Wednesday, 3 August 2011

electric or petrol

why not both?

A common axiom in software development is that if your tool is a hammer then everything starts to look like a nail.

There are people who are "pro" Electric Vehicles and people who are anti EV. Personally I'm a pragmatist and a flexible one at that. I take the position that both nail guns and hammers have their best use still, and that one does not cancel out the other.

A favorite among PRO-EV crowd is that the internal combustion engine is at its end, and that Electric is just starting. This ignores the fact that we have had EV's in society functioning in roles for as long as we have had petrol ones. Clearly this argument is a QED only for the ignorant and very young (and if your older live in the west and remain ignorant well ... that's your fault really).

I don’t think that combustion engines are at a dead end any more than burning gas to heat your water or cook your meal is. Petrol may have a number of nasty disadvantages but it is a very compact energy storage method. We have come to make a large number of assumptions about vehicles and one of the nice things about concept cars is they allow us to remove ourselves from the baggage of conventions and imagine how things could be.

When you examine any of the working and effective electric cars you find at the heart a few assumptions which if applied to petrol engined cars would afford similar efficiency gains. Its just that somehow when you tell people that a petrol car will weigh 300Kg have reduced acceleration, reduced interior comfort and reduced collision protection they go “no way” while being willing to accept it with electric ones.

I submit that a vehicle more like a recumbent trike with some aerodynamics and an efficient fuel injected petrol motor driving electricity generation for battery replenishment would be lighter and sufficiently powerful. It seems to be accepted technology in the diesel electric locomotives we have been using for some dozens of years (nay decades). Such a small motor could be tuned to operate at a static RPM and be exceptionally efficient as well as quiet.

I have no doubt I could make the journey on the highway to work at 80Kmh and have efficiency of the order of 1L/100km and minimal exhaust emissions. Heck, I could probably run it on LPG or other biofuel too

The thing is however we would need to remove the freight and other heavy traffic from the roads as they would make impacts fatal.

Of course we could simply just use bicycles?


Colin Griffiths said...

obakesan said...


thanks for pointing that article out. I see that the batteries are available in cells rather than buying a whole bank. That's quite comforting. However I sill wonder how much better the "leaf" is compared to something like the good old Suzuki 800 hatch which I had back in the 80's. It was great around town and gave excellent economy.

As I mentioned back in may ( the amount of energy needed for moving a mass from one place to another seems to require the same amount of energy irrespective if its generated by burning coal to make electricity or burning fuel in an internal combustion engine. So this will of course result in similar C02 results as long as our power comes from burning stuff.

I see that moving cars over to electric power simply masks the issues of "why are we using cars more" and "can we design our cities to not need them"

Moving more things onto the power grid will put more strain onto an already strained system which is having trouble coping with existing population growth and per capita power demand growth.

Personally I wish they'd put in a decent bicycle lane along the highway and I could ride my bike along that to work (something I can not do now).

Colin Griffiths said...

In the UK they pay a landowner around £30,000 per year for the privilege of having a wind turbine on their land. I could be persuaded to get an electric car if they would let me have a turbine built in my garden. However, I have to say that I use my bike to get to work every day and only average 8000 miles a year in the car (including my trips to Scotland). I do as many miles on my bike and on foot! You are right, people need to be encouraged to use other forms of transport.

Joshie boy said...

This has struck right at the centre of what i've been thinking about. Safety concerns are one of the things that are making present day cars less efficient than they can be. In the last 10 years or so internal combusiton engines have come a long way (mostly with electronic control and direct injection), thing is though with safety concerns, weight has balooned. More safety equipment means more weight, which means bigger engine, brakes, tyres, which means more fuel consumption; back to square one!
Like you say, it would be refreshing if mainstream manufacturers considered lightweight strategies, and used these in conjunction with efficient internal combustion engines.
Ultimately the solution to any energy problem is this: Use less! In practical terms this has to mean cutting down on commuting culture and using public transport / cycling / walking. Otherwise if cars do need to be used, the issue of weight has to be tackled, because i can tell you - from someone working in the engine industry - there is plenty going on there in terms of improvement!It's a pitty weight reduction and proper journey planning has not cottoned on at the same pace!

obakesan said...


a quick point; a friend of mine who was an ordnance specialist with the ADF told me years ago that pyrotechnics (such as would be used in air bags) loose their effectiveness quite quickly. Things like their response time to detonation slows and becomes less predictable within as little as a year. Often replacement schedule is 6 or 3 months for these.

So I wonder how many people are replacing their airbag systems and seat belt pre-tensioner charges every year? I doubt its many. This means that safety is actually a furfie, and you're just as likely to smack into the dash (because your seat belt was loose) and then have the airbag go off pushing you back. It will all look like the systems have worked to a quick and unexpert examination.

Colin: I know what you mean, its diminishing returns with some things. I have a 1989 Pajero V6 as my 'camping car' which sees little use other than camping and as a hauling tool because I (used to) ride about 3,000Km yearly to work on my bicycle (and now use a scooter because I've moved and there is a motorway which needs to be travelled). So that my car uses 11l / 100Km is less significant over the year. Like you my car only does about 8,000Km a year.

I'm not sure why bicycles died in Australia (although I have my theorys) but its impact on our community and its health has been significant.