The Bitcoin mining software takes about 10 minutes on average for those on the network to solve the complex programme and process a block. Is it bad for the environment? As miners use large and efficient systems to mine blocks and validate transactions, this consumes tremendous amounts of electricity.
It's not bad for the environment, it's just how people want you to think that it's bad for the environment, bitcoin mining is just consuming electricity, it's not like they produce their power unless the mines have their own energy generator like windpower or solar energy. The people who says that bitcoin is a waste of energy are the people that don't have any direct stake in bitcoin or was bitter about the price of bitcoin so high that they regret not buying it and now they want to spread negativity on it to make it go down.