Sven-Olaf Klüe has been working in the field of design, manufacture and applications of pillow plate heat exchangers worldwide for 27 years. For the past 15 years, he has focused specifically on the process-related applications of pillow plate heat exchangers in industrial applications.
Industrial ice banks in combination with heat pumps
An energy efficiency saving for the industry with sustainability
For decades, ice banks have been used as energy storage in refrigeration systems. However, now there is a new and interesting use, that ice banks are also utilized as heat sources for heat pumps.
In an ice bank heat pump, a thermal storage unit at a low temperature is used as the heat pump's source. Freezing the water in the storage unit releases a significant amount of heat, which keeps the source temperature close to zero even at low outdoor temperatures. As a result, the heat pump's efficiency is higher than that of air heat pumps in cold temperatures.
Industrial ice storage is an innovative solution for companies to store surplus energy in the form of cold and use it later. Significant energy savings can be achieved by combining ice banks with heat pumps. This method is particularly suitable for industrial processes or heating of buidlings, where a high energy demand is required for production. The use of fossil fuels or electric heating systems can be costly and pollute the environment. Alternative solutions such as the use of ice storage are not only more energy efficient, but also more environmentally friendly. Companies that want to rely on innovative technologies and operate more sustainably should consider the use of industrial ice storage.
One significant way to increase energy efficiency in industry is to use industrial ice storage in conjunction with heat pumps and energy-efficient technology. By implementing such solutions, we can reduce our dependence on harmful fossil fuels and focus on effective alternatives that protect our environment. Companies that implement these measures will not only reduce their operating costs, but also make a positive contribution to the environment and generate long-term benefits for their businesses.
Explanation of the individual components of efficiency
What are industrial ice banks and their energy efficiency?
An ice bank heat pump system utilizes a low-temperature latent heat storage on the source side to store and supply ambient heat to the heat pump. The frozen water releases a significant amount of stored heat at a constant temperature. Freezing water releases roughly the same amount of heat as cooling from 80°C to 0°C (335 kJ/kg or 93 Wh/kg).
An ice bank heat pump is an efficient and versatile heat pump system. It employs a low-temperature latent heat storage to store heat at a constant temperature. The main components include a brine/water heat pump, an ice bank, solar collectors or absorbers, and a heat storage unit. It can utilize solar heat, ambient air, and geothermal heat as heat sources based on demand. Various operating modes and combinations of heat sources, ice bank, and heat pump are available. Maximize your energy efficiency with an ice bank heat pump system.
Different renewable heat sources or waste heat can be used for regenerating the ice bank. In practice, ice bank heat pump systems are often combined with solar collectors or absorbers to charge the ice bank. This is achieved through a combination of solar heat, ambient air, and heat transfer from the ground. Depending on the concept, solar heat and ambient air can even be directly used as heat sources for the heat pump. Solar heat can be directly utilized with solar collectors. Ice bank systems are an alternative to air-source heat pump systems and can be used where ground source boreholes are not feasible. The integration of solar collectors into heat pump systems without an ice bank is already widely adopted.
Industrial ice storage is an innovative solution for energy generation and storage. The principle of phase change heat makes it possible to store large amounts of energy and make it available when needed. By freezing water during cheaper energy prices or at times when the energy supply is less stressed, the stored cold can be used during the day or when needed. This offers companies great flexibility in their energy supply and helps to reduce costs. Industrial ice storage is therefore not only a sustainable alternative, but also an economically sound investment. Especially in summer, when energy costs and demand are higher, the ice in the ice storage is used to meet the cooling needs of the industrial process.
The Ice Bank
The ice bank serves as a heat storage with water as the medium in conjunction with ice bank heat pumps. In this process, the energy absorbed during the transition from ice to water and released during the conversion from water to ice (latent heat) is used as storage. As a result, a large amount of heat can be stored with a small temperature difference. The phase change in the ice bank occurs at 0°C. The complete melting of 1 kg of water requires the same amount of heat as heating 1 kg of water from 0°C to 80°C. This so-called enthalpy of fusion or heat of fusion is 335 kJ/kg or 93 Wh/kg for water.
The evaporator of the heat pump/chiller is directed into the ice bank. Blowing air at the bottom of the tank or circulating it ensures that ice growth occurs evenly on the heat exchange surface. The thickness of the ice on the heat exchange plates is controlled and regulated by an ice thickness gauge.
The Heat Pump
Ice bank heat pump systems use heat pumps with a brine circuit. The source temperature can vary significantly depending on the operating mode and weather conditions (usually between -10°C and +25°C). For this reason, heat pumps must be used that can operate efficiently at different temperature differentials. This aspect of the requirements is similar to that of air-to-water heat pumps. The operating range of the heat pump evaporator and the maximum temperature of the ice bank must be coordinated, or the inlet temperature to the evaporator must be regulated by a mixing valve.
The Heat Storage
Thermal heat storage optimizes the runtimes of the heat pump and enables the handling of peak loads. In addition, the use of the auxiliary heater can be delayed or avoided during periods of low source temperature. The heat storage does not need to be specially adapted for ice bank heat pump systems; standard products can be used.
The Solar Collectors/Absorbers
Thermal solar collectors lose efficiency as the collector temperature rises, as heat losses increase. The solar efficiency also depends on solar radiation. Higher radiation means better efficiency. Different measures can be taken to reduce heat loss in order to achieve high efficiency at higher collector temperatures. However, higher temperatures and desired higher efficiency increase both the effort and the costs for the collector.
How do industrial ice banks work?
The evaporator plates are placed upright in a rectangular or round water tank and form ice at an evaporation temperature between -4 and -10 °C. This ice remains static on the evaporator plates. This remains statically attached to the evaporator plates and is evenly distributed by water running back to the bottom of the tank via a distribution system. In addition, a special distribution system ensures intensive swirling of the air to guarantee perfect heat transfer and low ice water temperatures. This is particularly important to ensure continuity in ice production. The automatic start-up of the air circulation only when needed also ensures more efficiency and energy savings.
Unlike other energy storage systems, such as batteries, ice storage systems are very durable and have a high storage capacity. They can also be installed quickly and easily and require only low maintenance costs.
Efficient cooling is of great importance for many companies. Especially in industries such as food production or pharmaceuticals, maintaining low temperatures is essential to ensure the quality of the products and thus the trust of the customers. With the technology of an almost constant ice surface until the end of the cooling phase, maximum cooling performance is achieved at the lowest ice water temperatures. In this way, companies can ensure that their products are always delivered in the best possible quality.
How does a heat pump work?
Heat pumps are an excellent option for heat generation and use, as they can absorb heat energy from various sources and bring it to higher temperatures in no time. The principle of operation is similar to that of a refrigerator, with the difference that the heat absorbed is used to heat buildings or processes. There are numerous ways to operate heat pumps, such as by using the ambient air, the ground or groundwater. With a view to sustainable and efficient heat production, the use of heat pumps is a smart option.
What Is a Heat Pump?
A heat pump is an innovative technology that allows heat energy to be efficiently transferred from a place with a lower temperature to a place with a higher temperature. This device is particularly successful in industrial use, as it provides a sustainable and emission-free way to use the heat from the ice storage and transfer it to the cooling system of the industrial process. A heat pump can extract energy from the ambient air, groundwater or geothermal heat, making it a renewable energy source. Unlike conventional heating systems, which are based on fossil fuels and pollute the environment, the heat pump is an environmentally friendly option that offers economic and operational advantages at the same time.
Combination of industrial ice banks and heat pumps as sustainable energy efficiency
How can industrial ice banks be combined with heat pumps?
Combining industrial ice storage with heat pumps offers an efficient way to generate energy in the form of heat. With the help of heat pumps, the stored cold energy can be converted into usable heat energy during the warm season. In doing so, the system is not only energy-efficient and environmentally friendly, but also offers an economical alternative to traditional heating systems. Especially for companies that focus on sustainability, this technology is an interesting solution to save costs and at the same time contribute to climate protection.
What is the Energy Efficiency Hub and why should countries join it?
How can the combination of industrial ice storage and heat pumps contribute to energy savings?
Combining industrial ice banks and heat pumps is a promising way to reduce energy consumption in industry. This method uses surplus energy to fill the ice storage, which is then used to generate thermal energy when it is needed. Thanks to this innovative technology, industrial companies can effectively counteract their energy consumption while also reducing their CO2 emissions. Companies that want to underline their commitment to sustainability and environmental sustainability should therefore consider this advanced technology.
Using industrial ice storage in combination with heat pumps is an extremely effective way to save energy and significantly reduce a company's energy needs. By using surplus energy in the form of cold to generate heat, considerable progress can be made in energy efficiency. In fact, by combining ice storage and heat pumps, businesses can save up to 50 per cent energy compared to traditional heating and cooling methods. Investing in a company's energy efficiency in this way can help reduce costs, protect the environment and improve the company's image.
Industrial production is an important part of our modern world, but it requires an enormous amount of energy. Traditionally, this energy is derived from fossil fuels, which is unfortunately both expensive and harmful to the environment. For this reason, companies are looking for new and advanced ways to lower their energy costs while reducing their carbon footprint. One promising technology for this is the combination of industrial ice storage with heat pumps. This can not only save energy, but also produce more sustainably - an important step towards a cleaner and more efficient future.
Will a heat pump lower my energy bills?
Ice banks in combination with heat pumps offers numerous advantages for the industry:
The terms coefficient of performance and performance ratio are often used interchangeably. They refer to the ratio of heat produced to the end energy input over a specific period, such as one year.
In the context of a complete heat balance, the coefficient of performance is always less than one. Due to conversion and heat losses, the actual utilized energy is always lower than the end energy input. However, in the case of heat pumps, the environmental energy is usually not taken into account as it is freely available. The coefficient of performance is only calculated based on the electricity consumption. Hence, the coefficient of performance is usually above one.
Ice bank heat pumps with additional solar collectors are more efficient than air/water heat pumps and can achieve the same performance ratio as ground source heat pumps when used properly. They are a sensible choice for energy-efficient heating, especially in cases where ground source drilling is not feasible. Ice bank heat pumps with large collector areas and parallel integration have the potential for a higher performance ratio compared to ground source heat pumps. This technology is still relatively new, but there is still potential for improving the performance ratio through the optimization of the ice bank, controls, and components.
- Energy savings: Ice storage allows for cost-effective storage of energy while energy prices are lower. This stored energy can then be used to meet the cooling needs of the industrial process. This reduces the energy demand of the industrial process and lowers energy costs.A big advantage of this technology is that it is very efficient. Heat pumps can generate up to four times more thermal energy than they consume electrical energy. Since ice storage can store thermal energy at a very low temperature (down to -8°C), it is possible to generate thermal energy with a high level of efficiency. Thus, by combining industrial ice banks and heat pumps, a significant amount of the total energy required can be saved,
- Environmentally friendly Ice storage in combination with heat pumps reduces CO2 emissions and is therefore more environmentally friendly than conventional systems. By using renewable energies such as ambient air or geothermal heat, the environment is protected. The combination of ice storage and heat pumps is environmentally friendly. Since less energy is needed to cool the production facilities, less CO2 is emitted.
- Efficiency: The combination of ice banks and heat pumps enables a higher efficiency of the industrial process. The cooling systems can be operated at a higher efficiency and thus the energy demand is reduced.
- Long-term cost savings: Although the investment costs for installing an ice bank system and a heat pump can be higher than for conventional heating systems, these systems lead to significant cost savings in the long run. The advantage of this combination lies in the energy savings. Since the ice is produced at night when electricity is cheaper and used when it is needed, the company can optimise its electricity consumption and save costs. As the heat pump is also a renewable energy source, the company can reduce its CO2 emissions and produce in a more environmentally friendly way.
Industrial ice banks combined with heat pumps has become a promising technology in the energy saving market. By using cheap electricity and renewable energy sources, the company can reduce its energy costs and at the same time reduce its CO2 emissions. Companies that try this technology will not only save money, but also make an important contribution to environmental protection. Last but not least, it will help you position yourself as a targeted brand and be perceived as a company that is actively and sustainably committed to protecting the environment.