I can responsibly say: Yes.
Reason: Our teacher said so.
Deeper reason: Most power plants use thermal energy to produce electricity. The principle is primary battery, that is, the process of burning carbon to generate carbon dioxide generates electricity through the transfer of electrons. But most of them don't use pure carbon. It contains a lot of impurities, like sulfur, nitrogen, etc. Oxides generated at high temperatures are toxic, so even though they are white, they are also toxic.
Hydroelectric power does not require a chimney.
Of course there is smoke in the chimney, and the white smoke is because the smoke has passed through: denitrification (nitrogen oxides), electrostatic precipitator, desulfurization (sulfur dioxide ), and after decarbonization, the heat-containing combustion gases (the white contains water vapor, and when the flue gas with temperature is cooled, white mist will precipitate), and the pollution is very small. If we talk about those with particularly large diameters in the power plant, these are circulating water towers (also called cooling towers or cooling water towers). The white water that comes out is water vapor, which is not polluting.