A cold chain is a series of climate-controlled transport and storage facilities that ensure the viability of testing reagents, medicines, vaccines, and blood products from factory to patient.

Medical refrigerators are used to store many health-care supplies: blood products, vaccines, medicine, and testing reagents. Each has a slightly different chilling requirement. Vaccines are sensitive to both heat and cold and so need to be kept between 2°C and 8°C from the point of manufacture to the point of use. In order to properly store blood and blood products, blood bank refrigerators need to keep internal temperatures between 2°C and 6°C all day, every day. Some vaccines need to stay frozen, so medical freezers must maintain internal temperatures between -15°C  and -50°C . The lack of access to electricity or intermittent power supply in many remote health-care facilities complicate the storage of these critical medical supplies. In many developing countries, reliable power is rare. Access to grid power, especially for rural facilities, simply may not be available. This lack of power, or lack of steady power, jeopardizes the ability of blood banks to safely store blood.

What are the energy requirements of a blood bank?

It is important to understand the continuous electricity demand of refrigeration when designing an energy system for a health-care facility with an internal blood bank or lab. The table below shows the energy requirements of a sample blood bank in Haiti, but it is representative of the loads found in blood banks within typical health-care facilities.

Blood Bank Load Inventory

AreaQuantityLoad (Watts)Operation Time (Hours)Daily Energy (Watt-hours)Total Power (Watts)
Fluorescent Lamps44081,280160
Total Lighting3,5601,260
Total Equipment3,5601,260
Staff Refrigerator1502424050
Blood Bank Refrigerator1667243,200667
Backup Refrigerator1702433670
Total Refrigeration3,776787
Grand Total8,6162,707

Considerations When Choosing a Medical Refrigerator

As the example blood bank load chart illustrates, refrigeration and lab equipment have comparable energy demands. When choosing a refrigerator for blood, vaccine, or reagent cold storage, facility managers should consider numerous specifications that affect the cost of operation and temperature stability. These specifications include capacity, energy use, approved refrigerator use, ambient temperature ratings, power source, holdover time, reliability, price, required training, and refrigerant selection. Care should be taken to ensure that energy-efficient, properly sized refrigerators are used for each facility.

Types of Cold Chain Refrigerators

Different refrigeration technologies have been developed to extend the cold chain to remote areas, including 12 volt electric, liquefied petroleum gas (LPG), and kerosene-powered models. Gas/electric hybrid refrigerators should be considered for facilities with intermittent power supplies.

Temperature-Monitoring Equipment

Temperature monitoring is a crucial part of the cold chain. There are many methods that have been developed to monitor temperature during the transport and storage of medical products.

Additional Resources

  • Step 1

    Analyze Energy Demand and Supply

    Before investing in any energy technologies, a health facility must first understand its current day-to-day energy requirements. An initial energy audit is critical to ensuring proper system design and operation. Learn more

  • Technical Standards

    Cold Chain and Refrigeration Standards

    The World Health Organization (WHO) provides specifications for different categories of refrigerators and freezers used by health-care facilities. It also lists the products that comply with these specifications. View the standards

  • World Health Organization

    The Blood Cold Chain: Guide to Selection and Procurement

    This publication aims to provide basic information on the blood cold chain and guidelines for its management. View the resource

  • World Health Organization

    Performance Quality Safety (PQS) Catalogue

    This resource provides general information on the choice of equipment, together with specific technical and purchasing data for certain items. View the resource