Good thinking nFnG. The air ships of old used water as ballast for bouyancy control. I'm sure Vern & the boys are thinking the same way. So if you've got some water on board you've got the potential to make your own lifting gas or fuel to feed a fuel cell. I'll bet they are planing on using both of PROTONs products (in SANSWIRE 2). I know LockMart is.
Now here in lies the tough part. One of the most memorable mechanical disasters (in fact the first one captured on film) was the crash of the Hindenberg. I call that event the "H factor". It burned an indelible image into the public's mind concerning the use of hydrogen. To this day no one in airship development wants to imply that they use anything but helium. The "H factor" has to be overcome for airships to reach the altitudes and endurance the GTEL business plan & anxious broadband customers will demand.
PROTON's systems have been successfully deployed way up in space. When you park that "H factor" 13 miles above a populated area you are inviting the Chicken Little's to make all kinds of assumptions. I trust GLOBETEL & NASA will work out the details.