WHAT IS ENERGY EFFICIENCY IN COLD STORAGE?
With global increase in Energy Demand, the energy prices have been increasing drastically. This makes energy efficiency gain more significance. Businesses are looking into ways through which energy can be used in a smarter way.
WHY IS IT IMPORTANT TO USE LESS ENERGY?
Less energy usage is good for the economy, environment and overall profitability of a business. Particularly, in cold storage, energy input requirement is quite significant. Therefore, energy efficiency as a way of continuous expanding opportunity to reduce operating costs.
In a typical refrigerated warehouse, 54% of the total electricity consumption is used for for cooling, freezing and refrigeration, 21% used for electric defrost, 10% on Lighting, 9% on office HVAC, 3% for battery chargers and 2% on office equipment.
MEASURES TO IMPROVE ENERGY MANAGEEMENT IN COLD STORAGE
It is important to note that a refrigeration system that works at optimum conditions will always last longer and improves the overall Return on Investment for the company. Therefore, the following will play a major role in ensuring optimal energy usage in cold storage. This can be done through:
1. Replacing Old & Outdated Refrigeration Equipment
The rule of thumb is that as electrical equipment gets old, the efficiency in energy consumption reduces. So, how long do refrigeration systems last? It’s true that they could run for a very long time. However, it is not advisable to run the equipment until it fails. Technology has been evolving so fast and there has been designs of more efficient equipment. For instance, in Kenya, most of hermetic compressors are being phased out using semi hermetic types that are more energy efficient. In most cases, the cost of replacing old refrigeration equipment with more energy efficient types leads to massive energy savings and favorable payback periods.
2. Ensure your evaporator and condenser coils are working properly.
Evaporator and condenser coils should be checked regularly. This ensures that the equipment is free of dust and grease that normally reduce their efficiency. Keeping the coils clean ensures that the unit runs efficiently and consumes less energy. Cleaning also lengthens the useful life of the appliance.
3. Upgrade of the defrost controls
In most cold storage systems, timers are used, hence, defrost is done based on the set time rather than on conditions of pressure and humidity. In modern refrigeration systems, defrosting is done using sensors that detect pressure and humidity.
4. Installation of more energy-efficient light fixtures.
In cold storage, use of certain lights that generate heat such as fluorescent, incandescent and halogen amongst others increases the cooling load. Therefore, replacement with more energy efficient types such as LEDs will save energy since they consume less energy as well as reduce the cooling load.
5. Energy Management Training
In energy management, employees are considered as the greatest resource in managing energy costs. There is need to train employees on best practices in cold storage. For example, employees should be made aware that leaving cold store doors open causes mixing of warm air from outside with cold air from inside the cold store, and this drastically increases the cooling load as the overall energy consumption also increases.
6. Developing a regular maintenance program for the refrigeration unit
The complexity of refrigeration system dictates the need to have a detailed preventive maintenance. Cold room systems require proper maintenance. However, certain operational problems cannot be avoided unless prevented through proper and early maintenance checks. One of the most important aspects of a cold room system for efficient cooling is refrigeration. Including proper maintenance of compressors, fan coil units or FCUs, the condenser and the evaporators, unlike any other equipment the overall cold room refrigeration system should undergo daily, monthly, quarterly and annual preventative maintenance checks. For instance;
On daily basis
- Check each compressor for any oil leakage
- Check all Freon levels for each system
- Check the evaporator for possible ice formation
- Check if PLC switchboard functions properly
- Check secondary system’s head pressure
- Check proper cold room temperature
On Monthly Basis;
- Check the daily maintenance records
- Check system efficiency
- ensure that condenser coil fins are clean
- ensure that the evaporator and unit cooler fins are clean
- ensure reverse blowing is working properly
- ensure proper cooling in full load
- ensure refrigerant levels are well-maintained and working properly
- ensure that control valves are working properly.
- ensure defrosting functions are working properly
- ensure evaporators are working properly
- Clean evaporator casing and blower fans
- Calibrate cold room temperature
- perform a system functional test and check for any malfunctions
On Quarterly Basis;
- perform monthly maintenance checks
- Check overall functionality of cold rooms
On Annual Basis
- perform daily, monthly and quarterly checks accordingly
- perform chemical washing on heat exchanger, as needed
Unisource Energy Kenya is dedicated to helping you identify options for continuous energy
improvement. We can show you how energy is used in a typical cold storage facility and can
help you understand where to focus your efforts.