Enfield Thunderbolt

[DaveMiller]

Why would it need a 1.4 engine to charge batteries? Or do you mean the engine kicks in to drive the car and charge batteries when needed?

No, I mean the engine merely charges.   The electric motors are rated at 148 bhp, or 110 kW, so might be using, say, an average of 50 kW on a long journey. The idea is that the car can continue indefinitely (as long as you keep putting petrol in), so you'd need a generator capable of at least 50 kW continuous output - hence the 1.4 litres!

[Bob Purton]

Ah Thanks for the clarification.

Just read up on it, it seams a better compromise that the other type" hybrids" though the makers claim it isn't a hybrid and does proves Stuarts legal argument totally wrong. Sorry Stuart!

[AndrewG]

Why would it need a 1.4 engine to charge batteries?

I think the 'range-extender' function of this engine means that it needs to make enough power for the car to cruise indefinitely at motorway speeds - and that probably needs most of a 1.4, leaving enough surplus to slowly charge the batteries up so that they aren't left in an uncharged condition.

The Ampera type is called a series hybrid since the IC engine is only used in series with the electric motor and cannot be connected mechanically to the drive wheels.  Most other hybrids are parallel hybrids where the IC engine and electric motor can be used in parallel with each other (even if the electric motor is actually on the gearbox output shaft and so mechanical drive has to physically pass along the motor's shaft).

If you want some nightmares about hybrids, one of the prototype 1982 Lucas Hybrids came up for sale recently - imagine having your whole vehicle built by Joseph Lucas, Prince of Darkness.  In this case he would be the Prince of Zero Entropy, since that is the condition of no light and no movement.  And the slightly-RUM connection is that the Lucas Hybrid used a Reliant motor as its range extender.

http://www.sporting-reliants.com/LucasHybrid.htm

And on the title of this thread, I keep reading Titfield Thunderbolt, rather than Enfield.....

[Bob Purton]

I remember that film!

[Nimrod Cabin]

"Can't go yet, Squire's not here"

[Rusty Chrome (Malcolm Parker)]

Great film, I drive past the bridges featured in the opening scene every other day on my way into Bath.

[Nimrod Cabin]

Great film, I drive past the bridges featured in the opening scene every other day on my way into Bath.

Malcolm

You have made me get the DVD out, ah yes! the local Camerton line below and the express S & D above at Midford with 34043 Combe Martin West Country Express en route to Bournemouth West, happy (off topic) days!

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

[marcus]

"But if you buy the railway you can make your own timetable and open the bar"
"Then you can write your own cheque!"

I LOVE that film! "Lion" performs well as the Titfield Thunderbolt", wish she was still running.

I still feel disappointed that a motor is needed to drive a generator to power one or more electric motors, it just seems such a lot of gubbins! I suppose you do get the advantage of having a heater for long drives in winter

[wilksie]

Isn't the Kinetic Energy Recovery System (KERS) a device whereby kinetic energy, harvested during deceleration, is stored as an electric charge which can later be recovered to boost an internal combustion engine? Why should that be prohibited? It wouldn't surprise me if it was taxed, though.

[DaveMiller]

Isn't the Kinetic Energy Recovery System (KERS) a device whereby kinetic energy, harvested during deceleration, is stored as an electric charge which can later be recovered to boost an internal combustion engine? Why should that be prohibited? It wouldn't surprise me if it was taxed, though.

In an electrically-driven car, the recovered energy would be gained by running the motors "backwards" during braking, as dynamos, and would indeed be used for future propulsion.  The KERS in the latest blossoming of "eco" petrol and diesel cars, though, is a bit more subtle:  the charging system is set to provide rather less than the ordinary (starting, lighting, etc) battery would need.  This saves fuel.   When the car is braking, though, it then turns on the (normal) charging system fully, as we won't mind the fact that there's a tiny bit extra of engine braking, and we get a fully-charged battery.

[AndrewG]

Braking regeneration in hybrids is often thought to be a big saving, but I don't think it is.  The Prius is one of the more developed hybrids and I believe braking regeneration recovers less than 10% of the car's kinetic energy.  That's worth having at just the cost of a little control software, but is hardly a game-changer.

KERS is specific Formula 1 technology that doesn't exist elsewhere - and no doubt costs several orders of magnitude more than just burning more fuel!

The intelligent charging system on modern cars is clever, since it too doesn't cost much other than software development.  It also matches the auto-stop-start of many cars, since the energy to restart the non-idling engine would otherwise have been 'wasted' in the brakes.