Sustainable, highly efficient and easy to regulate: as a heat transfer medium, steam has numerous advantages for industry and is used in a wide range of industrial processes in various sectors. In addition, water is generally available as a reliable and cost-effective resource. However, in many cases, energy from the utilisation of fossil fuels is still used to generate steam. In order to reduce their own emissions, more and more industrial companies are therefore looking for ways to decarbonise their process steam. The solution: power-to-steam – the conversion of green electricity into process steam. In combination with thermal energy storage, electricity from renewable sources can be stored and made available for steam generation when required.
Power-to-steam: the basics and how it works
Typically, the process of steam generation begins with the combustion of fossil fuels such as natural gas, coal or oil in order to heat water with the released heat energy. The heated water is pressurised, which raises the boiling point of the water and converts it into steam. Power-to-steam makes it possible to generate industrial process steam sustainably and efficiently. The process is based on the conversion of surplus green energy, such as wind or solar, into steam. The green electricity is used to split water into hydrogen and oxygen using electrolysis. The hydrogen produced is then burnt in a steam generator, releasing thermal energy to heat water and convert it into steam.
An innovative alternative is the use of thermal energy storage systems such as the ThermalBattery™ from ENERGYNEST, which store renewable electricity in the form of thermal energy or steam and release it directly as process steam when required or use the thermal energy to heat water and convert it into steam.
Green process steam with thermal energy storage: advantages for industry
Process steam is still used today in a wide range of industrial applications in various sectors. It can either be used to drive rotating machinery with the help of steam turbines or used directly – for example for drying, distillation and sterilisation.
In the food and beverage industry, process steam is used to clean and sterilise process plants and containers such as glass bottles in order to ensure safe and hygienic production. In the chemical industry, process steam is used as an energy source for reaction processes and for the distillation of chemicals. Steam is also used in the pulp and paper industry to power paper machines and soften fibres during the production process. By using green energy instead of fossil fuels to generate process steam, these companies can make a crucial part of their production more sustainable.
Reduction of CO2 emissions
By switching to green process steam, companies can significantly reduce their CO2 emissions. This not only drives the effective decarbonisation of production processes, but also protects companies from unpredictable price fluctuations, potential supply shortfalls and additional costs such as CO2 certificates by switching to decentralised renewable energy sources.
Reduce operating and energy costs
In addition to improving their environmental footprint, switching to power-to-steam with green energy also pays off economically: companies have the opportunity to significantly reduce their operating and energy costs. By using renewable energies to generate steam, companies become independent of expensive fossil fuels. In addition, the decentralised generation of process steam on site enables an increase in efficiency, as losses due to transport are avoided.
Using green energy more efficiently
The integration of thermal energy storage systems into the production of green steam also enables the optimal utilisation of available energy by storing surplus electricity and making it available when needed. This allows companies to react flexibly to fluctuating availability and ensure the security of supply for their processes at all times.
Sustainable power-to-steam solutions with ThermalBattery™
To convert low-cost renewable electricity into green process steam using the ThermalBattery™, companies can choose between two options for integrating the heat storage system, depending on the design of their plant and the available energy source. Option 1 converts green energy into heat by heating thermal oil in a resistance heater to charge the ThermalBattery™. The heat is stored with minimal losses and retrieved later when required to feed it into the steam generator. In option 2, the ThermalBattery™ is charged directly using steam from the e-boiler, which is also powered by renewable electricity. The stored steam can then be accessed as needed to directly supply steam. Both approaches enable the flexible and sustainable use of renewable electricity for steam generation and help to improve the efficiency and environmental friendliness of industrial processes.
