Heck I think it's a great idea and may very well do the same thing myself. BTW, depending on the thickness of the walls and their R (insular) value, holding a room to a max of 20 C, which is fine for even moderately long term storage (up to 10 years or so) should be very fine indeed. Wineries LIKE to keep barrel rooms at 16 C or less and bottle goods warehouses at 18 C or less, but in fact many here in Israel do not reach those goals. As a consumer 20 C is fine. IMO regularity of temp is more important than keeping wine so cool that you actually retard development - although slower development, chemically, leads to more complexity eventually.
Well as I age too I'm less interested in wines that will last 20 years or more