Efficiency is pretty lousy. But sometimes you don't want to lug around a compressor, like inside a portable device (such as a food cooler, portable computer, or even a prosthetic limb). In that case inefficient is often better than nothing.

But also if this is an indication that more research effort is going into this because of breakthroughs, that’s a good thing. Double the efficiency a few more times and pretty soon it could be competitive in many uses.

Solar panels used to be horrible at efficiency. Now they’re pretty amazing and extremely competitive in the power generation market. It, similarly, took a few decades of these kinds of efficiency improvements to get there.