# Energy Efficiency Index (EEI) what is it, for washing machines, explained, calculation

In EU washing machines assigned to energy efficiency class of A ++ to D.

As the definition of class is taken Energy Efficiency Index (EEI), performing the calculation of the index of energy consumption on the real energy of the washing machine, the washing machine is installed class energy efficiency.

The index of energy efficiency is the ratio of real consumption of resources calculated and multiplied by 100.

**Energy efficiency index formula**

EEI is the percentage of actual energy consumption by calculation, if the washing machine consumes 46% less energy from the index calculation, it is assigned an index A+++.

Energy Efficiency Index |
The energy efficiency index of washing machine |

A +++ (most effective) |
EEI <46 |

А ++ |
46 ≤ EEI <52 |

А + |
52 ≤ EEI <59 |

A |
59 ≤ EEI <68 |

В |
68 ≤ EEI <77 |

С |
77 ≤ EEI <87 |

D (less effective) |
EEI ≥ 87 |

** The formula for calculating Energy Efficiency Index (EEI)**

**AEc** - Annual energy consumption of household washing machine, is determined by the laboratory during tests in the real conditions.

**SAEc** - Typical power consumption of the washing machine, based on a formula approved by the order of calculation of EU Directives.

In calculating the energy consumption of standard washing machine uses several types of formulas, the basic principle of the following.

- It takes account the power consumption in standby mode, an example of washing clothes is over but not taken out and a washing machine is in standby mode.
- for the calculation is assumed that a washing machine performs 220 washes per year, cotton. Of these 220 washes laundry 94 at full load and wash temperature of 60 ° C, 63 at half load washing and a temperature of 60 ° C, 63 half load washing, washing temperature 40 ° C.
- The time of washing is also calculated

**These formulas give an average data on the energy and error in these calculations is very high and may reach 40%. So much does not make sense to look at the energy efficiency ratio.**

**Factors that may affect the calculation of the ratio:**

*The major part of the power is spent on heating water, the less water the machine will use the sooner it will heat it and spend less energy is automatically a class above, but the quality of the wash in question.**Washing machine with a small volume and loading of clothing around 4 kg. always have a class A ++ and A +++ kind of washing machine is more economical compared to the washing machine at 6kg., but to wash 12kg. Apparel Machinery will hold 3 to 4 kg of washing and 6 kg. only 2 wash.**How much water is used at half load, manufacturers do not indicate, but a washing machine spends 50% of full load another 60% this option is put manufacturers and described in the specifications.*

The most effective way is to calculate how much energy is needed to wash 1 kg of cotton clothing.