UAE Puma Defender EV with 100 kWh Tesla Battery and Active Cooling

Client goal

The problem to solve

Create a left-hand-drive electric Defender suitable for UAE conditions, with the performance and usability of a modern EV while retaining the character of the original vehicle. The conversion needed to feel complete rather than like a collection of aftermarket EV parts.

The brief

What VASS was asked to do

Electrify the vehicle, integrate a large OEM EV battery pack, uprate the drivetrain, retain a high-quality cabin experience, develop OEM-style driver controls and engineer a cooling system capable of supporting cabin comfort and battery temperature control in extreme heat.

Scope of work

Defined engineering work

• Tesla Model S/X 100 kWh battery pack integration
• Tesla Model 3 motor kit installation and EV drivetrain commissioning
• Drivetrain upgrades including limited-slip differentials
• Range Rover gear selector electronics and EV interface development
• Custom centre console integration
• Original Defender gauge cluster reverse engineering and EV functionality development
• Cabin AC refurbishment and evaporator upgrade
• Dual electric AC compressor system for cabin and battery cooling
• Tesla-style battery chiller/heat exchanger integration
• Custom HVAC and cooling controller development
• Pressure, temperature and compressor monitoring
• 50 C static heat-soak testing in a paint booth

Key systems

Systems involved

• 100 kWh Tesla Model S/X battery pack
• Tesla Model 3 motor package
• Custom EV control electronics
• Range Rover gear selector interface
• Reverse-engineered Defender gauge cluster
• Dual electric AC compressors
• Battery coolant chiller circuit
• Two full-size condensers
• Large motor cooling radiator
• High-power electric cooling fans
• Sensor-based HVAC and cooling safety logic

Engineering challenge

What needed careful resolution

• Packaging a large EV system into a Puma Defender while keeping the vehicle usable and serviceable
• Making the conversion feel like a factory-quality EV rather than an aftermarket retrofit
• Managing battery and cabin temperature for UAE-style heat
• Modernising the original heater and AC controls without losing the Defender interior feel
• Reverse engineering the gauge cluster so original visual parts could be retained
• Integrating an OEM Range Rover selector with the EV control system

Practical outcome

The result

The vehicle became one of the most complete and factory-feeling EV Defender projects VASS worked on. The EV drivetrain, selector, gauges, cabin AC and active battery cooling were developed into a coherent system, then tested in a 50 C heat-soak environment to prove the cooling strategy under difficult static conditions.