Skip to main content
To KTH's start page

Magnetic Refrigeration

Although Magnetic refrigeration is a well-known method in cryogenics, it has not been commercially used at room-temperature. In this project, the possibilities with and the potentials of magnetic refrigeration system are investigated to find the most suited application for commercializing the technology.

Aims of the project

Many magnetic refrigeration prototypes with different designs and software models have been built in different parts of the world; nevertheless, there are still challenges in the way of commercialization of magnetic refrigerators. The obstacles hindering commercial production of room temperature magnetic refrigeration are both economic and technical. In this project, the possibilities with and the potentials of magnetic refrigeration system are investigated to find the most suited application for commercializing the technology.

This Project is a part of EFFSYS EXPAND , a program established by The Swedish Energy Agency, Energimyndigheten

Publications

The articles (full text) can be downloaded by clicking on their titles:

MAGNETIC VS. VAPOR-COMPRESSION HOUSEHOLD REFRIGERATORS: A PRELIMINARY COMPARATIVE LIFE CYCLE ASSESSMENT

Monfared, B., Furberg, R., and Palm, B., 2014, "Magnetic vs. vapor-compression household refrigerators: A preliminary comparative life cycle assessment," International Journal of Refrigeration, 42(0), pp. 69-76. doi: 10.1016/j.ijrefrig.2014.02.013 .

OPTIMIZATION OF LAYERED REGENERATOR OF A MAGNETIC REFRIGERATION DEVICE (pdf 3.1 MB)

Monfared, B., and Palm, B., 2015, "Optimization of layered regenerator of a magnetic refrigeration device," International Journal of Refrigeration, 57, pp. 103-111. doi: 10.1016/j.ijrefrig.2015.04.019 .

SIMULATION OF SOLID-STATE MAGNETOCALORIC REFRIGERATION SYSTEMS WITH PELTIER ELEMENTS AS THERMAL DIODES (pdf 1.3 MB)

Monfared, B., 2017. "Simulation of solid-state magnetocaloric refrigeration systems with Peltier elements as thermal diodes." International Journal of Refrigeration, 74, pp. 322-330. doi: 10.1016/j.ijrefrig.2016.11.007 .

DESIGN AND OPTIMIZATION OF REGENERATORS OF A ROTARY MAGNETIC REFRIGERATION DEVICE USING A DETAILED SIMULATION MODEL (pdf 2.0 MB)

Monfared, B., 2018. "Design and optimization of regenerators of a rotary magnetic refrigeration device using a detailed simulation model." International Journal of Refrigeration, 88, pp. 260-274, doi: 10.1016/j.ijrefrig.2018.01.011 .

MATERIAL REQUIREMENTS FOR MAGNETIC REFRIGERATION APPLICATIONS (pdf 1.4 MB)

Monfared, B., and Palm, B., 2018. "Material requirements for magnetic refrigeration applications." International Journal of Refrigeration, doi: 10.1016/j.ijrefrig.2018.08.012

Background information

Although Magnetic refrigeration is a well-known method in cryogenics, it has not been commercially used at room-temperature. Brown built the first prototype magnetic refrigeration device working at room temperature in 1976. Since Brown’s successful experiments, an increasing number of prototypes have been built. Currently an increasing number of researchers are working on developing prototypes, models predicting the performance of the magnetic refrigerators, and materials used as refrigerant in magnetic refrigerators.

Working principle

The working principle of magnetic refrigerators is based on magnetocaloric effect, perceived as adiabatic temperature change or isothermal entropy change. Some materials show a significant temperature change when they are exposed to an external magnetic field. When the process of magnetizing is done adiabatically the magnetocaloric effect is observable as adiabatic temperature change, ∆Tad. However, if the heat is removed from the material to keep the temperature constant while the external magnetic field increases, the effect is seen as entropy change. 

For a magnetocaloric material at thermal equilibrium with its surroundings, the increase in the external magnetic field in an adiabatic process results in an increase in the temperature of the material. Because of being at higher temperature, the magnetocaloric material can exchange heat with its surroundings to approach the surroundings’ temperature. After the heat transfer process, if the external magnetic field is reduced the temperature of the magnetocaloric material will drop below the temperature of the surroundings, and therefore, the cooling effect can be used for refrigeration purposes. There is an analogy between the magnetic refrigeration cycle and conventional cycles, esp. Joule-Brayton cycle. The analogy is shown graphically in the diagram.

Experimental investigations to maximize efficiency of CO2 vapor compression systems
Sustainable Geothermal Energy for the Future: AI in ATES
Warm water systems, losses and Legionella
PARMENIDES – Plug & plAy EneRgy ManagEmeNt for hybriD Energy Storage
HYSTORE - Hybrid services from advanced thermal energy storage systems
Open-source models for holistic building energy system design at scale
Tank to Grave Management of new Low-GWP Refrigerants (Hantering av nya låg-GWP köldmedier från installation till destruktion)
Novel tool and guidelines for designing ground source heat pumps (GSHPs) in densely populated areas
Data driven lab for building energy systems
Long-term performance measurement of GSHP systems serving commercial, institutional and multi-family buildings
Open-source models for holistic building energy system design at scale
Control systems for hybrid solutions based on biomass fueled Stirling engines, solar and wind for rural electrification
Prosumer-Centric Communication for Solar PV Diffusion (completed)
Towards Sustainable (Fossil-free) Heating System in Small Residential Buildings
Solar energy and ground source heat pumps for Swedish multi-family housing (completed)
Solar photovoltaic systems in Swedish cooperative housing (completed)
Smart Control Strategies for Heat Pump Systems (completed)
Creating and Understanding Smart Innovation in Cities
Building heating solutions in China
Accelerating innovation in buildings
High-Resolution GIS District Heating Source-Load Mapping
Digitalization and IoT technologies for Heat Pump systems
Sustainable combined systems for heating of buildings (completed)
Cost- and Energy-Efficient Control Systems for Buildings
Situation of Opportunity in the Growth and Change of three Stockholm City Districts (completed)
Wuxi Sino-Swedish Eco-City Project (completed)
Smart Renovation Strategies for Sustainable Electrification
Future Secondary Fluids for indirect refrigeration systems
Smart Fault Detection and Diagnosis for Heat Pumps
Performance indicators for energy efficient supermarket buildings
Magnetic Refrigeration
High-Resolution GIS District Heating Source-Load Mapping
Smart Solar Hybrid Solutions for Sustainable European Buildings (completed)
Building state-of-the-art (SotA) supermarket: Putting theory into practice
Efficient utilization of industrial waste heat by low temperature heat driven power cycles – an integrated approach for Swedish Industry
Cooperation between Supermarkets and Real Estate Owners; Energy Efficiency and Business Models
Digitalization and IoT technologies for Heat Pump systems
Capacity control in Heat Pump systems
Alternative secondary fluids
Functional surface coatings for energy efficient heat pumps
Two-phase flow in flat channels
Two phase heat transfer & pressure drop with new environment friendly refrigerants in minichannels (completed)
Numerical Study on flow boiling in micro/mini channels (completed)
Distributed Cold Storages in District Cooling
Integrating Latent Heat Storage into Residential Heating Systems
Simulation of temperature distribution in borehole thermal storages supported by fiber optic temperature measurements (completed)
Solar energy and ground source heat pumps for Swedish multi-family housing (completed)
Neutrons for Heat Storage, NHS, (completed)
4D Monitoring of BTES (completed)
Aquifer Thermal Energy Storage (completed)
Deep Borehole Heat Exchanger (completed)
Combined Heat and Power plants in combination with borehole thermal energy storage (completed)
Improved borehole technology for Geothermal Heat Pumps development (completed)
Compact Minichannel Latent Energy Storage for Air Related Cold Storage Applications
Building heating solutions in China
Toward Sustainable (Fossil-free) Heating System in Small Residential Buildings
Renewable Energy Park, RE-Park (completed)
Efficient use of energy wells for heat pumps (completed)
Efficient design of geothermal heating systems (completed)
SPF (completed)