Energy efficiency improvement, modernization

In the case of existing and operating refrigeration equipment and systems:

The cooling system is an integral and vital part of many facilities, such as certain factories, retail stores, skating rinks, cooled warehouses, etc., and the refrigeration system itself is often also the most significant consumer of electric power in these cases.

Owing to this, the cost of electrical energy used by the refrigeration system is directly and prominently reflected in the price of the products or services provided, so it is only logical that all operators and investors, whether in case of a new investment or an existing refrigeration system, should aim to operate these systems in the most optimal and energy-efficient way possible.

We have seen many cases during our career, where the refrigeration system consumed unnecessary amounts of electrical energy either because of a malfunction, or simply because it was set to inappropriate operating parameters. Exploring and fixing such problems can lead to a significant and immediate reduction in consumption.

Of course there are other instances, where even with proper operation and settings of an existing system, the use of electrical energy is still high, but this doesn't mean that it should remain so.

It is true for almost all refrigeration systems that it is possible to significantly reduce the electricity consumption (even by 10%...40%) - with smaller or larger improvements to the system – with good ’return of investment’ values. Furthermore, in those cases we can often notice an improvement.in cooling capacities or temperature levels as well.

It is important to note that this approach is not the same as what is now practiced by some companies specialized in only one product type/solution and trying to apply this same solution to any type of system.

As every refrigeration system is different and every component and aspect of a cooling system is dependent on each other, there is no clear recipe for what interventions are possible and practical for the given system. The possibilities must be examined and analyzed individually in each case, to achieve the greatest improvement with a given budget, or to realize the necessary improvement with the lowest cost..

These kind of improvement potential is there for almost all types of refrigeration systems in general, i.e. it also applies to conventional freon, carbon dioxide, ammonia and other refrigeration equipment. In many cases the best result – economically – is achieved by implementing several smaller interventions rather than a single radical change.

The usual steps for performing such tasks are:

• Contacting the operator, gathering knowledge of operational experiences, known errors or any condition that contributes to the dissatisfaction with the system
• Exploring the operating details of the cooling system on the basis of wiring plans, schemes and information obtained during on-site visits
• Recording of operating parameters, examination of actual operating data and parameters by performing various measurements as necessary
• Determining if the system or the installed individual components (compressors/heat exchangers etc.) are adequate for the required capacities/temperature levels (based on the information received and obtained earlier), or if there is any possibility of a malfunction in the system. Investigation of any such malfunctions and the losses they inflict at the system level
• Analysis of reasonable and economically justifiable (realistic return of investment) development possibilities, specification of investment and achievable savings with return of investment calculations
• Carrying out the complete conversion, modernization and improvement of the system on demand

The nature of these tasks are somewhat similar to the work of a detective: we must find the causes going back from the results, which can be a serious challenge for an extensive and complex system.

The list of possible and common interventions include (but is not limited to):

• Fine tuning of control parameters, improvement of control system if necessary and possible
• Implementing adaptive evaporation and condensation pressure control
• Modification of system logic (for example multi-stage switching)
• Implementing active level controls
• Installation of continuous inert discharge
• Implementation of PLC control on older types of industrial screw compressors with automatic capacity control, and, if possible, automatic volume ratio control
• Modification, expansion or replacement of heat exchangers
• Replacing electrical defrost with hot gas defrost or other solutions using recovered waste heat
• Changing condenser for adiabatic, evaporative or hybrid type condenser.
• Change-over to indirect, gravity fed chillers, or introduction of “falling film” heat exchange technology, mainly in the dairy industry or other systems with ice water thermal storage (technologies requiring + 1 °C ...+ 2 °C of water)
• More modern equipment (fans, pumps etc.) and electric drives (motors) with reduced power consumption.
• Refit with modern refrigerant

Life Cycle Cost-based approach for new investments:

Naturally, the issue of energetics is of high priority not only in the case of an existing and operating cooling system, but also in the case of a new one to be built.

It is true for almost every productive projects that the investment price cannot be interpreted in itself. An accurate and complete picture is only available and a responsible decision can only be made if the investor considers the investment price and operating costs together, and makes the decision based on the lifetime total cost, and in our opinion, this is the sole way to do it.

Lifetime cost assessment means that the base amount whereon the decision is based is not simply the investment amount, but a total cost for a given period (for example 5-10-15 years, according to the investor's ideas), The total cost is of course based on the investment itself, but it also includes operating and maintenance costs, electric power and possibly water consumptions, etc.

It is not rare that the differences between the one-time investment costs of each technical solutions will be returned within 1-2 years, so choosing a certain solution can also be interpreted as an exceptionally good investment from an economic standpoint.

In our practice, we also perform such calculations and comparisons in the conceptual design phase, therefore our customers can choose and customize the best technical solutions for themselves, doing so by anticipating and taking into account their medium and long-term total costs.

The refrigeraton system as an integrated energy center:

Significant amount of waste heat is produced in the cooling system, which is normally simply discharged into the environment through the condenser. The actual amount of this heat and temperature levels depend on many factors, but in general 120% to 180% of the installed cooling capacity in order of magnitude,  for example a cooling system with a rated cooling capacity of 300 kW, 360 kW… 540 kW heat is generated, which is very significant.

It is obvious that if the operator has paid for the electricity needed to operate the cooling system anyway, then not only the cold but also the warm energy (as a by-product) should be utilised to the fullest extent possible. If the operator only use the cold side, then for example in the case of a system operating with a COP (Coefficient of Performance) equal to 1.5, 1.5 units of cold energy can be realized from 1 unit of electricity, while if the hot side can also be utilized, then it will already extract 2.5 units of heat energy in total from 1 unit of electricity, and thus can partially or completely replace the previous (for example  gas-based) heating solutions.

Although the above seems favorable at first, several other aspects need to be examined, like:

• The bulk of the recoverable waste heat is at a lower temperature level, it is only enough to produce ~ + 30C… + 35C water, while a smaller, 10..20% part of the total quantity of heat is adequate to produce + 50C… + 80C water. Accordingly for the use of heat available at a lower temperature within the facility, the building services system shall also be designed to be able to utilize the water at a lower temperature.
• The refrigeration system is not a boiler, so hot energy is not certainly available when needed, but when there is a cooling demand. Just think about it, in summer generally higher cooling loads occur, and there is a lot of “waste” heat generated, but it is not the period when heating is needed.

It can be stated regardless of the above, that in almost every facility that requires cooling, the refrigeration system itself can perform all cooling (including comfort cooling), and heating tasks, whether it is a comfort heating, utility or technological hot water production or other heating task. Its design cannot be examined only from the viewpoint of the cooling system, but must be treated together with building engineering, building electricity, technology, etc.

Energy center based approach of the refrigeration system and the facilities realized along this approach are the most modern today in aspect of energetics for the building as a whole.

According to the needs of our customers, we undertake the energy review of all new and existing cooling systems, the preparation of modernization and energy efficiency enhancement plans.

Our most important specializations:

• Vegetable and fruit processing plants
• Meat processing plants, slaughterhouses
• Intermittent and continuous freezers (freezer box, plate, spiral, fluid bed freezer, etc.)
• Refrigerated logistics centers, cooled and freezer warehouses
• Commercial refrigeration (large stores, retail stores)
• Refrigeration technology in dairies
• Refrigeration technology for beer, wine, soft drink production
• Skating rink technology
• Extremely energy efficient industrial liquid chillers and heat pumps
• District cooling and heat pump technology (up to 10-20-30 MW equipment/systems)
• Pharmaceutical refrigeration systems (for example: blood plasma cooling, freezing)
• Oil and chemical industry cooling systems (also ATEX on request)
• Unique and special cooling and freezing tasks (for example: test and laboratory cooling, solar cell cooling)
• Extra low temperature cryogenic systems

We hope to find you among our satisfied customers soon. To learn more about us, please read on among our other services and products. If you are interested or have a specific request, please feel free to contact us at one of our contact details.