We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Tim Lamb
saying something like:

There is an energy input, but I really doubt it could be made large
enough to compress all that air, and afaics, the lifting bodies would be
far too small.
I'd not be surprised if a man-lifter using the idea could be built, but
for larger scale use, probably not.

er.. my understanding was that the energy for compressing the gas comes
from turbines powered by airflow. Unless there is some way to initially
power the pump at altitude, there will be no airflow as the device is at
equilibrium WRT the atmosphere.

The energy input I refer to is the turbine(s), but I can't see it
working from start height without some battery power onboard.
I'd be quite happy to be proved wrong - if it can be made to work on a
small scale it would be a hoot.