It is essentially a conventional dehumidifier.

While military applications actually may be one of the few areas where some "green" technologies like PV solar could be truely appropriate, I don't see any solar panels on those tanks. I haven't run the numbers based on their stated water output, but to run a smallish compressor you'd need at least a few square meters of panel.

One sniper (or "suicide rock thrower") takes out your water source.

However, there is still an advantage of having the option to convert diesel fuel into water.