A combustion engine including a combustion chamber, a first bleed air supply, a second bleed air supply, a thermal bus and a turbomachine. The first bleed air supply being fluidly coupled to a first fluid from a portion of the combustion engine upstream of the combustion chamber. The second bleed air supply being fluidly coupled to a second fluid portion of the combustion engine downstream of the combustion chamber. The turbomachine having a compressor and a turbine. The compressor being fluidly coupled to the first bleed air supply. The turbine being fluidly coupled to the second bleed air supply.