But even if you aren't Iron Man, there are companies ready and waiting to 'eco-mod' the classic of your dreams. William Scholes introduces three of Drive's favourites, one of which is even vaguely affordable...

1. Lunaz Bentley S2 Continental

Silverstone-based outfit Lunaz are establishing themselves as the Rolls-Royce of classic electric conversions, not least because they have already worked their nuts-and-volts magic on some of the most elegant automobiles built by the marque.

Their 1961 Rolls-Royce Phantom conversion is stunningly executed with a fanatical attention to detail.

I prefer this, however. Also from 1961, it's an exquisite Bentley S2 Continental. Lunaz remove the original 6.2-litre V8 engine and slip in an electric motor, good for 400bhp and 530lb ft of torque. Ideal for wafting around, but brisk too, with a sub-7 seconds 0-62mph time.

Lunaz say their mission is "to further the legacies of the most beautiful cars in the world" by making "these iconic machines a relevant and usable proposition for the 21st century".

Expect to pay at least £350,000 for one of these beautiful cars.

2. Inverted Range Rover

Joining the long queue for the Sprucefield rapid charger in your Lunaz Rolls-Royce or Bentley might seem a trifle undignified, but if you had a classic Range Rover - positively dainty compared to today's behemoth of the same name - at your disposal you might even be tempted to whizz through the McDonald's drive-through for a McFlurry and milk shake.

Step forward 'EV regeneration specialist' Inverted, who offer just that. They take out the Range Rover's original V8 and fuel tank and wire in a 80kWh Tesla battery and motor. It serves up 450bhp and 443lb ft of torque, which represents a big boost from the 125bhp and 185lb ft the car had to make do with in 1970.

You get new axles and brakes to cope with the more powerful drivetrain, not to mention the 0-60mph time of 5.0 seconds.

As well as feeling a bit more usable than a Lunaz Rolls-Royce or Bentley, the Inverted Range Rover is also cheaper. Not by much though - we're in £225,000 'plus VAT' territory...

3. Electrogenic Mini

For a more affordable route to an electrified classic, try Electrogenic's 'plug and play' kit for the venerable Mini.

It costs £15,000 plus VAT, to which you'll have to add the price of an old Mini. As with many other British classics, prices have crept up - have you seen how much an old Land Rover Defender is now? - but it means you could get an electric 'old' Mini for much the same £30k BMW asks for an electric 'new' Mini.

Classics are appreciating assets, so going old-school could be a shrewd move. According to Electrogenic fitting their kit 'simply' involves removing the Mini's front subframe and engine assembly, and bolting in a new subframe already fitted with an electric motor and battery.

"The installer simply bolts in the new subframe assembly and wires up the throttle and dashboard – that’s it," explain Electrogenic.

"The charging socket is also incorporated neatly into the new subframe assembly, so there’s no high-voltage wiring at all."

The motor produces 60bhp and 100lb ft of torque, which ought to be plenty enough to retain the Mini's trademark nippiness. The battery is a 20kWh unit, said to be good enough for around 80 miles of range.