Yup, what other person said, heat pump dryers.
They use the insides of the dryer as the closed loop of heating and cooling. Heating air through clothes to get moisture then cooling it on the other side to condense it. Generates water but doesnt have a vent.
Neat use of the tech.







I pull an all nighter every 6 months. Its fun and the delusional day after is even better/worse.