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The Electric Car

In August 2008 I graduated as an electrical engineer and computer scientist at Saarland University. Just at the time when the world financial crisis started to make it's way to company's decision makers. While I was waiting for replies to my applications, I was left with quite some time to spare and set about using it. I can't really tell what was the first impulse that lead to the plan of building an electric car, but it might have been one monday morning in October 2008.
It had become kind of a habit for me to have breakfest at the St. Johanner Markt (basically an old market square with lots of cafes and pubs around it). On the short way from my flat to St. Johanner Markt I spontaneously decided that I should buy a book as I walked past one of the book stores. So far my plans were to work for an automotive company in some way, so I thought it would be a good idea to buy a book on the subject. I dropped in, went straight to technical section and skimmed over the book titles. I looked over books explaining various systems like ABS, ESP but nothing could really float my boat. Until I discovered a small book called "Die Sonne schickt keine Rechnung" (the sun sends no bills) by Franz Alt. I immediatly agreed with Mr. Alt and bought the book. Then I took off for breakfest.

Motivation

In the book Mr. Alt presented the potential of the energies that are just there. The amount of light for example, that reaches earth every day is enough to satisfy our current energy needs 15,000 times! Maybe they miscalculated and it's just 10,000 or 5,000 times, but still, it's PLENTY. So it really seems arkward that we produce most of our energy with complicated engines and steam turbines by essentially setting stuff on fire.
Now usually when it comes to using obvious energy sources like wind, sun, tides etc. people start thinking about hippies with bad clothing, a spartanic life style and a weakness for narcotics. For some reason those ways of converting one form of energy (like light) to another (like electricity) are stuck with the stigma of "alternative" and are not considered very sexy. Whereas burning what's left of rotten dinosaurs (oil) in eight pots with a few valves and tubes on it (internal combustion engine) is apparently considered extremely sexy. Any explanation?
All this becomes particularly hard to understand when you compare the complexity of the two systems. Lets see what effort it takes to build an run a car. Now I know that the solar panels and "put in the batteries" steps sound a bit optimistic. But think about it, how hard is it installing some solar panels compared to drilling for oil in your back yard?
I am well aware that if I were to run an electric car right now in Germany it would be powered mostly by coal power plants making it hardly any "greener" than a normal car. But then, all the building blocks for getting the power from a renewable source are THERE and AVAILABLE. Now tell me how you want to run a petrol car off renewable sources without us dying because there are no fields left to grow actual food.
I am also aware that right now a kilo of petrol contains about 100 times more energy than a kilo of battery. But then the electric car on average uses 80%-90% of that energy for propulsion whereas the figure is about 30% for a decent petrol car. That means that we only need to carry about 1/3 of the energy in an electric car to cover the same distance in the same time (remember, going faster uses more energy). That leaves us with a factor of about 35 to make up for. Now I leave it to you to find an example where humanity got better 35 times over a certain amount of time (how about the evolution of micro processors?). So I think it can be said that the electric car is easier to build and easier to run off renewable energies than the petrol car and thus definitly worth a closer look.
Why wasn't it built in the first place? Well look at the financial wealth of the oil exporting countries and then consider whether any more questions need to be asked. Apparently, doing what is profitable over short terms is still preferred over doing what is necessary (and profitable over long terms).
Often I get asked whether it is any cheaper to run an electric car RIGHT NOW. I would say: no. Battery costs are so ridiculously high and life expectancy so ridiculously low that all the savings in fuel and maintenance are easily made up for. But that just isn't the point. The concept is simpler and more efficient (or simply more elegant) than it's predecessor, the internal combustion engine. So you don't need to be a prophet to be able to tell that it will eventually take over. Just like the transistor replaced the vacuum tube.

Off we go

So now, I was motivated to dedicate myself to harvesting renewable energy and building electric cars to run off it. But thinking about it doesn't make it happen. So I started by coming of with some specs.
First I considered converting a go-cart to run off electricity. Picturing myself in a go-kart riding between lorries, cars, SUVs and what not made me drop that idea after about an hour. Then I started looking at buggies. Their lack of practicality made me drop that one, too. So I ended up with the plan to convert what most of us are using: a regular car.
I started to use my less than average physics skills to make some calculations about energy needs and so on. That quickly let me conclude, that I should aim towards a city car for short distance trips unless I wanted to spend a fortune on batteries. To bring success to a reachable distance, I set myself some limits: Now, as I mentioned, I had a lot of time to spare. I wanted to use that time to build one of the most expensive components myself: the motor control. Now building something thats already there is usually an unreasonable decision. But after looking over some literature I decided that I should be able to come up with a basic motor control by myself instead of spending a few 1000€ on it. Plus I love fiddeling with electronics and computers just as much as other people love playing an instrument. So soon my desk was cluttered with all sorts of electronic equipment and after about 1 month of playing around my little 3 phase induction motor finally started to spin with its torque and speed being controlled by a computer program.

Credits

Allthough I might have been the one who started this project, a lot of people have joined in along the path and somehow contributed. The most obvious contributor is my friend and former working colluege Mr. Thomas Kuberczyk. He has given me advice, he has given me books, he has lent tools to me and he manufactured all of the circuit boards I used in this project so far. Thank you so much for that.
I also want to thank all my friends and relatives who have expressed their interest and sometimes excitement about the project. Getting this sort of feedback has also been a huge motivation to carry on. This also includes everybody who has written me Emails.
I still don't really know where this is going, but I want it to become something that not only I can be proud of.

Pictures

To see more pictures of my work, check out the german album.