Refrigeration is considered as the key reason behind higher energy costs of any organization. There are different ways by which one could reduce the energy costs – starting from installation of refrigeration system to maintenance. Cold rooms help to store huge quantity of food for prolonged time, and need to be maintained at a specific temperature.
By adopting simple steps to improve the energy efficiency of refrigeration, one could realize significant cost savings. Let us learn more about smart steps that help to save on energy costs. The section is divided into three – maintenance, operational and installation to easily understand about the topic.
Let’s get started…
1. Regular Maintenance
Maintenance plays a key role in retaining the energy efficiency of cold rooms. Most of them call the service provider when the system breaks down, which could affect the integrity of your business. Regular maintenance helps to identify issues before they prove to be detrimental. Maintenance of cold rooms should be done by skilled workers and should take into account different aspects like cracks, loose sealing etc.
2. Ensure sufficient Refrigerant
Refrigerant or coolant is the gas that helps to transfer heat energy in the cooling system. If level of refrigerant is low, it can result in reduced cooling and thereby reduced efficiency. Cooling system has to be recharged with refrigerant so that it could work properly.
3. Fix Refrigerant Leaking quickly
Refrigerant leaking if any has to be fixed quickly to ensure that the cold room works efficiently. Some of the main causes of refrigerant leaking are broken pumps, improper cold room installation, reduced refrigerant levels, air leakage etc. A skilled HVAC employee would be able to fix the refrigerant leakage easily. Refrigerant leaking can result in safety and financial risks for the business owners and not should be fixed immediately. Detectors can be mounted near the plant specifically at points where there is probability of high-leakage.
4. Wash Evaporator Coil quarterly
Unclean evaporator coil is considered yet another reason for inefficient cold room system. It prevents proper airflow in the system. Evaporator coils has to be cleaned regularly, at least quarterly to improve the cooling efficiency. Different factors need to be considered before setting cleaning frequency like, the location of cold rooms, age of cold rooms etc.
5. Replace old inefficient compressor
Compressor is the main part of a cooling system and works on the basis of electricity and capacitor and results in the flow of refrigerator. If you could see symptoms like reduced cooling ability, inability of the compressor to start and compressor overheats, replace old inefficient compressor with a new one after seeking professional expert.
6. Engage with fast respond maintenance team, able to get the problem fix immediately
Always seek help from professional HVAC experts who are able to identify the problems and start working on the issues immediately. If the team does not respond to your queries quickly, go for other technicians who are available around the clock.
7. Make sure the Door Seal condition is good
Door seal condition needs to be checked on a regular basis and ensure that it is flawless. If there is any vents in door seal, it would not be able to serve the purpose effectively.
8. Clean condenser regularly
Condenser also need to be cleaned regularly to improve the lifespan of cold rooms and to improve its efficiency. Soft brush can be used to clean the condenser. Make sure to work carefully without damaging the unit.
9. Monitoring energy usage
It is imperative to monitor energy usage by using a reliable energy meter. If you are able to identify any unexplained spikes in energy consumption, reach out to a reliable service provider. Keeping track of energy consumption inspires people to keep a control on the energy consumption and to set future goals.
10. Don’t sprinkle water on coils
Never sprinkle water on an air-cooled coil as they are not designed to have any interaction with water spray. Water can result in corrosion or other microbial problems.
11. Learn about low-cost technologies
Discuss with the technicians about the possibilities of any low-cost system that could replace the existing system. If there is any issues like increased noise or any unusual behavior from the system, update the information to the experts.
12. Check room for energy wastage symptoms
Rooms need to be checked regularly to identify if there is any energy wastage that could be reduced or controlled. Switch off the lights inside the room and verify if external light can seep into the room. Door misalignment, vents, damage etc. can also be checked by this.
13. Calibration of gauges
Operators need to verify that thermostat or thermometer is accurate by performing regular calibration of gauges with respect to tested and approved instruments. Ensure that the timer settings in automatic electric defrost is proper ( if the defrost is turned on for longer time than required, it could result in increased energy expenses).
14. Install thermal imaging camera
A thermal imaging camera can be installed inside the room to verify if there is any hot-spots inside the room.
15. Upgrade the system technology
Investing in a good technology would help you earn benefits in the long run. Some of them are as follows : automatic fault detection system, high-efficiency motors, electronic expansion valves etc. Other technologies in which you could invest are variable speed drives in compressor, efficient pipe insulation etc.
16. Upgrade the room
There is a galore of options available to upgrade the cold storage room like cabinet doors and lids, strip curtains, high-speed closers etc. Reflective coating can be used on external walls and roofs to reduce heat build up.
So read on …
1. Open the door less frequently
Hot air that is trapped inside the cold room is one of the main causes of reduced efficiency of cold room. Statistics reveal that this amounts to almost 30% of heat energy absorbed by cold room. By opening the doors of cold room less frequently, one could save energy to some extent.
2. Always close the doors after entering and leaving
Make sure to close the door after entering and leaving. Double-checking the cold room (if the door is closed properly) is a good practice and should be followed by all employees, every time for maintaining the temperature low. This helps to reduce the seepage of hot air into cold room.
3. Load or unloading the goods in batch so we can minimize the frequency of opening the door
Loading or unloading single stuff at a time from the cold room would increase the frequency of opening the door. This could also increase the heat build up inside cold rooms. Operators should take special care to load and unload goods in batch as it helps to decrease the frequency of opening or closing.
4. Shut down refrigerator when lots of goods need to be loaded and unloaded
If there are too much of goods to load and unload, you may shut down the refrigerator until the loading process is completed. This helps to reduce energy expenses significantly.
5. Less human employees in cold room
Make sure that there are less human employees in the cold room at any time. Average human body temperature is 37 degree Celsius, which could also increase the heat flow to cold room. By maintaining less employees, average temperature would be lower which implies cooler cold rooms.
6. Loading and unloading of goods in early morning or during evening
Another proven technique to improve the energy efficiency of cold rooms is to do the loading and unloading of goods in early morning or during evening. If goods are loaded or unloaded during afternoon, it could result in unwanted heat gain in cold rooms.
7. Adopt good loading unloading policy
Employees need to follow a loading and unloading policy to improve the cooling efficiency. Scatter goods that need to be cooled to promote optimum air circulation around the packages. These goods can be later consolidated together for freezing. High-turnover products can be kept near the doors of cold room to allow effortless access.
8. Switch off the cold rooms during night if needed
Wonder why our parents ask not to use high-energy consuming equipment like iron-box during night? It is because energy consumption is higher during night. Same concept is applicable to cold rooms as well. If the temperature is not critical for your product, you may switch off the cold rooms during night.
9. Only put necessary things in
Make sure that there are only necessary goods inside the cold room. If you keep on adding goods that does not require cooling, it would necessitate the refrigerant to pump harder, which results in less efficient cooling process. Keep close track of cold room and remove unwanted goods to improve the efficiency.
10. Ensure goods has not warmed up
Ensure that the goods that you wish to load into the cold room has not warmed up as a result of remaining outside at a hotter temperature. All the goods that you wish to load into cold room has to be cooled a bit, this helps to reduce the extra effort that has to be attributed by refrigerant to make an extra effort to cool the goods.
11. Use LED lights
LED lights are efficient compared to other lighting options like CFL, incandescent lights etc. This is because LED converts 80% of input power to light energy and the remaining 20% is only converted to heat energy. Whereas, for CFL lamps, only 40 % of input power is converted to light energy. Cold rooms can be equipped with LED lights as they are energy efficient.
12. Switch of the light when room is unoccupied
Operators can turn off the light if the room is unoccupied (even if you use LED light) to save on energy bills. Lights can result in the build up of heat energy inside the system. Door-limit switch or occupancy sensors can be installed to automate this process.
13. Train your staff to be efficient on loading or unloading goods
Staff should be aware of the steps that they could adopt to improve the cooling efficiency of cold rooms. They should be encouraged to do loading and unloading as quick as possible to prevent heat energy from getting trapped inside the cold room.
14. Never overload cold room
A fully loaded cold room would result in lesser cooling. It is better to maintain cold room up to 60% full and freezers up to 75% full for optimum cooling. Never overload the cold room with goods, as this tends to decrease the cooling efficiency.
15. Set evaporator temperature as high
Evaporator temperature should be set to the highest level to get more efficiency from the refrigeration process.
16. Ensure the Curtain is properly closed every time entering or leaving the cold room
Ensure the Curtain is properly closed every time before entering or leaving the cold room. This helps to seal the cold room properly and prevents the flow of hot air into the room. Make sure to close the door tightly to prevent flow of hot air. A flashing indicator or an alarm can be used to warn the employees of opened doors even if the door is opened for shorter time.
17. Separate different temperature zone if 2 different temperature range required
If there is different temperature requirements for different goods, make sure to separate the different temperature zones. This helps to give the required cooling to goods (without excessively cooling the goods).
18. Use better heat recovery technologies
Refrigerant desuperheater waste-heat-recovery system helps to reprocess unwanted heat energy from the cooling system system. It can be then used to warm up water or other liquids. It also helps to reduce the temperature and pressure of refrigerant, by decreasing input energy. They are the best fit for applications that demand regular heating requirement. Desuperheaters can used with different types of aircon compressors like scroll, rotary, reciprocating, screw-type etc.
1. Use quality materials for insulation
Ensure that you have used supreme quality insulation material for the cold room. Insulated envelope should be flawless for energy-efficient cold room. A room that is sealed off by insulated walls from all sides is coined as insulated envelope. High quality insulated envelope helps to reduce the energy consumption of cold room.
2. Engage reputable installer
Make sure that you depend on only well qualified and experienced HVAC installers to perform the cold room installation. As the proverb says, well begun is half done. A reputable installer would be able to find the best location for performing installation.
3. Insulation features in walls, floors and ceilings.
Another method by which one could improve energy efficiency of cold rooms is by using insulation features in walls, floors and ceilings. Perfectly sealed or insulated rooms ensure that there is no inflow of heat energy into the room. This helps to save on your energy bills considerably.
4. Right size of cold room
Size of the cold rooms also have a say on the energy consumption. Make sure that you are clear about the cooling requirements, before deciding the size of cold room. Cold rooms should not be too big, as it might result in loss of energy. Optimally designed cold rooms help to save on energy bills and thereby reduces energy consumption.
5. Seal the gaps
Gaps found between the insulated panels or pipes is one of the main culprits of very high-energy bills. Hot air could easily find its way into the cold rooms through these energy gaps, which demands high energy for efficient working. Make sure to seal the gaps to prevent the flow of warm air.
6. Set operation temperature according to the recommended temperature range
Operation temperature or working temperature should be set as per the recommended temperature range. It should neither by too low nor be too high as it could result in higher energy bills. Operation temperature should take into account factors like size of cold rooms, cooling requirements etc.
7. Use automatic doors
Automatic doors is yet another method which could help to maintain energy efficient cold rooms. Keeping doors closed is one of the basic steps that one need to adopt to improve the energy efficiency of cold rooms. However, if an employee forget to close the door, it could result in serious losses. By introducing automatic doors, we could automate the whole process and feel bit relaxed.
8. Remove all obstacles
Air flowing from evaporator should be allowed to flow freely without any obstacle or hindrance in between. Cold temperature could be retained by allowing flawless airflow. This helps to maintain optimum temperature in the cold room, which is imperative for an energy efficient cold room. Don’t cover the system as it could block proper airflow to them. Remove all the obstructions like decorative covers, vegetation etc. to allow free airflow through the system. If the fins are bent, straighten them.
9. The evaporator blowing direction should not face the door
Hot air flowing from the evaporator should not be directed towards the door of cold room. This could increase the temperature and results in reduced operating performance.
10. Install occupancy sensors
Low-temperature occupancy sensors can be installed in walk-in refrigerators. This helps to save on lighting expenses and decrease the compressor load.
11. Walk-in refrigerator controller
Another innovative method by which business owners could reduce the energy costs is by using walk-in refrigerator controller. This works be reducing the speed of refrigerator fan when it does not need full speed.
12. Consider scroll compressors
Studies prove that scroll compressors are better compared to reciprocating compressors as they help to decrease the consumption of electricity significantly (up to 20%).
13. Away from heat source
Cold room needs to be located in a place away from any heat sources ( including direct sunlight). There should be proper space around the vents in cold room to allow free flow of air.
14. Use efficient refrigerants
There are a slew of refrigerant options like synthetic, natural refrigerants etc. Identifying the right type of refrigerant helps to increase the energy-efficiency of the system. Refrigerants like R134a consumes less power compared to other alternatives. If you are interested in natural refrigerants, go for options like ammonia, hydrocarbons etc.
15. Ensure enough capacity design
If the system is not designed properly, you would end up paying more in terms of the operating expenses. It could also result in reduced life span of the equipment. Reducing the size of evaporator / condenser and increasing the size of compressor is a bad practice. Oversized rooms can result in higher initial capital cost. Energy costs would also be higher for oversized rooms.
16. Install inverter in cold rooms.
This helps to combat unexpected power outage and to maintain the goods cool. Cutting-edge inverter technology using integrated variable speed technology can be implemented in storage rooms that demand varied load settings. (Varied load requirements situations like more power is needed during weekdays and less during weekends etc.)This helps to bring down power consumption and to cater to the specific load requirements only.
17. Install suitable PU installation thickness
Make sure to install suitable PU installation thickness to suit different temperature ranges. Insulation thickness for different temperatures are as below:
- 50 mm for 5 degree Celsius
- 75 mm for – 10 degree Celsius
- 100 mm for – 25 degree Celsius
- 125 mm for – 35 degree Celsius
- 150 mm for – 45 degree Celsius
Finally, by implementing above cold room energy saving tips, you can achieve great saving immediately.