What I think about green notions and electric cars, as explained in Business Report.
The Publisher and Executive Editor, Simply Green Magazine, Mr. Chris Erasmus, wants to see facts when talking about electric cars. (BR Oct. 14). As he does not furnish us with any, I will be audacious and supply a few. As I can make most things, as long it is not a computer, I was going to build an electric car for my wife and I, to do our short shopping trips. PV panels and a 5 Kw wind turbine were to supply the power to charge the batteries to drive the vehicle. Yes..Batteries… a big technological swearword. For the last 150 years technicians and scientists have been trying to store electrical power in a box and no great strides have been made. Our car batteries today are not any better than the stuff from 1930. I soon found out that I needed about 1Kw to drive 8 km but as you damage the battery when completely discharging it, only 6km. per Kw is a prudent estimate. “Never mind those kilowatts,” said my wife, “will I be able to go to Hermanus and back and see my friends?” “Hmm,” I mumbled, “let me work it out.” I did and found out that to do a wee trip of 90 km. I needed a battery that could furnish 15 Kw/h to ensure that my wife would not get stuck on the return trip. The price of those batteries was already bleddy awful but the weight…? Well over four hundred kilograms! Like having four great rugger players as passengers when my wifey wants to go see her girlfriends. To make the car I had thought to use a Fiat Uno but the thing would not have been roadworthy with all that weight. Lithium batteries are too expensive, can burn and no one knows how long they last. In any case they‘re hardly any better than the normal lead car battery. And you know what, Chris, with 5kg of petrol or 3.5 kg of diesel my wife can do that trip comfortably without having to schlep almost half a bleddy ton of lead. Question for you, Chris: I haven’t been able to work out the difference in weight of these batteries fully charged or discharged. Nick Dekker, Gansbaai.
Hi Nick
We are in Tonga at the moment. We have had an amazing trip so far, diving on the wreck of he Sea Adler , diving lobster on beveridge reef etc. We sail for new Zealand in a week or two. We have lithium ion phosphate batteries on board. Very stable , tried and tested for years in the DIY electric car business in th USA. Batteries are mostly made in china. Life cycles from 2000 to 4000 . They come in cells of 3.6 v. You need 4 cells to make a 12 v super cells. Each cell weighs about 2 kg. we deplete them to 80 % and recharge them fully in 3 hours. They take whatever charge you can throw at them. We only have 600 amp on board but with 720 watt of solar , are able to make water every second day , use the washing machine and charge a multitude of laptops on a daily basis.why not try to get a used battery bank from a wrecked Toyota Prius , the hybrid car. They are readily available in the USA.
All the best
Chris smith