Economic Aspects of the Magnetocaloric Energy Conversion - Magnetocaloric Energy Conversion: From Theory to Applications - page 376

CHFkWh − 1 ) for the best-case scenario and large-scale magnetocaloric power
generation of 15 MW.
An additional study was performed in 2010 by Egolf et al. [ 29 ]. This time central
magnetic chiller applications were studied (see also Kitanovski et al. [ 35 ]). For the
purpose of the study the authors designed three different magnet assemblies for rotary
magnetic chillers, with three different magnetic elds (1, 1.5 and 2 T, respectively).

The design of such a magnet assembly can also be seen in the chapter on magnetic

eld sources (Chap. 3 ), Fig. 3.33 . Since the design was such that it enabled up-scaling
of the magnet assembly for different applications (related to cooling power), this also
provided a good basis for further technical and economic evaluation. In all the
analyses the coldest point of the magnetocaloric material was de ned to be 7 ° C and

the hottest point was de C (i.e. 25 K difference between the heat source

and the heat sink). These two temperatures were compared with the temperatures of
the chilled and the cooling

ned to be 32 °

uid at the outlet of the evaporator and the outlet of the
condenser, respectively. For these data, a COP = 5.5 for the compressor chiller was
de

fl

cient of
performance was also the basis on which the further economic analysis was per-
formed. For the purpose of the study, the thickness of the magnetocaloric plates in the
regenerator was one of the main parameters. This was varied from 100 to
400 microns. Also, the volume fraction of the magnetocaloric material in the
regenerator was varied from 30 to 60 %. Two working fluids were evaluated, the 20 %
ethanol water solution and the liquid metal Galinstan (see Sect. 4.6 ). The latter was
chosen because of its good heat transfer characteristics.
Figure 9.12 was constructed using data from Egolf et al. [ 29 ]. It shows the
manufacturing cost ratio between a magnetic chiller based on the AMR principle,
and an equivalent compressor chiller for two different working

ned as the minimum required value for the magnetic chiller. This coef

uids. In the case of
water-ethanol, this corresponds to a range of cooling powers up to 8 kW. In the case
of Galinstan, this corresponds to cooling powers up to 30 kW. Note that for the

fl

Fig. 9.12 The ratio between the manufacturing costs for the AMR-based magnetic chiller with
permanent magnets and the equivalent compressor chiller for two different heat-transfer fl uids

(calculation performed on the basis of data from Egolf et al. [ 29 ])