Medical Support Innovation with the AlphaESS TB125

Delivering Off-Grid Power for Mobile CT & MRI Diagnostic Units across the UK with our TB125

Powering Mobile Healthcare with Reliable Off-Grid Energy Storage

Quest Power is transforming mobile healthcare across the UK by deploying a reliable, cost-effective energy solution to support CT and MRI diagnostic units that bring life-saving medical imaging directly to hospitals and communities.

To Power these highly specialised mobile facilities, Quest Power required an energy solution capable of delivering the stability, responsiveness and reliability demanded by sensitive medical equipment – while reducing reliance on diesel generators.

In a tri-party collaboration led by Quest Power, Immersa and AlphaESS UK developed a bespoke off-grid energy storage solution centred around the AlphaESS TB125 and 300K-STS commercial battery platform. Following extensive research, product development and real-world testing alongside AlphaESS UK engineers, Quest Power committed to deploying 18 systems totalling 2.25MW / 4.698MWh of combined capacity, supporting one of the UK’s most innovative applications of commercial battery storage.

A Groundbreaking Energy Solution for Mobile Medical Imaging

DISCOVER THE PROJECT AT A GLANCE

Customer: Quest Power
Application: Mobile CT & MRI diagnostic facilities
Supplier and support partner: Immersa

Battery Storage system: AlphaESS TB125 and 300K-STS
Battery Capacity: 261.2 kWh per system
Battery Inverter Rating: 125kW
Transfer Switch for Off-Grid: AlphaESS 300kVA STS
Deployment: 18 systems
Total Capacity: 2.25MW / 4.698MWh

By working closely with Quest Power and AlphaESS UK, Immersa helped deliver one of the UK's largest off grid commercial battery deployments for the healthcare sector. The result is an innovative, scalable energy solution that improves operational efficiency, reduces emissions and provides dependable power for life-saving diagnostic services.

Immersa

The Challenge — Mobile CT and MRI scanners present one of the most demanding off-grid power applications.

Unlike conventional electrical loads, medical imaging equipment requires an exceptionally stable electrical supply with tight voltage and frequency tolerances that vary by CT and MR OEM. During scanning, the equipment can also generate rapid, high transient power demands that conventional diesel generators struggle to accommodate efficiently.

Quest Power needed a solution that could:

Deliver quality power in completely off-grid environments
Support rapid fluctuations in demand from CT and MRI scanners
Integrate and control diesel generators for seamless power switches and overnight battery charging
Improve fuel efficiency and reduce diesel consumption and emissions
Lower operating costs for CT and MRI businesses across the UK
Maintain maximum reliability for critical healthcare services

The solution needed to be robust enough for continuous operation within the mobile diagnostic units deployed throughout the UK.

Layer 2 Quest

Layer 3 Quest

Layer 4 Quest

The Solution — Delivering Robust Energy for Mobile CT and MRI Units

AlphaESS UK and Immersa worked closely with Quest Power to design a purpose-built battery energy storage architecture to meet their requirements.
At the heart of each system is the AlphaESS TB125 (125kW / 261kWh) commercial battery, integrated with a 300kVA Static Transfer Switch (STS) for intelligent generator controls. Rather than operating as a conventional generator-backed-up battery, the system is designed so that the battery provides the primary power source for scanning daily.

When the batteries stage of charge (SoC) reaches a predefined threshold, the diesel generator automatically starts, recharges the battery to 100% SoC, and supplies overnight loads before the battery begins discharging again. The intelligent operating strategy dramatically reduces unnecessary generator run-time while ensuring uninterrupted power availability.

Extensive research and development (R&D) was undertaken before commercial deployment, ensuring the system worked effectively and reliability before field deployments.

Why the AlphaESS TB125 and 300K-STS?

Designed for Off-Grid Operation
With 125kW of output power and 261kWh of capacity, the TB125 provides sufficient capacity to meet the majority of the mobile unit’s daily energy demand, allowing the battery to serve as the primary power source rather than the generators. Its intelligent integration strategy establishes control of the diesel generator to support efficient recharge, reduced emissions and operational costs.
Mission Critical Power Stability
Medical CT and MRI scanners require an exceptionally stable power supply. Its standard 125kW output can support 137.5kW output (110% overrated) for short period, ensuring it can deliver fast, high power when its load suddenly increases for intensive scans. The addition of the 300kVA STS ensures seamless transfer between the battery and generator, maintaining uninterrupted operation for sensitive diagnostic equipment.
All-In-One Solution
The TB125 is a fully integrated, all-in-one product. Within the IP55 cabinet, the system contains modules, an inverter, an HV Box, an EMS, a fire suppression system and HVAC. This complete integration improves simplicity, safety and reliability.

More than a battery supplier

A development partner from concept to deployment

Beyond the battery supply, AlphaESS UK and Immersa worked alongside Quest Power throughout the entire development process to create a solution engineered for mobile healthcare applications.

The project involved extensive collaboration, technical development and real-world validation to ensure the solution could reliably power highly sensitive CT and MRI equipment in off-grid environments. Together, the teams developed, tested and refined every aspect of the system for deployment, creating a solution that has now become the foundation of Quest Power’s expanding mobile diagnostic fleet.

Comprehensive Application Testing
Extensive testing was carried out during multiple CT and MRI scanner platforms to validate system performance under real operating conditions. This ensured the battery system consistently delivered the required voltage stability, frequency and rapid power response.
Bespoke Software Development
Working closely with Quest Power, AlphaESS UK engineers implemented software enhancements and Energy Management System (EMS) upgrades to optimise the battery operation, generator integration and overall system performance. The control system continues to evolve as additional systems are deployed.
Commissioning & Technical Expertise
AlphaESS UK provided hands-on commissioning support, technical guidance and application engineering throughout the project. Close collaboration during installation and commissioning ensured each system performed exactly as intended before entering service.
Product Training
AlphaESS UK engineers carried out extensive on-site training for Quest Power’s logistics and electrical engineering team. This training program was designed to enhance Quest Power’s knowledge of the product and Alpha Cloud, whilst guiding them on how to conduct their own operation and maintenance of the system.

The Results — Powering Innovative Life-Saving Diagnostics Across the UK

The project has demonstrated how commercial battery storage can successfully replace diesel generators as the primary power source for mobile healthcare applications.

Following successful validation, Quest Power committed to deploying 18 AlphaESS battery systems, representing 2.25MW / 4.698MWh of installed battery capacity, with systems already operating across the UK.

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INSTALLED BATTERY CAPACITY

Key outcomes include:

Reduced diesel generator operating hours
Improved fuel efficiency
Lower emissions
Stable power for mobile CT and MRI scanners
Improved operational reliability
Reduced operating costs
Scalable solution for future fleet expansion

Perhaps most importantly, the project enables mobile diagnostic units to continue supporting earlier diagnosis of lung cancer and other serious health conditions by providing dependable power wherever healthcare services are needed.

LOOKING AHEAD

The partnership between Quest Power, AlphaESS UK and Immersa continues to evolve through ongoing software development, operator training and Energy Management System enhancements.

Future optimisation will focus on further reducing generator runtime, improving operational efficiency and supporting the continued expansion of Quest Power's nationwide mobile healthcare fleet.

As healthcare providers seek cleaner, more resilient energy solutions, this project demonstrates how battery energy storage can play a vital role in delivering both environmental benefits and meaningful societal impact.

Innovation Powered by Collaboration

Discover how AlphaESS UK, Quest Power and Immersa are combining specialist expertise to develop innovative energy storage solutions for complex, real-world applications.

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