Cooperation / Energy at home

Energy at home


When we talk about `energy at home or domestic' we mean the one that is used in the houses, that is the amount of the energy used for heating and the electrical consumption. The residential and commercial sectors cover 30% of the national consumptions in many countries, and are responsible of the emission of approximately 18% of CO2.


In a house, the energy is used for multiple activities: the energy is transformed from many devices in order to satisfy all our requirements. The devices are nothing other than the household-electric ones, the boiler for the winter heating and for the sanitary water, the light bulbs etc...

Every time we use energy transforming it, eg., from electrical current to light, from gas to heat, in this transformation an energy part is lost without any possibility of recover it. It is of a physical phenomenon impossible to avoid, it is like a sort of tax that we must pay to the nature. Within certain limits, improving the technology of devices, we can however reduce this tax and to have greater benefits, that is to increase the performance. The improvement of the performance in practice means to deal with the efficiency concept, it is worth to say the relationship between the energy effectively used and the demanded energy value. One of the causes of the enormous energetic consumption is for sure due to the use of inefficient technologies in the production, distribution and final use of the energy.

Another fundamental aspect is instead the energy saving, therefore the attention degree that everyone has in using energy and resources; as an example to leave the tap open while using soap involves one useless gas and water waste; in this case a simple gesture of the hand reduces the consumptions without compromise the well-being.


In order to use a likeable metaphor, our house can be represented by a holey bucket in which we have to assure a certain water level wanted to be maintained. To such aim it is possible to follow two roads:

  1. to open the tap and to continue to fill up the bucket in order to compensate the losses of water from the holes;
  2. first of all to act on the bucket, closing all the holes and then to open the tap in order to compensate the reduced loss of water.

Obviously the second one is the correct approach, while the first one feeds waste and useless energy consumption.


In our houses, the water is all the energy that we use (thermal, electric, mechanic etc…), the holes are instead all the energetic dispersions that happen through the covering (walls, roof, windows), or caused by the use of badly efficient electric systems and, or in advance because of a wasteful behavior!

To close the holes of our bucket means therefore to save energy giving more attention to our daily gestures, and improving the technological efficiency of the house in all its parts, from the appliances, to the walls, the heating system.... Energy saving and energy efficiency are the key in order to reduce our impact on the atmosphere and in order to reduce in a consistent way the weight of the bills!

To become conscious of how much is consumed can be a first important step in order to change our habits; the following tables report some useful data as references in terms of resources and expenses

Electric consumption and monthly average cost of some appliances

kWh                Euros perl month (*)


Refrigerator               always tuned on                    60                              11.00

hair dryer                    3 hours a week                     13                                2.30

1 hour a week                         4                                0.70

½ hour a week                           2                             0.40

washer                        5 washing a week                    28                             5.00

3 washing a week                                17                             3.00

2 washing a week                    11                             2.00

Hot water boiler          always turned on                    300                             54.00

6 hour a day                           146                             26.30

TV                              10 hour a day                            60                             11.00

6 hour a day                             36                             6.50

3 hour a day                             18                             3.20

1hour a day                                6                             1.10

dish washer                14 washing a week                22.4                             4.00

7 washing a week                  11.2                            2.00

3 washing a week                    4.8                            0.90


(*) average cost kWh: € 0.18


Energetic consumption (liters of oil and water) to produce hot water that one person uses during the year

liters of oil                        liters of water


shower                                                           320                            25,000

wc                                                                   620                            50,000

tap                                                                  240                             44,000

tap  with flux-reducer                                     150                             23,400

traditional washer                                            55                                4,700

low consumption washer                                 40                               2,600

traditional dish washer                                    250                              7,300

energy saving dish washer                             160                              3,650




Yearly CO2  emissions

Medium size building, well insulated

2500 kg CO2  per flat

Same building not insulated

4200 kg

6 hours on water heater

1000 kg

Always on water heater

2100 kg

Heating system 18°C

2900 kg

Heating system 22°C

3600 kg

 A CLF bulb

210 kg

Standard bulb

360 kg

Energy saving washing machine at 30°:

250 kg

Standard washing machine at 90°C

360 kg


Tips to save energy


As we have already said previously, there are virtuous behaviors that carry to a sensitive reduction of the consumptions, making a better use of the energy. Therefore we can improve the efficiency without to acquire a new boiler or a more efficient washing machine but only making attention to small things.

In order to start it is very good to record every week or every month on a notebook your gas, electricity and water consumptions. To become conscious of the consumptions helps to modify the lifestyle.


For every electric device

  • Switch it off when not in use
  • Switch off also the standby system when is not in use for more than 1 hour



Temperature during cold season

- During the day, you should maintain the house’s temperature at 20°C.

- Please, remember to held the thermostat low, you should reduce heating cost about 7%

- During the night, put the thermostat on 16°C




- Put at least 10 cm between refrigerator and the wall 

- Regulate the thermostat on medium temperature

- Don’t put hot foods into refrigerator or freezer

- Close quickly the refrigerator’s door


Washing machine

Choose washing cycle at low temperature

Don’t use too washing powder 

Use decalcified washing powder

If you can, let clothes dry at sun 

 Dish washer

-Choose the washing cycle adapted to dishes

-Choose cold, rapid and low cost washing cycle

-Don’t dry the dishes with hot air

-Don’t use too washing powder 

 Electric stove

-Don’t open frequently the electric stove’s door and stop the stove five minutes before the end of cooking

 Summer cooling

  • Remember that light colors reflect heat and dark colors absorb it.
  • Close draperies or shades during the day to block the sun especially on windows that face south or west.
  • Open them in the evening to let cool air in.
  • Turn off lights when not in use.
  • Cook on the grill to keep cooking heat outside.

When using the stove, vent cooking heat outside with a range hood

 Lighting system

 Ø  In phase of furnishing, estimate the disposition and the amount of light sources in relation to the use of the rooms. In order to correctly illuminate a room, in fact, it is not necessary to increase the power of the light bulbs, and therefore the consumptions, but to choose the kind of lamp and the best positioning

Ø  Always choose the natural lighting system when possible, it is better and free.

Ø  Remember to switch off the lights when the room is not used.

Ø  In the morning open the curtains ones rather than to switch on the light.

Ø  Clean periodically the light bulbs from the dirt.


TV, computer and other battery appliances

 Ø  The television is one of the household-electric appliances that consumes more, above all because it remains ignited for many hours of the day; a good book or music can be a valid alternative.

Ø  Correctly set up the option "energy saving" on the PC.

Ø  Switch off the monitor for pauses that exceed the 15 minute of span

Ø  Switch off the computer when it is not in use for at least an hour, the idea that frequent switching on and off of the system can damage the machine is false.

Ø  Remember to detach the plug of the battery charge systems of mobile or other apparatuses when the charging ends, in fact even if the batteries are not connected, the transformer continues to work uselessly wasting energy.

Heating system

 Ø  Set the time of heating

Ø  Don’t turn often on and off the heating system

Ø  Regulate thermostat on a lower temperature: a good one could be 17-18°C where can be reached a good comfort; during night a temperature of 16°C are sufficient. Every degree in advance makes to increase the bill of 6-7%

Ø  Keep closed the radiators of the rooms that are not used, closing the doors to avoid dispersions.

Ø  Don’t keep open too much the windows in the cold days: if it is too much warm, adapt the thermostat temperature rather than to open the windows.

Ø  In order to change air, it is better to open the windows for 5-10 minutes, rather than to hold the windows partially closed for a longer time, possibly make this operation in the warmer hours of the day.

Ø  Periodically vent the radiators

Ø  Do not cover the radiators.

Low cost actions to save energy

 If we already have a virtuous behaviour and we lend attention to reduce wastes, then the successive step is to try to improve the efficiency of our house making actions on structure, systems, and apparatuses. Structural interventions usually demand huge sums to be invested as will be explained in the following; however it is possible to adopt simple technical devices and sagacity to contain costs. These low cost actions, moreover, are easily repaid and in a reasonable amount of time with the achieved saving.

 Electric devices interventions


Ø  During the purchase it is better to choose models with high efficiency (class A or better): they cost more, but the saving is remarkable.

Ø  For the washing machines, it is better to acquire the ones that employ little water, therefore also little energy for its heating, and little washing powder. Moreover if the washing machine is predisposed with the warm water inlet system it is possible to furnish warm water heated with a more efficient way instead of the electric internal device. The models with wash and dry are comfortable but energy consuming. Analogous comments are worth for the dish washer.

Ø  For the ovens, the self-ventilation function is advisable because it favours an uniform distribution of the heat.

Ø  In the case of refrigerators, carefully estimate the ability in relation with the requirements of the family: 100-150 liters are good one person, 220-280 liters for 2 persons, 300 liters and beyond for more than 4 persons.

Ø  For the air conditioners, if there are no particular requirements (es. presence of old persons or children in family) it is better to avoid the installation; in any case it is important to acquire the higher efficiency models; it is possible to use, in alternative, fans.

Ø  Avoid to install electrical water heaters, and however use them when strictly necessary; electrical water heaters have consumptions really high.

Ø  Avoid the electric appliances stupid or easily replaceable with similar devices (es. better the moka than the machine for the coffee).


Ø  In the rooms of the house few used or in the garden, position sensors can be installed that only set in action the bulbs when it is revealed the presence of someone.


Other tools

Ø  In the zones of the house where there are numerous electric small devices it is good to install a multiple plug with a switch: these system permits with a single gesture, to switch off everything during the night or when nobody is in house.

Ø  The rechargeable batteries are more convenient than the single use ones.

Ø  Among the single use batteries it is better to prefer thee alkaline ones that guarantee better performances.

 Heating system interventions

Ø  In case of good conditions of the external walls, it is possible to increase the insulation from the inside using easily found materials and with a simple DIY application.

Ø  Insulate the cavity walls: when the wall has a cavity, it is possible to fill it with insulating material (es. the expanded clay). It is a convenient and economic way to reduce thermal consumptions.

Ø  In case of central heating system, install a system of heating count for every user.