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Posts Tagged: Ideas

Another hybrid?

Sunday 4th December 2011

At first glance, electric cars seem to be a good idea. Certainly at current prices, using electricity seems to be a relatively cheap way of fuelling a car. And for many people, who mostly use their car to make short journeys, the range issue isn’t generally a problem.

However, most people also use their car for occasional long trips. For example to visit friends or relatives who don’t live locally. And so although people generally only make short trips, they still need it to be able to make longer journeys on occasion. I think this is probably one of the major barriers preventing wider uptake of electric cars at the moment (price being another big one; a comparable EV typically costs 50-100% more than the alternative conventionally-powered car). Even if you only make short trips 95% of the time, most people don’t want to buy or rent another car for the other 5% of the time.

But perhaps there’s a way to have the best of both worlds. At the moment, certain cars have a “hybrid” system. Here, a traditional internal combustion engine (ICE) provides power in the first instance, and this is supplemented by an electrical system which collects energy which would otherwise be wasted (in braking etc). Seems like a good idea, although I do find it surprising that many of the cars which use this system don’t actually seem to do it very well. For example in the real world, a Prius only seems to be about as efficient as other mid-size cars (e.g. the Ford Mondeo or the BMW 3-series) which use reasonably-sized diesel engines, and are much less efficient than many smaller cars which use small engines with forced-induction. Only the Prius is more harmful to the environment, once you take into account the materials used to manufacture the hybrid system…

I reckon that this might be the wrong way to go about making a hybrid drivetrain. Rather than having a drivetrain that is mostly ICE and partly electric, why not have the balance the other way?

By that I mean, rather than fit an ICE drivetrain with a slimmed-down electric drivetrain, why not fit a small engine to an electric drivetrain? So for short journeys you can run solely from the batteries, which you can then charge as you need. But then if you want to make a longer journey – or if you run out of electricity – you can fill up with petrol or diesel and start the engine.

I can’t see too many downsides to this. It’d be harder to package and would increase the weight slightly, but I guess that this is only the same problem as is faced with the drivetrain on other types of hybrid. But in this solution, the car gets the best of both worlds.

Of course, I’m not a mechanical engineer so there could be problems I haven’t foreseen; perhaps there’s a good reason why no-one uses this drivetrain (if that’s correct. Maybe some cars do, and I just haven’t heard of them). But I really can’t think of many negatives which would outweigh the obvious benefits: EV efficiency for smaller journeys, and ICE range for longer ones.

All this being said, has anyone actually worked out whether EVs really are more efficient than cars with an ICE? Or does using an electric drivetrain simply move the location at which fuel is consumed away from the vehicle? I actually don’t know the answer to this, although if making a journey using an electric car costs less per mile, I guess that’s a good hint.

Posted In: CarsEngineering Tagged: | 3 Comments

The Sum of the Parts

Friday 20th November 2009

This is something I’ve been thinking about recently, and was going to write some of it as a comment on Andy’s most recent post, but thought I may as well expand on it here.

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As most of you probably know, I live in Wales at the moment. The Welsh are fairly patriotic and proud of where they come from, so being English I naturally come in for a certain amount of stick, and it kind of makes you think about the whole nationalism thing.

Wales is currently in the process of devolution; moving power over Wales away from Westminster and to the Senedd, a really rather snazzy building in Cardiff Bay. I’m very uneasy about the idea of devolution. I suppose a cynic would suggest that I’m bound to be, because I’m and Englishman and devolution removes power from England, but I don’t think that’s why. I think it’s just such a backward step; instead of drawing dividing lines around the country, we should be coming together as one and moving forward. If there’s a Welsh government, a Scottish government, an English government and a Cornish government (yeah, Cornwall wants devolution too. Crazy, isn’t it?), then each individual country is going to be less well off in pretty much any respect than if we all stayed as Britain.

Even the word, “devolution”, hints at this. It’s the opposite of evolution; a regression from a devloped state towards a more primitive one. I can’t think of a single reason why anyone would support it, other than pure nationalism. But that’s a rubbish reason. If we remained as Britain, with one government, then how does that get in the way of patriotism? A Welsh person can still be proud to be Welsh, in the same way that a Geordie is proud to be from Newcastle. You don’t need to be an independant nation for that to happen.

So applying the same logic to Europe, surely we’re better off a part of it? In fact, I’d go one step further and suggest evolution; a United States of Europe. Why is that a bad idea? Each country should still be able to govern “internal” affairs, in much the same way as American states do, but it makes sense for one central government (made up of representatives from around Europe) to do everything else. If that happened, a united Europe would wield more power in international politics than it does currently, because at the moment the power is diffused between a number of countries.

Like with devolution, the only argument against this that I can think of is nationalism, but again that’s a really awful reason. Using America as an example again, most Americans seem to be proud of their state and of their country; the fact that the state is one of 50 neednt undermine that patriotism.

Posted In: Politics Tagged: | 8 Comments