The gorgeous 1929 Rolls-Royce Phantom II that Electrogenic, a globally recognised British EV technology firm, recently converted to clean, all-electric power, was finished for a very special customer: Jason Momoa, the star of Dune, Game of Thrones, and Aquaman.

Momoa's documentary series On The Roam, currently streaming on HBO Max and Discovery+, features an all-electric Phantom and the gifted engineers and fabricators of Electrogenic. The show centres on Momoa, who travels the globe and meets remarkable people who are forging their own creative pathways. These people include singers, sportsmen, and craftspeople, as well as motorbike builders.

The laborious process of converting the amazing Rolls-Royce Phantom II, which has original coachwork by HJ Mulliner & Co., to electric propulsion is depicted in On The Roam. Working closely with Momoa, an environmentalist and car enthusiast, Electrogenic has provided the stately Phantom II with the smooth, silent powertrain that Sir Henry Royce and Charles Rolls, two of the early pioneers of electric motor technology, may have selected had the technology been available to them.

Jason Momoa, said: “In order to pull off this dream project, I had to find the right partner. I needed a team that would appreciate the stored history of this car while updating its technology. Electrogenic is all about honouring vintage cars. Making them electric without losing any of the vehicle’s character. They were the perfect fit.”

Steve Drummond, Director, Electrogenic, added: “We’re delighted to finally reveal the full details of this car to the world. It has been a labour of love for everyone at Electrogenic, and a lot of fun, working with Jason over the course of 18 months to bring his vision to life.

“Our team of engineers, programmers, and fabricators have poured their hearts and souls into Jason’s beautiful Phantom II. This is undoubtedly the most complex classic car EV conversion ever undertaken, so the stunning results really are a testament to the world-leading talents of our team. We’re immensely proud of the finished car, and humbled that Jason entrusted us with this landmark project.

“Now, for our work and team to be showcased on screen by Jason alongside other passionate craftspeople, really is the icing on the cake. It’s the perfect way to celebrate this Phantom II, which is now future-proofed for another hundred years of stately motoring.”

Electrogenic, also famed for its range of revolutionary, award winning, ‘drop-in’ EV conversion kits for popular models—offered in the UK, USA, and beyond by its partner-installer network—has sympathetically modernised this jewel of British automotive history. The 1929 Phantom II now packs a whisper-quiet, effortlessly powerful electric powertrain, featuring Electrogenic’s proprietary EV technology. The Phantom’s sublime original aesthetics and timeless features are retained, and as with all of Electrogenic’s projects, the conversion is entirely reversible.

The car was originally powered by a gargantuan 7.7-litre pushrod straight-six engine, producing between 40 and 50 bhp, bolted directly to a four-speed, non-synchromesh manual gearbox. In standard configuration, Rolls-Royce claimed a top speed of ‘well over 80mph’. Now, the petrol engine and gearbox have been carefully removed and replaced by 93 kWh of batteries, which have been precision-integrated into the existing structure of the car.

The batteries feed an electric motor mounted between the chassis rails via a custom single-speed direct drive transmission, channelling 150kW and 310Nm of torque to a fixed reduction gear, which in turn delivers 1,000Nm to the prop shaft. The systems are all seamlessly linked and managed by a bespoke suite of software, all developed in-house by Electrogenic’s engineers.

Electrogenic - Jason Momoa electric Rolls - On The Roam

As with every Electrogenic conversion, the battery configuration has been tailored specifically to the model in question; all are housed within the car’s original architecture, no modifications are made to the structure itself. This is made possible thanks to Electrogenic’s world-leading battery system design capabilities.

In the case of the Phantom II, Electrogenic installed the batteries under the hood and between the chassis rails, taking advantage of the significant space that the engine and gearbox occupied.

The batteries themselves are housed beneath a gleaming, hand-formed, and hand-riveted aluminium cowling—a sculptural design element that delights every time Phantom’s centrally hinged bonnet is raised.

The battery installation and ornate cowling perfectly illustrate the Electrogenic team’s ability to deliver a fully sympathetic re-engineering that combines cutting-edge technology and innovation with show-stopping design flair.

Naturally, there were a number of challenges associated with sympathetically converting a near century-old, idiosyncratic luxury motor car to run on the latest EV technology. Electrogenic has used its deep reserves of engineering expertise and resourceful creativity to deftly solve them.

One key challenge was devising a way to preserve and update the Phantom’s centralised, entirely mechanical, ‘through-flow’ chassis lubrication system. This system was designed to send oil to the car’s many phosphor-bronze bushes for brake and suspension linkages, as well as other mechanical control systems—crucial to the Rolls-Royce trademark silken drive.

As foreseen, the complex system was disrupted by the removal of the straight-six engine, however, Electrogenic supplemented its design to ensure it continued to work as intended.

Creating a new cable-operated braking system that would function flawlessly with the revised EV architecture was another difficulty they had to accomplish. The big battery pack now occupies the space where the original brake pedal and levers were located, and the braking servo was contained in the gearbox, which has been removed. The team repositioned the original brake levers and cables, even keeping the same mechanical balancing system ratios, but in a different arrangement, as a way to embody Electrogenic's basic conviction in imaginatively retaining the character of each automobile it works on.

A newly fitted hydraulic system between the pedal and the original cable actuators greatly increases the braking power of the redesigned pedal, which operates the brakes. To further improve braking performance and increase economy and range, the Electrogenic team adjusted the brakes to work in tandem with the motor's energy regeneration feature.

The brake system exemplifies Electrogenic at its best: skillfully fusing new and ancient technologies to perform harmoniously, maintaining original characteristics and character where feasible while transforming functionality, usability, and compatibility with the surroundings.

Electrogenic - Jason-Momoa electric Rolls-Royce Charging

Inside, Electrogenic has kept the lovely original details of the exquisite leather and wood-lined cabin while carrying out a sensitive upgrade programme. Both the regular gauges and the original controls have been cleverly adapted. Originally a vertical sight glass, the gasoline gauge is currently a state-of-charge LED gauge. With the ability to display power harvesting during regeneration and the rate of power draw during acceleration, the amp metre has evolved into a power gauge. The water temperature gauge now indicates the electric motor's temperature, while the oil temperature gauge now displays the charger's temperature.

The music equipment in Momoa's automobile has also been updated: a top-of-the-line, multi-speaker HiFi system with an integrated subwoofer and complete Bluetooth connectivity is now housed in the cabin. Everything about this is subtly concealed from view.

Every conversion is a reflection of Electrogenic's strategy of creating and producing its own technology, which includes digital dashboards, printed circuit boards (PCBs), software developed internally, and vehicle management systems capable of integrating any type of motor or battery module to provide the newest innovations in technology into its conversion packages.

The modifications make use of incredibly small in-line and transverse reduction gearbox systems, as well as extremely inventive mechanical components made in the UK, such as a special method for producing high-density battery packs. The existing structure and architecture of the original vehicles are always intact, thanks to the expertly packed changes. This method guarantees the complete reversibility of all electrogenic transformations.