Delta, a pioneer in power management and smart green solutions, announced its 5,500W 19-inch (1RU) and ORv3 21-inch (1OU) high-power redundant power supplies for AI servers have recently become the world’s first to attain the industry’s highest energy efficiency certification 80 PLUS® Ruby due to their groundbreaking peak efficiency as high as 97.5%, and a power factor of 0.99 under full load.
Delta has drawn upon its superior prowess in soft-switching technology and advanced circuit topology, while also applying third-generation power semiconductor technology to not only surpass the stringent requirements of the 80 PLUS Ruby certification, but also to deliver a 59% increase in power density at 51W/inch³. This 80 PLUS Ruby further cements Delta's technology development.
Energy-efficient power solutions
Mr. Dong Kai, General Manager of Delta Energy System’s Custom Design Business Unit, expressed, "Stable and efficient power supplies are core components of AI servers, playing a crucial role in the operation of AI servers while helping to enhance performance and reduce energy consumption."
He adds, "Delta’s 5,500W high-power redundant power supplies offer an energy efficiency of up to 97.5% and have been already adopted by major global AI companies. This milestone is a testament to Delta’s global leadership in power management and to our long-term commitment to innovation, with a focus on fostering energy-efficient power solutions for the global AI industry."
Requirements for power supplies
Needs for power supplies to reach an energy efficiency of at least 80% across various operating stages
80 PLUS is a well-known international power supply efficiency standard for being significantly higher than most others that many standard power supply unites are applying.
It stipulates requirements for power supplies to reach energy efficiency of at least 80% across various operating stages and is also recognized by both the energy-saving standard ENERGY STAR® of the U.S. Environmental Protection Agency and the EU certification.
Redundant power supplies
Over the past 20 years, 80 PLUS has set six certification levels for internal power supply products, with the highest being Titanium.
In January 2025, the Ruby certification was launched. Regarding the peak power efficiency achieved by redundant power supplies under a 50% load condition, the Titanium standard requires 96%, while the Ruby standard requires 96.5% and a power factor (PF) of at least 0.96. Consequently, Ruby has now replaced Titanium and became the highest tier.
Demand for power supply systems
With the rapid growth of AI, the demand for power supply systems in data centers is becoming increasingly high to handle large amounts of data and complex computations. Delta’s power solutions are responding to the market trends by ceaselessly advancing the boundaries of power products.
Currently, this high-end 5,500W server redundant power supply is designed for AI data centers, offering dual 19-inch (1RU) and 21-inch (1OU) ORV3 standard rack configurations. It supports an input voltage range from 200V to 277V and provides an output power of 5,500W, with an overall conversion efficiency of up to 97.5%.
Delta’s soft-switching technology
In regards to design, this 5,500W server's redundant power supply leverages Delta’s switching technology
According to the 80 PLUS testing report, this product achieves a power factor of 0.99 under full load, which is exceedingly close to the ideal value of 1, proving that most of the electrical energy is efficiently transformed into the computational power required by the data center while minimizing energy losses.
In regards to design, this 5,500W server's redundant power supply leverages Delta’s soft-switching technology and an advanced circuit topology in the Power Factor Correction (PFC) stage, further enhancing overall power efficiency, thermal performance, and optimal conversion.
Third-generation semiconductor power devices
In addition, third-generation semiconductor power devices, such as SiC or GaN, are employed in this advanced power supply, and their superior high-efficiency switching characteristics facilitate the system to operate at higher frequencies, boosting high power density.
Compared to the previous generation 3,000W redundant power supply with a power density of 32W/inch³, the power density of the current 5,500W unit has augmented by nearly 59%, reaching 51W/inch³.
