At first glance, this sounds surprisingly easy, and yet there is a catch called the rebound effect. Direct rebound in this case means that as soon as something has improved its energy efficiency or general performance, it is almost always automatically used more often, which makes the outcome and therefore the energy requirement identical to before, when you were using a version with lower efficiency less often.
Indirect rebound is a little less obvious: Since higher energy efficiency usually comes along with an overall cost reduction (e.g. if your house is better insulated, you will have lower heating costs), you will ultimately have more money at hand to spend on things like a new laptop or a trip to Spain, which again results in a higher overall demand for energy and therefore in increased individual CO2 emissions. Thus, improving energy efficiency alone is not enough.
So we have to work extra hard to really reduce 😫