Energy Efficiency in Food Processing Industry: Cooling and Energy Storage Systems
The food processing industry is a notorious energy consumer. Since food production has to match the human energy balance, the energy supply for this industry is enormous. Natural gas, coal and other fossil fuels are stretched because of such demands.
Consider this fact: Approximately 10J of natural resources is consumed for the production of 1J of food. Human population increase coupled with changing nutritional demands can only make this ratio to increase. Over the past few decades, the food processing industry has enhanced efforts to promote waste heat recovery and improve energy efficiency. New technologies have replaced conventional ones in areas such as chilling, sterilization, freezing and pasteurization.
What are the efficiency levels in your cooling and energy storage systems for food processing, especially in the face of the COVID-19 pandemic?
Global Pandemic Impacting Food Processing
There is no doubt that the food chain has suffered from the COVID-19 pandemic. Layoffs and lockdowns have contributed to a temporary decline in demand. In the longer run, the role of food safety is set to become more apparent. Production system designs will probably need to change to accommodate new safety and hygiene requirements.
With the current momentum, there is a need for more sustainability in the food processing industry. A global event of this nature weakens many systems. The resilience of the food system is not spared.
Already, there is a notable change in diet and consumption patterns. People are buying more storable and fresh foods. Owing to food safety worries, the sale of animal products seems to be declining. With restaurants and other food services prohibited in many areas, online orders are on the increase. Operating methods have also transformed to adhere to COVID-19 containment guidelines.
Energy Efficiency and Food Processing
There are several strategies towards averting challenges in the food processing industry in the wake of COVID 19, ranging from regular wiping of surfaces to enforcing social distancing. Amidst these steps, it is evident that balancing between human safety and product movement is delicate.
The need for energy efficiency in food processing industry has never been higher. Enhanced refrigeration capacity and cleanliness means that budgets can be stretched. This burden can be minimized with energy efficiency steps such as adopting efficient systems and promoting energy efficient culture among the workforce.
Food processing requires reliable and accurate cooling. Applying the best cooling systems is important because this process consumes considerable amount of energy. Energy efficiency measures in cooling systems not only promote profitability, but also minimize greenhouse gas emissions.
Cooling in food processing involves passing the product through a cooler or heat exchanger. A major component of this system is the cooling medium, which reduces temperature. It often recirculates in the system.
With the need to cater for different cooling processes and achieve varying energy savings, several cooling technologies exist. Absorption cooling is a popular replacement for mechanical cooling. Absorption chilling or cooling technology was already available in the 1900s, but the first recorded commercial application was in 1923. This technology is old, so it is understandable that it has undergone huge improvements over the century.
While the compression chiller relies on electricity, the absorption chiller derives its power from external heat sources such as steam and hot water. Absorption chillers are excellent replacements for compression chillers if power is unreliable, costly or unavailable. This technology uses an absorbent and refrigerant combination to transfer heat.
Fig1: Processing Industry Plant with Heat Recovery System and Integrated Energy Storages Tanks
Absorption chillers are also ideal for heat recovery in the food processing industry. Using this system with a cogeneration plant minimizes energy waste in food industry. The hot water emanating from the cogeneration plant drives the absorption chiller.
Energy Storage Systems
Industrial processes typically produce large amounts of thermal energy that may exceed definite need. For an industry experiencing low demand, there is need for reduced energy bills. This calls for less emissions and reduced peak demand. The challenge is that excess thermal energy is lost because it usually does not coincide with peak demand.
Instead of wasting the cold or hot thermal energy, facilities can find a reliable method to capture and store the energy. Hot thermal energy could be stored for cleaning out animal fats, sanitizing surfaces and other cleanliness applications. This system can be instrumental in adhering to COVID-19 cleanliness measures and promoting energy efficiency in food processing industry.
There is another COVID-19 requirement for food to be cooled rapidly for later use. This means that commercial establishments might need additional cooling capacity, which can be delivered by a thermal energy storage tank to coincide with demand.
The TES tank imitates a battery, charging with thermal energy and releasing the same during peak demand. If food processing is intermittent, the TES system can reduce peak demand significantly. Peak power demand also reduces because of the enhanced load shifting.
Most TES tanks operate on a 24-hour storage cycle. The system may accept electrical or thermal input, but the output is thermal. Energy storage systems for food processing industry enable the facility to take advantage of cheap electricity rates. By spending more energy from the grid in off-peak periods, the system may attract incentives from the utility company.
Other advantages of the TES system are:
- Environmentally friendly
- Room for future expansion
- Suitable for large load for a short term
- Standby capacity for repairs or emergencies
Given the challenges that most sectors of the economy are facing especially during COVID-19 period, it is encouraging to note the various energy efficiency measures in the food processing industry can apply. ARANER will support these efforts through relevant experience and knowledge.