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How CHP improves energy efficiency

When we talk about improving energy efficiency in Serbia, the plant for cogeneration of heat and power (CHP - Combined Heat and Power) is one of the key tools. The main idea behind the CHP system is to use fuel more efficiently. Instead of, as in classic power plants, the heat from the combustion process simply ends up in the atmosphere, CHP systems capture and use it, most often for space heating or process heat in industry. This significantly increases the overall efficiency of primary energy use.

But what exactly does that look like in practice? It is not just about "something" being captured, but about concrete technologies and policies that lead to tangible savings. Let's take a closer look.

The basic principle of operation of the CHP system

At the heart of any CHP system is a simple but effective idea: to produce electricity and heat simultaneously from the same fuel source. This is fundamentally different from the traditional approach, where electricity is produced in large-scale power plants and heat for heating comes from special gas, fuel oil or coal-fired boiler rooms.

Double benefit: electricity and heat

When fuel is burned in a turbine or engine, it drives a generator that produces electricity. However, a significant amount of heat is also released as a byproduct of that process - through exhaust gases and engine cooling. While a conventional power plant would simply release that heat into the environment (thus dropping the efficiency of the entire system to, say, 65-80%), CHP systems are designed to use that heat energy.

Waste heat recovery

That "surplus" heat is then transferred to the network for district heating, in industrial processes that require heat, or even for household needs in the very building where the CHP unit is located. This recuperation or recovery of waste heat is a key factor that enables CHP systems to achieve extremely high overall efficiencies.

In the context of combined heat and power (CHP), an interesting article to read is about easy energy control systems that are available anytime, anywhere. This article explains in detail how modern technologies can improve the efficiency of energy systems. You can find more information in the article at the following link: Easy energy control anytime, anywhere.

How is the efficiency greater than 100% achieved?

This figure may seem like science fiction, but in the context of a CHP system, it has its own logical explanation. It does not mean that more energy is created out of nothing, but that the same amount of basic fuel is used more efficiently.

Calculation of efficiency in CHP

Standard efficiencies for power generation in conventional power plants range from 30-40%, with little heat loss in the process itself. When we add heat for heating (say an additional 30-40%), the total efficiency can reach over 70-80%. However, with modern, high-efficiency CHP systems, especially those using new fuel technologies, that efficiency is raised to an even higher level.

Hydrogen CHP and thermal energy recovery

A particularly interesting example is HEE CHP hydrogen systems. They use advanced Alfa Laval plate heat exchangers that are capable of recovering heat energy in two key ways:

• Chimney cooling: Part of the heat from the hot flue gases, which would otherwise be lost, is captured. This can be a significant percentage, somewhere between 30-40% of the total thermal energy produced in the process.
• Exhaust heat: An additional 15% of heat energy can be recovered from the exhaust gases themselves.

When all this is added up, the efficiency of such systems can exceed 105% compared to the efficiency of fossil CHP systems (which is usually at the level of 65-80%). It is important to note that this "over 100%" does not refer to energy production, but to a more efficient use of primary energy compared to its application only for electricity production. For example, a fuel that would provide 40% of electricity in a conventional power plant can provide the same amount of electricity in a CHP system, plus a significant amount of useful heat, which makes the total utilization of that fuel much higher.

Incentives and regulations for the improvement of CHP in Serbia

Serbia, like many other countries, recognizes the potential of CHP technologies for achieving energy goals and reducing emissions. That is why we are working on creating a favorable environment for their application through incentive mechanisms and legal frameworks.

Action plan for energy efficiency

The Fourth Action Plan for Energy Efficiency in Serbia is one of the key documents that promotes such technologies. It explicitly states an interest in encouraging high-efficiency CHP systems, especially in industrial sectors. The goal is to motivate the industry through such incentives to switch to more efficient solutions for the production of heat and electricity, which directly contributes to overall energy savings at the national level.

Incentive tariffs for high efficiency CHP

One of the specific forms of support are incentive tariffs. This means that electricity produced in highly efficient CHP plants will be purchased at more favorable prices, or additional incentives will be given for its sale to the grid. This makes the investment in CHP more profitable and reduces the payback period, thus encouraging new investments.

New minimum efficiency requirements

Legislation is also keeping pace with these trends. Minimum energy efficiency requirements are being planned or already being introduced for both new CHP plants and those being renovated. This ensures that new CHP investments will comply with the highest efficiency standards, and avoid installing technologies that do not provide maximum benefits in terms of energy savings and emissions reductions. Clearly defined efficiency thresholds become a measure of the quality and reliability of new CHP systems.

Integration of renewable sources and DHC/CHP

Contemporary trends in energy are moving towards a more comprehensive approach that involves the integration of various technologies and energy sources. CHP systems, although often based on fossil fuels, can be a significant part of that integration, especially when it comes to district heating (DHC) systems.

Trends in DHC/CHP

In general, several important trends can be observed in the district heating and cogeneration sector:

• Integration of renewable sources: An increasing number of DHC/CHP systems include renewable energy sources such as biomass, geothermal energy or solar thermal collectors. This reduces dependence on fossil fuels and reduces the carbon footprint.
• Waste heat recovery: In addition to heat from own CHP units, other sources of waste heat are increasingly sought, for example from industrial processes, data centers and even from waste water.
• Smart technologies: The introduction of smart management and monitoring systems enables optimization of DHC/CHP plant operation, heat redistribution and more efficient use of available resources.

Reducing dependence on fossil fuels

By integrating renewable sources and advanced recovery techniques, CHP systems contribute to reducing long-term dependence on fossil fuels. Even when natural gas is used, the high efficiency of the CHP system means that less gas is used compared to producing electricity and heat separately. The transition to green fuels, such as hydrogen, will make this story even more sustainable in the future.

Recently, an increasing number of companies are turning to solutions to reduce peak loads, and one of the most interesting solutions comes from the area of CHP (Combined Heat and Power). This technology enables the simultaneous production of electricity and heat, which can significantly reduce costs and increase efficiency. If you want to know more about energy optimization strategies, you can read this article which explains in detail how peak shaving solutions can contribute to better energy efficiency.

Implementation and potential in Serbia

Although the principles of CHP technology have been known for decades, its wider implementation in Serbia is proceeding gradually. Existing industrial facilities, but also the potential for new systems in cities that have developed district heating networks, offer significant room for progress.

Identification of potential locations

The first step towards improvement is the identification of locations with the greatest potential. These are primarily industrial plants that already consume large amounts of energy for their processes, as well as parts of cities that are already heated by district heating. These locations often also have existing infrastructure that can be upgraded or expanded.

Examples and case studies

Although Serbia has not yet achieved the mass application of CHP, there are individual examples and studies that show its cost-effectiveness and advantages. Analysis of energy consumption in major industrial complexes and comparison with the potential efficiency of CHP systems can provide concrete guidelines for further investments. The focus is on sectors such as the chemical industry, the food industry, but also for the heating needs of residential and commercial buildings.

Challenges and solutions

One of the main challenges for wider implementation is the initial investment, which can be significant. However, with appropriate incentives, favorable loans and a clearly defined regulatory policy, this obstacle can be overcome. It is also necessary to provide professional staff for the design, construction and maintenance of these complex systems. Education and awareness of the benefits of CHP technology among decision makers and industrial users are also key.

The future of CHP technology and energy efficiency

A look into the future of CHP technologies in Serbia reveals the potential for further progress, especially with the development of new fuels and integration with renewable sources. Energy efficiency is not only a matter of savings, but also of energy security and sustainability.

Hydrogen as the fuel of the future

As we have already mentioned, hydrogen CHP systems represent one of the most promising areas. Their ability to almost eliminate CO2 emissions, while maintaining high energy utilization efficiency through heat recovery, makes them ideal for the future of energy. The development of infrastructure for the production, transport and use of hydrogen is a key prerequisite for their wider application.

Smart systems and integrated energy solutions

Future CHP systems will be even smarter, integrated into wider energy networks and better adaptable to changing needs. Smart energy management, with the help of artificial intelligence and IoT technologies, will enable even more precise management of energy production and consumption, optimizing plant operation and making maximum use of available resources.

Contribution to decarbonization

Finally, improving energy efficiency through CHP systems, especially those that use renewable fuels or completely avoid emissions, directly contributes to Serbia's efforts to decarbonize the energy sector. This means cleaner air, less dependence on energy imports and a better quality of life for all citizens. Investing in such technologies is not just an investment in equipment, but an investment in a sustainable future.