Challenges for Power Plant Chemistry due to the “Energie- und Wärmewende”
Heiko Woizick
The ever increasing speed of the energy and heat turnover has a great impact on power plant chemistry. While the decommissioning of more and more coal- and lignite-fired power plants is reducing the analyses of fuels, ashes and the classic power plant by-products, new technologies are also creating new challenges for power plant chemistry.
Gas-fired and combined-cycle power plants, which will still be needed in the long term, are being used more and more flexibly. The monitoring, conditioning and preservation of the water-steam cycles of combined cycle power plants must therefore be adapted. How can steam purity be achieved more quickly at plant start-up and measured reliably? Does the conditioning of the water-steam cycle have to take into account the increased material stress caused by the higher load gradients? How do you maintain the plants when you do not know exactly how long they will be out of service, but you have to be ready to start them up at short notice?
Increasing the operational reliability of demineralisation systems using correlation diagrams – The new language of demineralisation lines
Dieter Mauer
The DI line speaks its own language, and this can be understood very well using correlation diagrams. These are X/Y representations of pH and conductivity in one diagram. The paper clarifies the question of what the Na+OH-–line in the diagram is, what the H+HCO3–-line is and why there are forbidden areas in the diagram. It also describes how the increasingly important pH measurements can be carried out with virtually no maintenance. We get to know examples of how DI lines express themselves ‘eloquently’ and what sometimes very surprising conclusions can be drawn from this. However, the usefulness of this new language goes beyond the mere interpretation of system behaviour. For example, it is possible to auto-calibrate pH measurements using SW – to an accuracy of a few hundredths of a pH! No calibration using a buffer solution can achieve this, especially not over many months or even longer.
When the pumped liquid is challenging: hermetically sealed centrifugal pumps
Jens-Christian Poppe
Cooling water treatment and biocide use
Holger Ohme
The chemical treatment of cooling water aims to prevent deposits and to ensure corrosion protection, with an increasing focus on controlling microbiological activity. Modern water treatment techniques rely on demand-based dosing of chemicals and biocides through monitoring and automation. Critical deposits, especially biofilms, are caused by microbiological growth and contribute to over 30 % of corrosion damage. The use of phosphonates as hardness stabilizers requires formulations that are stable to oxidizing agents, while the demand for biodegradable dispersants is increasing. In addition, fouling by mussels, especially the quagga mussel, poses a challenge for cooling systems. When selecting oxidizing biocides, consumption factors must be taken into account, since various substances can influence the effectiveness. Monochloramine offers an economical alternative to other biocides because it acts selectively and shows fewer side reactions. Advances in technology enable precise control of biocides and inhibitors through maintenance-free sensors and imaging techniques.
The ‘H2-Wyhlen’ living lab – challenges and opportunities in the construction and operation of power-to-gas plants using the example of a demonstration project
Reihaneh Zohourian, Hepke Kruse, Vassilios Vrangos and Prof. Wolfram Münch
Prosperity and Growth – What do we need to change?
Franz Josef Radermacher
The world is in great difficulty. The growing conflict between the USA and China is tearing apart the existing rules-based order. We are now seeing a new ‘division’ in the world of nations. On the one hand, in reaction to the Ukraine conflict, and on the other hand, worldwide in relation to cultural issues, e.g. family values, language use or political governance. We are living in a cultural crisis and experiencing cultural conflicts worldwide. There is no real progress on the issues of energy and climate, which are particularly important for the future. In this area, which absolutely requires a global perspective and appropriate action, we are focusing strictly on national, or at best European, approaches.
The role of biomass in the production of iron, steel and cement
Jenny Jones, Leilani Darvell and Bijal Gudka
DNV: Germany set to secure energy independence, but narrowly miss climate target
DNV
Data: IEA – Electricity 2025
International Energy Agency (IEA)
Strong growth in electricity demand is raising the curtain on a new Age of Electricity, with consumption set to soar through 2027. Electrification of buildings, transportation and industry combined with a growing demand for air conditioners and data centres is ushering a shift toward a global economy with electricity at its foundations. The International Energy Agency’s Electricity 2025 provides a deep and comprehensive analysis of all these trends as well as recent policy developments. For the period 2025 through 2027, it forecasts electricity demand, supply and carbon dioxide (CO2) emissions for select countries, by region and worldwide. The report explores emerging trends such as growing electrification, expanding power systems and an increasing share of weather-dependent energy sources in the generation mix.
Gas prices expected to experience moderate fluctuations amid balanced market conditions in 2025-2026
GEFC Gas Exporting Countries Forum
The level of gas prices is a key factor impacting gas demand and the competitiveness of natural gas relative to other energy sources. When gas prices are lower than the parity prices of alternatives such as coal, oil, or renewables, natural gas becomes a more attractive option for consumers, driving higher demand. However, if gas prices rise significantly, consumers may shift to more cost-effective alternatives, thus reducing the market share of natural gas. 2024 marked a period of stabilization for spot gas prices, offering a sharp contrast to the extreme volatility witnessed over the previous four years, which saw both record lows and highs. In 2025, global spot gas prices are expected to rise, driven by sustained growth in global gas demand, projected at 2 %, and a positive economic outlook, with global GDP growth forecasted at over 3 %. Contributing factors include a shift from coal to gas, increasing power generation needs, recovering industrial activity, and higher heating demand due to colder-than-usual winters across various regions. In 2026, the market is expected to loosen as LNG liquefaction projects commissioned in 2025 ramp up production, and an additional 57 Mtpa of capacity comes online.
Editorial
Heiko Woizick
Head of Power Plant Chemistry RheinEnergie AG , Cologne, Germany
Chairman of the vgbe Technical Committee Chemical Process Engineering and Analytics
Challenges for Power Plant Chemistry due to the “Energie- und Wärmewende”
Dear readers of the vgbe energy journal,
The ever increasing speed of the energy and heat turnover has a great impact on power plant chemistry. While the decommissioning of more and more coal- and lignite-fired power plants is reducing the analyses of fuels, ashes and the classic power plant by-products, new technologies are also creating new challenges for power plant chemistry.
Gas-fired and combined-cycle power plants, which will still be needed in the long term, are being used more and more flexibly. The monitoring, conditioning and preservation of the water-steam cycles of combined cycle power plants must therefore be adapted. How can steam purity be achieved more quickly at plant start-up and measured reliably? Does the conditioning of the water-steam cycle have to take into account the increased material stress caused by the higher load gradients? How do you maintain the plants when you do not know exactly how long they will be out of service, but you have to be ready to start them up at short notice?
In the future, gas-fired power plants will increasingly run on hydrogen, which will place new demands on the materials used. The chemical industry has been working with hydrogen for decades. The knowledge gained in the handling of hydrogen should be used in the construction of hydrogen networks and in power plant technology. It will be necessary to examine exactly what needs to be adapted for power plant technology.
The hydrogen for the new networks must also be produced in a climate-neutral way. Worldwide, ever larger electrolysis plants are being planned, the first are being built and some are already in operation. The three main processes used are alkaline electrolysis (AEL), proton exchange membrane electrolysis (PEM) and high-temperature electrolysis with SOE (solid oxide electrolysis) stacks. These electrolysis processes have different water purity requirements. In some cases, these go well beyond the requirements for demineralised water for power plant operation. For this reason, Data Sheet M407 (Design, specification and performance verification of water demineralisation systems) is currently being revised and expanded. It will also include information on the use of materials in contact with this high-purity demineralised water. Various operational experiences show that there is a need for research, whether due to corrosion or the release of undesirable substances. The experience of the first operators is particularly important in this respect.
In the context of heat transfer, large heat pumps are currently being installed at many power plant sites. In some cases, copper heat exchangers are used that are in contact with the district heating water, but it is not clear whether the copper is resistant in the long term, or whether the traces of copper released into the district heating water will cause corrosion in the district heating network. It should be discussed and investigated whether the slightly more expensive and larger stainless steel heat exchangers are not the better choice in the long term.
Many operators are currently planning and building sewage sludge mono-incinerators to recover the phosphorus in sewage sludge, which will be mandatory from 2029. The first plants are already in operation and pose new challenges for power plant chemistry. The vapour condensate produced is usually still disposed of at great expense. The alternative, treatment, is costly and still causes major problems in operation. In the long term, new plants will comply with lower limits for mercury in flue gas and wastewater, and flue gas cleaning by flue gas desulphurisation (FGD) is planned, but on a smaller scale. The experience gained from the large coal-fired power stations that will be shut down in the near future can be used here.
All this is happening at a time when, as coal-fired power stations are shutting down, many power station laboratories are being closed and the people who know the chemical processes are often being sent into early retirement. Their expertise will be sorely missed.