Being able to cool a beverage below the room temperature is quite a challenging problem. The major challenge is the energy inefficiency of any cooling system, which tends to be in the range of 2% to 7%, under the described conditions. On a Peltier device, this issue manifests in the form of excess heating. If the hot-side of the plate is not kept at a low enough temperature, through heat dissipation, the cooling effect of the device is never observed.
The Nordics came up with a "Heat Exchanger" design that can achieve the desired heat dissipation as well as an effective contact of the cold-side of the plate with the beverage cup. The image below shows the mechanical design of the heat exchan
ger.