The issue is you can’t cool on air alone, it doesnt work well enough due to radiant heat still transferring to the tire

IIRC the rules cap MGUK torque to 200 Nm at the crankshaft (when 120 kW action is desired but crankshaft rpm is low)autodoctor911 wrote: ↑20 May 2025, 12:16What is limiting the amount of braking force applied to the rear wheels via mgu-k application of regenerative braking???
the correspondence is fascinating as it offers us the first proper insight from a competitor about theories on what McLaren could have been up to and what the FIA thinks about some of these design ideas the race has seen a copy of this technical directive which includes a host of questions from Red Bull about design ideas and procedures relating to tire cooling plus some responses from the FIA on what it thinks is and isn't allowed
a design could incorporate having such Peltier devices fitted somewhere within the assembly that could then be used to cool things down or even heat things up with there being no moving parts on a Peltier device. it conforms to the technical rules that require everything to be rigidly attached to the upright. the FIA's response on the idea of using such a solid state thermoelect electric cooler is intriguing. the FIA's answer says "We believe that the use of Peltier devices for cooling in this area is not covered by the technical regulations but would not consider it favorably and would seek to specifically exclude it for 2026
Peltier will be a generator when heated on one side and the other side naturally getting colder. The electricity generated at the junction will need to be dumped somewhere.