You want to build a widget in a factory. The factory consumes 1 MW of power to operate and emits 5 kg per hour of pollutants into the air as a byproduct of widget production.
If the work the factory does is outsourced to China, the widgets don't necessarily cost less energy or emissions to produce. So you've just shifted emissions from one country to another — it's an accounting trick, not a genuine reduction.
If the work the factory does is outsourced to China, the widgets don't necessarily cost less energy or emissions to produce. So you've just shifted emissions from one country to another — it's an accounting trick, not a genuine reduction.