Aluminium cannot be used to reinforce regular concrete since the high pH will attack the metal and evolve hydrogen gas. However, Al/5%Mg alloy is stable in concrete where 55% cement is replaced with calcined clay in the concrete mix. Replacing high fraction of clinker burnt at 1450ºC, and with high CO2emission from limestone decomposition in the raw meal, with a clay calcined at 850ºC obtainable by biofuel give obvious savings in energy and CO2 emissions. Furthermore, since aluminium can withstand carbonation and chlorides a cover of only 20 mm for mechanical interaction with reinforcement is needed resulting in a smaller concrete volume. Binder with 55% calcined clay is sulphate resistant and do not induce AAR due to lower pH and no remaining calcium hydroxide in the system. The only degradation mechanism left is freeze-thaw avoidable by proper air entrainment. Thus, in theory an infinite service life without maintenance may be at hand for aluminium metal reinforced concrete.