted it up and set it down to the right, leaving me pointed at a tree which I hit at about 30kph, so now I have written it off and have all the parts I need and more, so I am selling the excess bits on ebay and stripping it down to raise some money to spend on the electrickery. I think I might make it into a trailer with a range extender in it now. Should look cool especially if I have lycra streamlining it with the car.
I have a small twin cylinder 50cc 4.7kW RC plane motor which will probably become the drive for an efficient and light weight axial flux generator such as are used in wind generators and am scavenging thermal generators from fridge butter boxes to turn some of the huge energy waste in the form of hot exhaust directly into electricity which will boost the output further. I estimate about 8kW will be required to drive and charge a bit as well cruising at highway speed. An aircraft alternator with a gas turbine could be better but I am not sure where to find one. I also have a hydraulic motor/pump which I was intending to build into a regenerative baking trailer for my normal car which could factor in too as for the power it is light and a simple aircraft accumulator could store energy and give it back as needed at takeoff quite well. It could be driven with an electrically activated clutch from the airconditioning compressor from the CV joint.
Guy Negre and his MPI compressed air car is now being made by Tata motors India (which I have been on the waiting list for for over a decade) but I think the batteries won, although I like that system a lot.
I recommend the book `Build your own electric vehicle' by Seth Leitman and Bob Brant which a friend loaned me, it has lots of the necessary calculations and advice for planning it out. There is a bunch of sites on the net about all aspects of the challenge and lots of new companies in on the act making parts, controllers, conversions etc. If anyone wants to partake in a bulk battery purchase let me know.
Hope you liked this lens and feel it helped or inspired you to make a difference yourself.
Photo Gallery - works in progressClick thumbnail to view full-size
Link List - places to find out more
I thought I would add this to save interested parties a lot of time, here is the best stuff i found so far:
plans, calculator, diy controller, forum...
- my site
Mostly musical instrument making
- diy electric car
lots of links and info
- turqoise energy
make your own hybrid out of your car great work by Craig in Vancouver Island
- International human powered vehicle association
- atomic zombie
bike making modding mecca
OTHER EV PROJECTS
I now have 3 more EV's on the go, an Austin A40 utility made in 1950-53 which I am converting for a customer, a '01 series 5 Mazda rx7 and a Holden Scurry (Suzuki Carry Van re-badged for Aussies 1986-7) all of which have taken over the 924 for the time being because I got great deals on major components which were not as suitable for the Martini but were irresistably good value and warranted a change of tack, I am still planning to complete it but it has spent some time on the back-burner. I have gotten Nissan Leaf batteries in for the scurry and bought a LiFePO4 pack for the rx7. Both are nearing completion. The link from the meet the maker page on my site; www.unheardofinstruments.com will show you the whole saga. I am getting excited finally coming close to driving and finally coming to the end of the many frustrations I have suffered keeping my infernal combustion engined cars going.