The present invention provides environmental equipment which is able to remarkably reduce operating costs and a power generation system comprising same, comprising: a boiler; a power generation unit for generating electricity by steam generated from the boiler; first denitrifying equipment to which exhaust gas is delivered from the boiler and which sprays a reducing agent into the exhaust gas to denitrify the exhaust gas; a low-low temperature electrostatic precipitator for collecting dust of the exhaust gas provided from the first denitrifying equipment; second denitrifying equipment which sprays a reducing agent into the exhaust gas provided from the low-low temperature electrostatic precipitator to secondarily denitrify the exhaust gas and allows the exhaust gas to be provided towards a smokestack.