Choose the average technology of your electric motor
The motors represent a minimum saving potential of 10% when changing from inefficient IE1 motors to efficient IE3 motors (ZVEI, electric drives division -2008)
Choose the operation time of your boilers
According to the Energy Saver Trust, boilers older than 10 years are likely to be less than 70% efficient. This means that an inefficient boiler will waste more fuel and require more fuel to achieve the same amount of hot water as modern, efficient models.