“No energy transition without energy efficiency” is the title of dena’s “Topics and projects” section on its homepage1 “The best kilowatt hour is the one saved,” says Thomas Kübler, Managing Partner of KÜBLER GmbH. Both mean the same thing: It’s about curbing energy consumption in general and especially in companies. Because this is an enormous lever for achieving climate targets. And that’s not all: energy efficiency also pays off economically if it is approached in the right technological way. Modern infrared heating technology plays an important role here, especially when it is intelligently combined with condensing boiler technology.

Condensing technology converts waste heat into usable energy

The special feature of condensing technology is that it extracts the condensation heat (known as calorific value) from the waste heat of heating systems, makes this energy content usable and thus significantly increases the overall efficiency of the systems. Depending on the fuel, this is referred to as oil or gas condensing boiler technology. In short, condensing boiler technology is characterized by the fact that it increases the degree of energy utilization and thus energy efficiency.

How waste heat recovery with condensing boiler technology works

The functional principle of condensing boiler technology is basically very simple. Using infrared heating as an example, the energy contained in the exhaust gas is cooled down to the point of condensation and the heat obtained in this way is transferred to a storage medium (usually water). The heated water is fed to a buffer tank and from there, depending on demand, fed into a standard pumped hot water heating network. Water is the ideal storage medium, but other media such as air can also be used and harnessed in hot air blowers, for example.

Start by identifying and reducing your waste heat sources

It is not only heating systems that generate waste heat; depending on the operating mode, waste heat is generated in a wide variety of places. Ovens, machines (especially air compressors), cooling systems and/or uninsulated pipes are probably the classics. Get to the bottom of the causes of unused waste heat by thoroughly analyzing and evaluating energy consumption throughout the company. The next step is to avoid or at least reduce unnecessary waste heat by optimizing processes. The following questions will help you do this:

  • Can you avoid idle times?
  • Are all systems/processes really running efficiently, or can a few adjustments be made here and there?
  • Are some processes perhaps oversized?
  • Are there heating or cooling phases that would not be necessary in practice?
  • Do you maintain your machines and systems regularly?
  • Do you insulate sufficiently?

With a comprehensive analysis, you can already save a lot of waste heat. And the rest? It’s best to use it sensibly, depending on your requirements.

Put the energy gained from condensing boiler technology to good use

The practical thing about condensing boiler technology is that you can use the waste heat in a variety of ways to increase energy efficiency in your company. “Hybrid heating” is an important keyword here. This is because waste heat can play a major role in hot water preparation or heating rooms. While this variant of waste heat utilization has already established itself in many private households, it is still far from being used everywhere for heating hall buildings. Yet this building segment in particular has a reputation for consuming a lot of energy due to the dimensions of its rooms. There is great potential for savings here. In the industrial sector, for example, the recovered energy can be used for domestic hot water or for hot water-based (hybrid) heating. This often makes sense for offices or social rooms, which are typically connected to halls. In the sports sector, hot water is often used in sanitary facilities, especially for shower rooms. Where appropriate, hot air can be used via hot air blowers to supplement energy-efficient infrared heating.

Bundle your energy flows for greater energy efficiency

Not only the waste heat from heating systems can be harnessed, but numerous other heat flows in the hall building also offer interesting, efficiency-enhancing potential. Namely when you intelligently combine condensing boiler technology and heating. One example is the H.Y.B.R.I.D. infrared heating system from the Ludwigshafen-based hall heating specialist KÜBLER. The fully integrated solution offers great flexibility in the integration of different technologies and energy sources. For example, the hybrid system can utilize the energy flows from the process (machines, compressors, etc.) at the same time as the waste heat from the heating system. At a textile machine manufacturer from North Rhine-Westphalia, the energy flows from the heating system, curing ovens and compressors were combined in this way. Since then, the heat requirement of 1,200 m² of office space can be completely covered by the use of residual heat.

There are also numerous other possible combinations. What is particularly interesting in view of the usually large roof areas of industrial halls is that the hybrid system, which has won several awards (including “Germany’s most sustainable product”, German Sustainability Award 2012), can also integrate renewable energies such as solar thermal energy (keyword: Helio.B.R.I.D.). Heat pumps can also be integrated. In addition, the hybrid system is the basis for the implementation of digital hall heating (e.g. WÄRME 4.0), which makes it possible, among other things, to continuously run the system on an ideal line through real-time monitoring of current consumption. The combination of condensing boiler technology and energy-saving heating technology therefore allows you to ensure greater energy efficiency in your company in a variety of ways.

Why you should focus on your company and climate targets at the same time

Only around half of German companies are aware of their waste heat potential – as dena writes in its publication on waste heat utilization as part of the Energy Efficiency Initiative2. This means that an estimated 226 TWh of usable heat goes unused every year. That is 36% of the energy used by the entire manufacturing industry. Clearly, this costs companies an enormous amount of money, but at the same time the unused waste heat has a negative impact on the environment. Around 60 million tons of the greenhouse gas Carbon dioxide evaporate unnecessarily into the atmosphere every year. In view of rising energy costs and climate protection targets, companies simply can no longer afford to do this.

Make environmental protection your economic efficiency measure

The fact that waste heat recovery with condensing boiler technology is achieved with virtually no additional consumption costs should be of great interest to many hall operators. Overall, the integrated KÜBLER residual heat recovery in the hybrid system allows up to 15 percent of heat to be recovered and utilized. Thomas Kübler, founder and managing partner of KÜBLER GmbH Energiesparende Hallenheizungen: “This figure, in addition to our already extremely energy-efficient infrared systems, marks a quantum leap in economical and environmentally friendly hall heating. Energy savings of up to 70 percent* can be realized in the overall system.”

* Compared to conventional technologies

How the combination of condensing boiler technology and IR heating pays off in practice

Practical examples show how these values pay off for hall operators. Carbon dioxide emissions were reduced by around 65% by modernizing the heating system with the KÜBLER H.Y.B.R.I.D. system in a production hall of the AZO Group in Osterburken. Specifically, from approx. 226,400 kg p.a. to approx. 79,800 kg per year. Greater energy efficiency was also the focus at Reiners + Fürst. The energy savings achieved by the textile machinery manufacturer during the energy-efficient refurbishment of its production and storage areas were also around 65%. The savings here amount to around 46,5000 euros and 299 tons of Carbon dioxide emissions per year. Incidentally, Reiners + Fürst was awarded first place in the Energy Masters Award in the buildings category in 2014 for the refurbishment of the hall heating system and the integration of residual heat utilization in the hall heating, compressed air and curing oven in the H.Y.B.R.I.D. system.

The bottom line: hybrid heating with condensing boiler technology pays off – especially financially!

Using less energy to generate heat saves money. That is crystal clear. How this translates into concrete figures depends on various factors, such as

  • The type and size of your company
  • The volume to be heated
  • The number of processes that generate waste heat
  • The heating system you use

Conclusion: Optimization potential can be found in many different places

Hall modernization, proper insulation, highly efficient heating systems, condensing boiler technology and other options for modern waste heat recovery: there are many ways to increase the energy efficiency of your business and reduce costs. Feel free to contact us and let us discuss how you can use the waste heat from your heating and production processes sensibly instead of disposing of it unused through the chimney.

1 Weblink: https://www.dena.de/themen-projekte/energieeffizienz/

2 Cf. 1445_Broschuere_Abwaermenutzung.pdf (dena.de)