Recirculate cockpit air to keep feet warm?

As we know, flying in wave with the sun shining, much of the cockpit stays reasonably warm, but the feet, down in the shade, get cold. So, as I'm here at home on a cold night with a fan helping distribute the heat from the wood stove to another room, it occurred to me that something like that may be possible in the cockpit? A small fan (using a fraction of the electric power that the typical instrument panel uses), perhaps with a short duct, could move sun-warmed air towards the feet. Has that been tried? Does it help? Would it use more electrical power than electrically heated insoles?

Back when I flew an HP-14 which had a canopy that extended forward over the rudder pedals, my feet were much warmer in cold but sunny weather than they are in my current glider. As long as I was pointed towards the sun, that is - typically pointed into a West wind in the afternoon. As soon as I turned around to the East the cockpit temperature plunged.