Case Study: Healthcare

Health City at Camana Bay is a 70,000‑square‑foot high‑acuity medical facility that specializes in cancer-care, neonatal-care, cardiology, neurology and robotic surgery. These high dependency treatments and services depend on continuous, stable electrical supply to operate life‑support systems, diagnostic equipment, surgical platforms and environmental controls 365 days a year.

Although the Cayman Islands maintains a modern and reliable electrical grid, unplanned outages can still occur due to severe weather, equipment faults or external incidents. Even short duration interruptions can cause voltage instability, equipment shutdowns and loss of critical clinical functionality.

To maintain compliance with life-safety and critical-power standards, Health City required a resilient backup power system capable of rapid response during utility loss, ensuring continuous operation of all mission-critical loads without disruption while supporting the hospital's critical-load profile.

Rehlko and its authorized distributor partner in the Cayman Islands, Corporate Electric, were selected to design, manufacture, install, commission, and support the backup power system for Health City hospital.

The solution consists of three 500 kW Rehlko generators connected in parallel by synchronization controller, providing 1.5 MW of installed capacity. This multiunit configuration enables dynamic load sharing, operational flexibility, and increased resilience during maintenance or unplanned outages. This architecture supports both Block A and Block B distribution networks, delivering N+1 redundancy and stable operation even in the event of a single generator failure.

The generators are controlled by the intuitive APM603 controller, which provides automatic start on mains failure, real-time synchronization, isochronous load sharing, and precise voltage and frequency regulation across the paralleled system. A dedicated paralleling switchboard with integrated circuit breakers provides system protection, selective coordination, and stable power delivery to sensitive medical loads. The APM603 also supports event logging, alarm management, and remote monitoring, giving operators comprehensive visibility into system status and performance.

The installation includes a network of automatic transfer switches (ATS), including a 2,600-amp unit and an additional 260-amp unit. These ATS continuously monitor utility conditions and automatically transfer critical loads to generator power during outages. Programmed transition and bypass isolation capabilities allow maintenance without interrupting essential services.

Each generator is housed in marine grade, corrosion‑resistant acoustic enclosures, delivering 92.9 dB(A) at 23 ft. The canopies provide robust outdoor-rated ingress protection. Designed for high humidity and salinity, the enclosures are fully suited to Caribbean environmental conditions. Given the region’s exposure to hurricanes, the canopies are certified for ±65 psf wind pressure, ensuring structural integrity under extreme weather. The installation is complemented by NEMA 3R outdoor‑rated panels with IBC‑compliant seismic resistance.

The installation also incorporates extended-runtime fuel storage, with each generator mounted on a UL-listed 894-gallon sub-base tank capable of supporting approximately 24 hours of operation at full load. Integrated leak detection, fuel polishing, and automatic refueling interfaces help optimize fuel quality, environmental safety, and operational readiness during prolonged power disruptions by limiting manual intervention.

The solution was successfully commissioned to meet rigorous healthcare and emergency power requirements, including NFPA 110 for Emergency and Standby Power Systems and NEC Article 700 for emergency electrical systems. Designed in alignment with the Cayman Islands Building Code and the International Building Code (IBC), the installation delivers the safety, reliability, and performance required in mission-critical healthcare environments.

In the event of a grid outage, the integrated Automatic Transfer Switch (ATS) infrastructure seamlessly transfers essential loads to generator power, ensuring continuous electrical service to critical systems, including operating rooms, surgical robotics, diagnostic imaging equipment, emergency lighting, HVAC systems serving critical care and isolation areas, medical IT infrastructure, and nurse-call systems.

The parallel generator configuration provides N+1 redundancy, allowing essential operations to continue even if one generator is offline for maintenance or an unexpected event. This architecture enhances system availability while providing greater operational flexibility for facility management teams.

Delivered by Rehlko, in partnership with local distributor Corporate Electric, the project demonstrates how redundant power generation, intelligent synchronization controls, advanced transfer switching, and a robust electrical distribution network can support the demanding requirements of modern healthcare facilities. The result is a resilient backup power solution that helps protect critical equipment, maintain operational continuity, and support uninterrupted patient care during utility disruptions and severe weather events.