Energy efficiency

Savings and Safety through Energy Efficiency


How to reduce your electricity bill by 10 - 15% and save your money, without scrimping on comfort and everyday needs and habits even for a moment? You can make it if you behave in an energy efficient manner, and it's actually very easy.


Energy efficiency refers to technical devices and certain measures and behaviour, when the aim is to minimize the energy consumption without compromising the comfort level nor the business efficiency. The increased efficiency results in significant money savings, but a direct influence to the environment protection is not negligible at all.     


Manner in which electricity is generated has a great impact on climate and environment. If you behave in an energy efficient manner, the quantities of electricity savings are as if an additional thermal power plant existed. Nowadays, energy efficient behaviour is the model behaviour in the most developed countries of the world and it also becomes a cultural reflection. Electricity consumption in Serbia is 2.5 times higher compared to world average per domestic product unit and we have to reduce it by nine percent by 2018 in order to conserve our natural resources for future generations.


What should we do? Only small changes in behaviour when handling household appliances are needed. We should adhere to small tips to be reminded through a series of texts in the forthcoming period.


You may be wondering what energy efficiency has to do with Electric Power Industry of Serbia? First of all, it's our obligation to provide stable and reliable supply of all customers. It is predominantly conditioned upon a secure complex technical and technological system, as well as resources. Rational electricity consumption of all of us together represents one of the most important preconditions for establishment and maintenance of a secure and reliable system, since energy efficiency leads directly toward the increase in the quality of life, industry competitiveness and energy safety.    



Houshold Energy Efficiency Test


Every owner of apartment or house may easily test energy efficiency of his own home. He should just go through all the rooms, apply appropriate changes and thus make his home energy efficient.

If you use incandescent light bulbs, replace them by the energy saving light bulbs – whether CFL or LED light bulbs. Turn of the lights when leaving the room and find the most efficient place for lightening. Walls painted in bright colours will reflect more light and there will be no need for additional lightening.

Check if the water pipes are isolated and, if not, isolate them and you will be on the right track.

Due to inappropriately isolated doors and windows and due to the places in the walls where outdoor units of the air conditioning are mounted, significant losses of heating or cooling energy, depending on the season, are recorded. Therefore, all holes and gaps should be well closed by band or other materials, such as putty. 




Did you know that by energy efficient use of lights we may achieve important savings in electricity consumption and thus reduce the electricity bill?


Six 25 W incandescent light bulbs produce together the same quantity of light like one 100 W light bulb. Additionally, such “bunch" of light bulbs spends more energy by even 50%. Hence, use one light bulb of higher capacity instead of more than one light bulb of lower capacity.


The simplest way to be energy efficient is to use to the maximum daily light. Clean your windows regularly, avoid placing too large number of plants in front of the windows, as well as dark curtains, and place tables in the work areas in such manner so that they are exposed to the sunlight as much as possible.


Energy saving light bulbs spend five to six times less electricity for the same quantity of lightening and have up to ten times longer lifetime compared to incandescent light bulbs. Lifetime of incandescent light bulbs and energy saving light bulbs is usually 1,000 and more than 10,000 hours, respectively.


Likewise, incandescent light bulbs transforms only 5% of input energy into light while the rest of input energy transforms into the heat. That's why the lights should be turned off in the rooms where you rarely stay.


It is the best to choose the A class light bulb. B class light bulb spreads poor light, but it does not spend much more electricity compared to the A class light bulb, so that it may be bought if the price is favourable.


Selection of light bulb capacity depends on where it should be placed. The table below shows incandescent light bulbs and “energy saving light bulbs" frame ratio as benchmark for customers.



incandescent light bulbenergy saving light bulb
40W9 – 13W
60W13 – 15W
75W18 – 25W
100W23 -30W
150W30 – 52W

Colour of light is professionally called temperature of light. In general, there are two colours of light that energy saving light bulbs may produce – white and yellow light, i.e. worm/soft white light and day white light. Soft/worm white light is recommended for rooms where people spend most of the time. For instance, some people use white light for reading, as it makes better contrast between black letters and white paper. Otherwise, colour of light is expressed in Kelvin (К). The lower the number, the “warmer" the light. The packaging should contain this information, as well.


Although the form of the light bulb might sound trivial, it must be taken into consideration for which place the energy saving bulb is being bought, since there are so many forms of light bulbs, from stick to spiral. They differ mainly in length, i.e. height. Lighting spots closed by balls (in the storage room, for example) require shorter light bulbs, therefore it is the best to take spiral “energy saving light bulb". 


Refrigerator and Freezer


Refrigerators are the second major consumers in the kitchen.


First of all, choose refrigerator fitting your family needs. Be aware of the fact that the refrigerator of medium capacity spends 300 kWh annually, regardless of whether it is full or empty, while monthly consumption rises 10-20kWh for each 100 litres of additional capacity. Recommended capacity of refrigerator looks like this: for one person – from 100 to 150 l, for 2-4 persons – from 220 to 280 l, for more than 5 persons – up to 300 l. By buying the refrigerator exceeding your needs, you waste energy unnecessarily.


Find the coolest spot in the house to place refrigerators and freezers (not near the stove, radiator or boiler). Cooler space means higher energy savings, taking into account that each degree down may lower the electricity consumption even up to 6%. Avoid to expose refrigerator and freezer to sun rays, as well. When you place refrigerator and freezer, be sure to leave a sufficient space for ventilation between back of the appliance and wall (around 10 cm) to prevent overheating and thus increase in electricity consumption as well.


At times, clean (but carefully, not to damage the pipes) the dust from the back of refrigerator where the heat is discharged.


Before you open the refrigerator, think about what you need and do not keep the doors open longer than necessary.


Set thermostat to medium position. Lower temperature does not mean necessarily better food storing and energy consumption may increase even by 10-15%. Do not put hot or warm dishes in refrigerators or freezers. Before you freeze the food, cool it at room temperature, then in the refrigerator and finally put it in the freezer.


Frozen food should be first defrosted in refrigerator, because that way it cools other food in refrigerator “for free". Refrigerators and freezers should be timely defrosted (when ice thickness reaches 3 to 5mm) for the purpose of energy saving and extension of the lifetime of appliance. Standard freezing temperature is 18 degrees Celsius, and if you set lower temperature only by 1 degree, you may increase the electricity consumption by 5%.






We've all been in the situation when, at the same time, more than one burner is on because we wish to be the best possible chef and to prepare nothing less than perfection for loved one or family. Then main dish, appetizer and dessert should be prepared all at once, not to mention the soup and roast… In this case, as in many other occasions, there is a lacking awareness of energy efficiency and money savings that may be achieved by changing only a few habits, which is very important particularly in winter period due to higher consumption and electricity bills.


Always cook with the lid on the pot. Thus the heat is kept longer in the pot and the condensation of steam in the kitchen is less. Cooking with the lid on, a saving of up to 20% of electricity may be realized.


Adjust the size of the pots for cooking to the quantity of food that you prepare. Preparation of small quantity of food in a large pot means loss of energy. Additionally, when preparing tea or coffee, only the quantity of water needed should be heated. The pot in which the water is heated should be covered with lid, as well, enabling quick boiling.


Check whether the bottom of the pot is smooth and level. The food will be cooked faster in a pot that adheres better on the hotplate of the cook.


Use the minimum heat you need when cooking. Once the water has boiled, reduce the heat to minimum to keep it boiling. Higher temperature will not enhance faster food preparation, but the evaporation of water.


Turn off the burner a few minutes before you think the meal is cooked, as it will keep high temperature and the food will keep on cooking. Glass ceramic hob sends heating energy to the very bottom of the pot very precisely, and thus it is more effective than classic hobs.


As for gas stoves, avoid too big flame licking around the pot. It is dangerous and also means additional waste of energy.


Very efficient when baking are ovens with fans which may economise from 10 to 15% of energy. Only some meals require preheating of the oven to a temperature wanted. Remember that each 10 minutes of oven preheating wastes 0.06 кWh, which may contribute to rise of annual electricity bills if applied regularly. Oven doors should be open as short as possible since 20 % percent of heat is being wasted on that occasion, and you may also turn it off 10 minutes before the end of cooking as it keeps the heat longer. And, finally, clean regularly your oven to have an extra saving of both electricity and money.



Small home appliances


The direction in which microwave heats the food is from the outside toward the centre, so if you cook diverse foods, you should put smaller pieces in the centre of the oven and the bigger ones around them.


A heater that is covered with the limescale requires long time and more energy to heat the water compared to the clean one, that's why you should regularly remove the limescale from it. You can do it simply by using apple cider. Always heat only as much water as needed for coffee, tea or anything else.


Always turn of the computer when you don't use it. If you have to leave the computer on even when you don't work, turn off the monitor at least, since it consumes more than a half of energy of the entire system. Despite common opinion, turning off and on the computer does not require additional energy consumption, nor is it a burden for the computer, but extends the lifetime of its components and enables savings. If you let the monitor on overnight, you will spend the quantity of energy which could be used to heat 6 dinners in a microwave.


Be aware that the “stand-by" option, particularly TV or DVD “stand-by option, consumes even up to 6% of electricity in the household. Specifically, TV in “stand-by" mode of operation consumes even up to 24% of energy compared to the time when it is on.


Cell phone, laptop and digital camera chargers waste energy even when the devices are fully charged and also when they are connected to the slot without the device connected on the other side. It is proved by the fact that the chargers connected to the slot but not charging are still warmed up.


Likewise, electrical devices in “stand-by" mode may achieve up to 10% of total electricity consumption annually.


As these devices are generally placed close to each other, they can be connected to one divider, i.e. extender, enabling thus their turning off by pressing only once the button when leaving the house or before going to sleep.




There is no need to cool the room under the 21 degree Celsius. It is not good for your health and it generates unnecessary costs.


Difference between outdoor and indoor temperature of the room where you are staying should not be more than 10 degrees Celsius.


Install air conditioning out of a direct reach of sunlight.


Regularly maintain purifying filters as well as outside unit of cooling device.


Reduce necessary quantity of cooling energy by good isolation of the walls and windows.

Energy Classes and Electricity Consumption

If you choose appliances with the label of “energy star", when buying the new ones, it's clever choice, since such appliances belong to the group of appliances with the lowest electricity consumption. 

In technical goods shops, almost all household appliances and electric devices have labels with energy class indications and average electricity consumption of these devices. Energy class range is expressed by the letters: “A" – “B" – “C" – “D" – “E" – “F" – “G"…

Appliances and devices with the highest energy efficiency, with the lowest electricity average consumption are the appliances and devices labelled with: “ААА", “АА", “А" and “B". When you buy devices such as TV or monitor, it is important to pay attention to the consumption in “stand-by" mode. Modern devices have visibly indicated consumption.