Business Mileage Rate - 25p/40p

[Fred Bloggs]

It's green ain't it.

Only if you ignore where the leccy comes from. If you compare the overall efficiency of a leccy car (most probably powered by a coal or a gas fired power station plus the power transmission and charging losses) to a modern turbo diesel, the diesel beats it hands down.

[manclarky]

I've no idea how electric cars are treated for expenses, but the fuel certainly wouldn't be free even if you could do the round trip on a charge.

How you would account for the not inconsiderable electricity cost could get quite complicated.

My understanding of (for example, the Leaf) is that it's about 4p to fully charge the thing for around 100 miles.....I consider that amount inconsiderable

[VectraMan]

Only if you ignore where the leccy comes from. If you compare the overall efficiency of a leccy car (most probably powered by a coal or a gas fired power station plus the power transmission and charging losses) to a modern turbo diesel, the diesel beats it hands down.

My push bike doesn't require leccy.

I think you're wrong about that. Even diesels are very inneficient, and as Clarky says the cost per mile is far less for an electric car.

[TykeMerc]

My understanding of (for example, the Leaf) is that it's about 4p to fully charge the thing for around 100 miles.....I consider that amount inconsiderable

With current (and rising) electricity prices that seems unlikely, but I admit that I've not researched or calculated it myself.

20p/mile if you cycle? That's pretty daft.

[Fred Bloggs]

My push bike doesn't require leccy.

I think you're wrong about that. Even diesels are very inneficient, and as Clarky says the cost per mile is far less for an electric car.

(Without looking up the figures) - A modern turbo diesel should be about 45% thermal efficiency. A modern condensing coal fired power station about 38% before you factor transformer losses, transmission losses, charging losses, vehicle motor and transmission efficiency. I'd guesstimate that an electric vehicle has an overall thermal efficiency approaching about half that of a modern turbo diesel.

[Wanderer]

Even diesels are very inneficient, and as Clarky says the cost per mile is far less for an electric car.

You are confusing the cost of fuel with overall efficiency of operation.

Diesel vehicles pay a lot of money in fuel duty which electric cars don't have to pay so the electric ones are effectively subsidised by the government.

[VectraMan]

(Without looking up the figures) - A modern turbo diesel should be about 45% thermal efficiency. A modern condensing coal fired power station about 38% before you factor transformer losses, transmission losses, charging losses, vehicle motor and transmission efficiency. I'd guesstimate that an electric vehicle has an overall thermal efficiency approaching about half that of a modern turbo diesel.

I'd been told it was more in the range of 30% for diesel (and about 20% for petrol) at best. You have a point about all the charging and distribution losses etc., but I'd still be suprised if a battery car worked out less energy efficient than a diesel. Perhaps you should tell somebody?

[TykeMerc]

I'd been told it was more in the range of 30% for diesel (and about 20% for petrol) at best. You have a point about all the charging and distribution losses etc., but I'd still be suprised if a battery car worked out less energy efficient than a diesel. Perhaps you should tell somebody?

I wouldn't be surprised even when you factor in the energy used in refining and transporting diesel to fuel stations.

Modern diesels are pretty efficient when up to temperature which is probably why most of the worlds goods are transported by diesel powered ships.
Apart from the fuel efficiency issue until someone comes up with a practical method to refuel an electric car in a matter of minutes, the power storage is light and small and the car carries sufficient fuel to cover quite large distances they will remain a non starter.

[Fred Bloggs]

That's right, slow speed marine diesel engine thermal efficiency can reach 50%.

[the_rangdo]

I wouldn't be surprised even when you factor in the energy used in refining and transporting diesel to fuel stations.

Modern diesels are pretty efficient when up to temperature which is probably why most of the worlds goods are transported by diesel powered ships.
Apart from the fuel efficiency issue until someone comes up with a practical method to refuel an electric car in a matter of minutes, the power storage is light and small and the car carries sufficient fuel to cover quite large distances they will remain a non starter.

I reckon most of the worlds shipping uses bunker/heavy oil which is pretty much just the residual carp left over from refining - needs a good while of heating before it can be burnt.