Apparatuses, methods and storage medium associated with coolant systems for computer and electrical environments are disclosed herein. In embodiments, an apparatus for selectively transferring of heat within a computer environment may include a cold plate thermally coupled to a liquid line of a liquid coolant system of the computer environment, the cold plate to transfer heat to the liquid line and a thermally-conductive body to cool a component of the computer environment. The apparatus may further include a thermoelectric cooler (TEC) thermally coupled with the cold plate on a first side of the TEC and thermally coupled with the thermally-conductive body on a second side of the TEC, the TEC to increase an amount of heat transfer from the second side of the TEC to the first side of the TEC in response to energy provided to the TEC.