Like JackBean posted, energy transfers into some other type and is lost from the system (100% efficiency is not obtained in the stated system). Thus, the original energy for cycling is not obtained for the system. In order to continue the cycle, input of energy needs to be obtained.
hmm from this i have a question i think the energy is cycled.
what happenes to the energy that has been lost?
it cant be destroyeed nor do i think that its lost to the space for heat needs a medium to travel.
hmm i think it must be being recycled somewhere.
for example if we say all the heat lost to the environment is being used to evaporate water.
maybe it may be being used in some other reaction in the atmosphere maybe for the formation of ozone (though thats unlikely)
but the main thing remains that energy lost as heat must be being recycled or being used
