Honest limits

The leftover from the membrane is brine: saltier water you still have to put somewhere without killing the harbor floor. Membranes clog and need cleaning. Pumps need parts. Noon hours are not midnight.

A field of panels does not by itself make a drink. A town can cover the last pasture and still send brackish water if the cheap hours never reach a pump.

This lesson is not about who owns the night storage. Storing power can matter later. The invent here is attaching cheap daytime power to a cup.

It is also not a farm ban, a 100-percent poster, or a still in a garage.

The limits are the plant’s edges, not a reason to leave it idle at noon.

The tempting mistake is to think that once the salt is out, the problem is gone. The brine has to go somewhere.

That is what lets you invent the cup.