Clean Compressed Air for Smart Medical Air Systems

For air compressor companies, transitioning from a traditional role as a “equipment supplier” to a “comprehensive energy service solution provider” is key to opening up the high-end market and enhancing customer loyalty. The smart hospital energy-saving market is vast, and by combining mature air compressor energy-saving technology with innovative energy storage concepts, companies can not only create tangible value for their clients but also contribute to sustainable social development, providing the best value-added service.

Hospitals, as major energy consumers operating 24/7, face significant pressure in managing energy costs. While lighting and air conditioning energy savings are common, a frequently overlooked yet promising area is the medical air system.

This article explores how to provide a practical, measurable energy-saving value-added service for smart hospitals through a combination of “SIND Air Compressor System Optimisation + Energy Storage Technology.”

A company’s value-added service is no longer simply selling a “highly efficient” air compressor, but providing a systemic solution.

• Basic Optimisation – Lean Management of the Air Compressor System
• Value-Added Core – Coupling Energy Storage Systems to Achieve “Peak Shaving and Valley Filling”

Module One: Basic Optimisation – Lean Management of the Air Compressor System

• Equipment Replacement: Replace old fixed-frequency air compressors with permanent-magnet variable-frequency air compressors, which have extremely high partial load efficiency and can perfectly adapt to fluctuating air demand.
• Pipe Network Optimisation: Inspect and repair leakage points (a 1mm leak can result in tens of thousands of yuan in losses annually), optimise pipeline layout, and reduce pressure loss.
• Heat Recovery: Recover the thermal energy generated by the air compressors for hot water preparation, winter heating, or sterilization of surgical room water, directly saving on boiler gas or electricity costs.

Module Two: Value-Added Core – Coupling Energy Storage Systems to Achieve “Peak Shaving and Valley Filling”

• Technical Principle: Add a compressed air energy storage system (or a cluster of high-pressure storage tanks) within the air compressor station. This system essentially functions as a massive “air battery.”
• How does it work?
• Valley Filling (Energy Storage): During off-peak hours at night (or when the hospital’s overall electricity load is low), the air compressors run at full capacity, storing excess compressed air in the energy storage system.
• Peak Shaving (Energy Release): During peak hours during the day (or when surgeries are concentrated and electricity demand is high), the air compressors prioritise using the compressed air stored in the energy storage system, and may even completely shut down, with the energy storage system supplying the air. This avoids starting large power air compressors during peak hours.
• The core value it brings:
• Significantly lower electricity costs: More electricity is used during off-peak hours.
• Precise control of “maximum demand”: Avoiding the impact of large power air compressors starting during peak hours on the grid, effectively flattening the peak electricity usage, thereby reducing the monthly basic electricity fee. This is the largest energy-saving benefit.
• Enhanced system reliability: The large energy storage capacity acts as a highly stable buffer air source. In the event of a sudden power outage or air compressor failure, it can provide a critical department with an emergency air source for up to 40 minutes, giving maintenance personnel valuable time to repair the system, thus enhancing medical safety.

Energy-saving renovation of a tertiary hospital

• Project Background: A tertiary hospital in East China, with three 110kW fixed-frequency air compressors in the air compressor station (two in use, one as backup), annual electricity costs of approximately 1.2 million yuan (CN¥1,200,000, about US$169,014), and high demand values, resulting in high monthly basic electricity fees.
• Renovation Plan:
• Basic Optimisation: Replace two 110kW permanent-magnet variable-frequency air compressors (one in use, one as backup) and install a heat recovery system for hot water in the staff bath.
• Value-Added Service: Add a 20-cubic-meter high-pressure energy storage tank group and an intelligent control system.
• Intelligent Control Strategy: The system is connected to the hospital’s local network, providing real-time monitoring of the total power consumption and electricity price periods across the hospital.
• Off-peak hours (23:00-07:00): The energy storage system charges air at full capacity, filling the pressure.
• Peak hours: Prioritise using the energy storage tanks for air supply, with the variable-frequency air compressors only running at low power to top up when pressure is insufficient.
• Real-time monitoring of the total power consumption across the hospital. When the system predicts that the five-minute average power will exceed the maximum demand setting, it will intelligently limit the start-up and power of the air compressors to ensure that the limit is not exceeded.
• Benefit Analysis (Annualized):
• Electricity Savings: Due to the replacement with variable-frequency compressors and the peak shaving and valley filling of the energy storage system, the overall electricity savings rate is 32%, saving approximately 384,000 yuan in electricity costs annually (CN¥384,000, about US$54,084).
• Basic Electricity Fee Savings: The maximum demand value is reduced by 50kW, saving approximately 15,000 yuan in basic electricity fees monthly (CN¥15,000, about US$2,112), or 180,000 yuan annually (CN¥180,000, about US$25,352).
• Heat Recovery Savings: Annual savings in gas costs are approximately 80,000 yuan (CN¥80,000, about US$11,267).
• Overall Benefits: The total annual savings are approximately 644,000 yuan (CN¥644,000, about US$90,704). The total project investment is approximately 1.5 million yuan (CN¥1,500,000, about US$211,267), with a payback period of less than 2.5 years.
• Hidden Benefits: The system provides more stable air supply pressure, earning high praise from the hospital administration; the emergency backup air source time is extended to 40 minutes, earning praise from the security department.