you beat me to questioning l/km

but what about for rods per hogshead!

Area

If my maths has its powers of ten in order then it's 0.039 square millimetres. That seems too small to me.

58% is nonsense

What counts is the marginal impact of adding extra electrical demand.

Most of the time hydro, wind etc are used to their maximum capacity and the extra burden is taken up by carbon fuels. If you increase electrical use by 10% then that has to be bet by carbon fuels. It is not coming from hydro.

The impact of building a hydro dam is certainly not zero. Apart from the impact on the river etc, there is also all the building effort + concrete etc which is at least as much as the building materials needed to build a carbon burning station. The important thing to do though is to amortise these costs over the life of the power station (50 years or so for a hydro station). When you do that then the building costs are not that big.

While we're in a pissing contest, the Canucks are nowhere near as good as us kiwis. Around 80% of our electricity comes from renewables - mainly hydro.

The only thing shit about battery vehicles...

...is the range and refuelling arrangements. If performance is your main goal, an electric motor will give you far more power to weight than an equivalent internal combustion engine these days, with a much better response curve (as in, full torque all the way from 0 to 50,000 or more RPM).

Sort out hydrogen fuel cells and the infrastructure for them, and believe me you'll be loving that journey along the M40 right up until a traffic cop pulls you for doing 150mph in a 70mph zone. Smoother, quieter, and with comparatively more poke out of a power plant half the size of that chunk of metal you currently have under the bonnet? Yes please.

http://www.youtube.com/watch?v=-xitMWUfeLk

Even a beast can be economical

Based on a 2000km trip across EU coming back from holiday last weekend a modern diesel six-seater can do:

UK/NL - 50mpg = 5.64 l/100 @65-70 mph

SR - 47 mpg = 6.01 l/100 @80 mph

CZ/SK/BG/HU/A - 46 mpg = 6.14 l/100 @85mph

DE 35 mpg - 8.07 l/100 @ 105mph (average), 95-110

That is for a family car which is about twice the size of a golf. I have yet to see a leccy vehicle of this size and I will be surprised if it will be able to deliver an environmental footprint which is comparable. I have also yet to see one capable of keeping up with the psychotics on the autobahn. There you are either at 60mph with the trucks or at 100+. Otherwise someone will ram you from behind trying to do 150+

Re : give a good range (say 500 miles)

My Touran weighs 1700kg, can do ~120mph, and has just averaged 47mpg to Switzerland & back. I routinely get >600 miles range. So it's not just small diesels

Re : they every considered how much fuel is used in recharging...

Far less than leaving your engine running.

The rule-of-thumb is turn off if the wait will be >10secs.

Yes

" Remember that Soylent Green ..."

I read the book (Make Room, Make Room) and nobody ate anybody. That was purely an invention of the makers of the truly crappy film adaptation.

Rule of thumb

And you've researched your rule of thumb thoroughly have you? Thought not.

It will vary massively from car to car. The bigger the engine and the higher the compression ratio the more fuel will be needed and it will be exponential. Generally bigger engines will not only take more energy to start, but they will use more fuel replacing the lost charge.

Add to that the fact that an older battery is less efficient and not only wastes more energy starting the engine, but also wastes more energy when being charged and you'll see your carefully researched (ha!) rule of thumb is complete nonsense.

Don't swiss vehicles spend a lot of time at high altitude? If you've ever driven at high altitude you'll know that engines are harder to start there too. My advice is that should you stop at the top of the Stelvio pass to take a photo, do not switch off the engine of your aging Beetle.

Re : Re: Rule of thumb

And now I've finished breakfast ...

The very conservative estimate for the energy to start an engine I gave above is equivalent to 0.5 grammes of diesel (~45MJ/kg). Even allowing for inefficiencies that's still a tiny amount.

My guess is any starting problems encountered on the passes where the result of a hot petrol engine evaporating the petrol in the carburettor at the low atm, pressure

@Grease Monkey

True the book is always better than the movie. But that image of Charlton Heston in the end?

Now that was classic.

Its funny that my post got thumbs down when you consider that the only people who buy hybrids do so for the smugness effect (Ok you need to know your South Park)

The irony is that as the western nations spend more money reducing their emissions, the nations like China and India are increasing their CO2 and waste output. So yeah its cheaper to do business in these nations.

But the points I made earlier in my post still stand. In the US, there's the mentality of "nobody but a nobody walks in LA..."... that is to say, you want your freedom so you want your wheels. You want your single family home with your white picket suburban fenced in dream. All inefficient.

You want to cut down on green house gas emissions, look at urban living and being able to walk to work, shopping, etc ...

But lets not rush things. Lets take our time and come up with a more fuel efficient replacement to our car...

Nice calculation but

The trip computer says my car is using something like 0.3l per hour at tick over, so idling for a few minutes is not that big a deal.

I think this whole issue of cars and CO2 is a bit of a dead end. Improving mpg is very good but it seems to me that governments are keen on us concentrating here so that we don't stop and look at other much bigger polluters.

Finlay, if you consider that a modern family diesel will do at least double the mpg of an early Cortina, for example, despite weighing almost twice as much (I know it varies, but it is a lot more) then think what we could achieve if we gave up some of our safety features.... just a thought.

Dop cars

still use carburettors ?

Fuel injected ones have no carburettors !

Re : Dop cars still use carburettors ?

Old ones do and Grease Monkey said "My advice is that should you stop at the top of the Stelvio pass to take a photo, do not switch off the engine of your aging Beetle"

Fair enough points

You do need to compare like for like. That would either include the feed stock to the refinery (and distribution to fuel pumps) or exclude the feedstock to the power-plant.

I would hazard a guess that if you look at the entire production chain things probably even out somewhat once you take into account mining of coal, construction of hydro-dams and oil rigs and the whole fun and games of nuclear.

biased links?

You mean like the links you haven't provided at all...

It's nearly free

"""The environmental impact of the production of the diesel fuel at source (refinery)"""

Unless you presume that we cease all oil refining, then diesel will be produced, since it exists in all crudes, to some extent. If we stop driving diesel vehicles and can't use our diesel for similar purposes (Heating Oil, Kerosene, Jet Fuel,) then it'll just have to be stored somewhere, or put through energy-intensive processes to crack it down to gasoline or something.

"""And how about all the other factors such as exploration, extraction, shipping etc. There have been studies done on this, and from memory petrol and diesel end up looking pretty poor, but I'm sure there will be plenty of biased links supplied below."""

Those are pretty well documented as being a tiny, tiny fraction of the energy contained in the fuel. There are some US DoE studies of what amounts of an energy profit ratio of various energy sources (How many joules (or BTU, probably...) does it take to get one kj of fuel,) which I'll allow everyone to find for themselves, because I don't have the patience to navigate their messy website right now. In any case, crude oil is one of the lease energy-intensive ways to get any sort of fuel, and the DoE is nothing if not thorough in their research.

Well...

Diesel is a mixture of various petroleum products and not a specific individual refinery product.

I can mix vegetable oil and petrol together and run a diesel on it....and even run it on straight veggie oil ! (66p/litre at Tesco (special offer))

Re : can mix vegetable oil and petrol together and run a diesel on it

Unless it's a very old and cheap diesel it wouldn't be recommended.

http://www.vegetableoildiesel.co.uk/introduction.html

1. May cause engine coking if misused.

2. May invalidate vehicle warrantee.

3. Exhaust smells of chips (unless cat. converter fitted).

4. Have to pay tax to customs and excise

5. Harder to start the engine in the morning

6. Will destroy some injector pumps

7. Only useful in older vehicles.

FAIL

"I'd buy an electric car just to poke a finger in the collective eye of the despots who own all the petroleum."

Oh noes! Whatever will they do? Oh, wait, it turns out that they also own all the coal and gas (and oil) that's burned in the power stations that are making the electricity for your clownmobile.

If it looks like you're paying them less for electricity, you're not - most of the money we pay on petrol or diesel goes to Revenue Retrieval anyway, not the Houses of Saud and Bush.

The only way to stick it to the despots is to get on your bicycle, or better yet, top yourself. That'll show 'em.

Read much?

"""Then for most vehicle classes, electric vehicles are cleaner even if the power is produced by gas / oil at the power station."""

The report considered electricity made from all non-renewable sources, presumably in ratios typically found in various first world countries. And you typically can't choose to just have the cleaner fossil-derived electricty delivered to your home / wherever you charge your car.

Handy to dismiss an entire report with a single sentence though.

Battery Cost

Actually the wear and tear on EV batteries is greater than the cost of gasoline or diesel. Teasing one to focus only on the cost of electricity is a diversion from the greater costs.

Re: but

Typical replacement interval for the battery packs seems to be on the order of every 50 000 miles. And you can expect that to be some several thousand UKP to do. Estimates waved around for US models have been on the order of $5000-8000. Amusingly, this is roughly the premium for hybrid/electrics over chemically-powered vehicles in the base price for similar vehicles.

Bah!

Battery replacement?

(Dons turban, places fingertips on temples and closes eyes)

About every five years, on average, at best.

Y'know, LION batteries have been known to have exciting behaviour under low-charge conditions. Let's hope there won't be any Orbital iPhone moments with LION powered leccies.

Quite often

Lithium ion batteries are always oxidising. Probably get 5 years out of them before the capacity starts to diminish.

Also, what is the safety like? Lithium ion batteries can explode if damaged or overheated.

Or discharged too deeply/too quickly.

Can you say "exothermic"?

I think the rule of thumb for most li* batteries is 1000 charge/discharge cycles. Much less if you're putting them under a high load. Either they need to get very cheap, or a hydrogen infrastructure needs to be built. As I mentioned above, electric vehicles can be incredibly high performance, but while battery tech has improved massively in the last few years it's still not going to get you 500 miles on one five-minute charge.

Fuel cells, however, can.

Fuel cells

"I think the rule of thumb for most li* batteries is 1000 charge/discharge cycles. "

I thought it was more like 400, with the higher quality ones reaching 600-ish.

"Fuel cells, however, can."

On the other hand - how many billions of dollars/pounds/euros would it cost to build a hydrogen infrastructure covering the entire country? By some studies, if electrical vehicles are only charged at night - when the electrical grid/infrastructure has very little use - the current generation and distribution capacity would cover close to 20% of cars on the road with no augmentation. That is a heck of an argument to consider when comparing hydrogen to electric from the point of view of the generation and distribution facilities.

Prius 2004

Battery life 100,000 miles (160,000 KM) or 8 years.