This case study presents a detailed analysis of the power delivery solutions implemented for tethered remote operated vehicles (ROVs). The document outlines the challenges faced by these vehicles, particularly the need for a reliable and efficient power supply system. It describes the Vicor solution, which includes high-voltage, fixed-ratio bus converter modules and Zero Voltage Switching (ZVS) buck regulators. The power delivery network is designed to optimize power through the tether while minimizing size and weight. The study highlights the key goals of optimizing power delivery, ensuring high reliability, and efficiently converting high voltage to safe 48V SELV. The Vicor BCM® modules achieve up to 98% efficiency, significantly reducing tether size and drag, thus extending operational time underwater. The integration of the BCM4414 modules facilitates the conversion of power from ground stations to the ROV, ensuring maximum efficiency and flexibility in power management. This case study serves as a comprehensive guide for understanding the power requirements and solutions for tethered ROVs.