Land Rover Defender owners keen to give their diesel runaround an electric makeover now have the option of an affordable “drop-in” conversion kit.

Unlike bespoke modifications that can run to well over £50,000, the package designed by Oxfordshire firm Electrogenic has a guide price of £24,000.

This has been achieved by designing the kit so that is slots into the engine bay, without the need to carry out any expensive fabrication work. The electric drive motor simply bolts to the Defender’s existing bell housing, retaining the original gearbox, transfer case, axles and diffs.

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Other cost-saving measures include keeping power at sensible levels and fitting modest battery packs with just enough output to satisfy the needs of a typical farm vehicle.

That said, with 120bhp and 235Nm torque on tap, performance figures are comparable to that of the original diesel engine. The nature of electric motors means peak torque is available from the off, so it should be quick off the mark with heavy loads in tow. Dual-stage regenerative braking also allows for controlled descending and deceleration without the need to use the brakes.

Range from the 52kWh battery pack is just over 100 miles when cruising on tarmac and considerably higher when hacking about at slower speeds off road. Towing heavy loads will drain the charge a little quicker, but the firm says the reduction in range isn’t dramatic. Estimated battery lifespan is 200,000 miles or more, which means most owners should get many years’ worth of driving out of them.

As standard, the kit comes with a 7.5kW AC charger that’s designed to replenish the batteries overnight. However, faster options can be added at additional cost.

Electrogenic has been testing converted vehicles on Worthy Farm in Somerset, host to Glastonbury Festival, for the past 18 months and kits will soon be available to order, ready for deliver from October.

Initially, these will need to be installed by approved mechanics, but the firm might offer them as a DIY kit in the future. Versions for series Land Rover models are also in the pipeline.