  A three-stage metal hydride hydrogen compressor (MHHC) system based in
AB2-type alloys has been set-up. Every stage can be considered as a
Sieverts-type apparatus. The MHHC system can work in the pressure and
temperature ranges comprised from vacuum to 250 bar and from RT to 200C,
respectively. An efficient thermal management system was set up for the
operational ranges of temperature designed. It dumps temperature shifts due to
hydrogen expansion during stage coupling and hydrogen absorption/desorption in
the alloys. Each reactor consists of a single and thin stainless-steel tube to
maximize heat transfer. They are filled with similar amount of AB2 alloy. The
MHHC system was able to produce a compression ratio (CR) as high as of 84.7 for
inlet and outlet hydrogen pressures of 1.44 and 122 bar for a temperature span
of 23 to 120C.
