Energy: 20 tips to save on your bills

The guide, drafted by the ENEA Energy Efficiency Department, contains recommendations to follow and mistakes to be avoided: 10 tips on an efficient use of heating and another 10 on a smart use of energy. But not only that. A few daily energy behaviors are enough to save up to 10% on your bill: for example, turning off the lights and heating when you leave the house, not opening the windows when the heating is on and turning off the PC when you don't use it. Also, the home temperature should not exceed 20 degrees Celsius.

Among the most effective ways to cut consumption (and expenses) are LED bulbs, which consume approximately 85% less energy than traditional ones. Even high-energy efficient appliances are effective in reducing energy bills: the cost difference between having a refrigerator + washing machine + dryer + dishwasher + oven + heat pump with a high or a low energy rating can reach up to 40%.

There are also little things to do such as shielding the windows at night with shutters or curtains to reduce heat loss and turning off standby lights, which can cut up power consumption by 10%.

Among the mistakes you shouldn’t make, there is forgetting to defrost the fridge and freezer: if they accumulate too much ice, consumption will run; likewise, pay attention to the clothes hanging out to dry on the radiator or the sofa in front of the radiator and to the lights on when you leave a room.

Another way to save money is choosing an efficient type of boiler: condensing boilers allow you to save up to 22% of methane gas compared to traditional ones (in a 130 square meter apartment) while the thermostatic valves on the radiators allow to generate savings of about 13% of methane gas.

1. Use energy-saving light bulbs

   LED lights are a fast way to cut your energy bill as, with the same absorbed power, they are 5 times more efficient than conventional incandescent and halogen bulbs. The average LED bulb lifespan is 15,000 hours, much longer than incandescent bulbs (7,500 operating hours) or halogen bulbs (750 hours), this means less maintenance over time.

2. Improve home insulation

   A well-insulated house significantly reduces energy needs.

   External thermal insulation of the building envelope and in particular insulation of the roof, reduces heat dispersions between 40 and 50%.An efficient insulation minimizes thermal energy demand allowing to install a less powerful and therefore cheaper boiler.

   The installation of a thermal insulation system is economically advantageous if part of an extraordinary maintenance plan like roof restructuring or facade renovation, otherwise it requires a considerable initial cost, but with the advantage of not having maintenance costs.

   Cladding insulation can be done both outside and inside. The second option is somewhat less disruptive but implies losing internal floor area and it’s not always feasible.

3. Insulate roof and ceiling

   A well-insulated roof can make  a real difference on the energy bill, reducing upward heat loss. An important investment which offers considerable advantages.

   In any case, ceilings should be insulated with a proper false ceiling, which can save you up to 20% of energy.

4. Use double glazed windows

   Another important step to properly insulate your home, in addition to constructing an external coat, is replacing old windows, which are often a gateway to drafts and thermal bridges.

   The windows must be made using:

   • highly insulating materials like PVC and wood;
   • thermal break materials;
   • double or triple glazing according to climate needs and an air chamber with argon;
   • particular attention to soundproofing and home acoustics.

   In case of installation of roller shutters, it is a good idea to check that the boxes are well insulated to prevent air infiltration that can alter the comfort level of a home.

5. Use less hot water

   Taking a bath uses four times the amount of water than taking a shower.

   In fact, the average bath water usage is 120 -160 liters, while a 5-minute shower uses 75-90 liters and a 3-minute shower 35-50 liters.

   To further reduce consumption, it is important to turn off the water when lathering up or when conditioning your hair or applying masks; further savings can be obtained by installing jet breakers or flow restrictors on faucets and shower heads.

6. Choose high energy rate appliances

   Replacing domestic appliances, which account for 58% of household electricity consumption may significantly lower your energy consumption.

   For example, by replacing a washing machine from 20 years ago with a current one in class A, electricity savings of 35% could be obtained; on the other hand, replacing a refrigerator could reach up to 40%.

7. Use multi-socket power strips

   On average, a tv or other electronic device in stand-by mode, uses from 1 to 4 Watts (depending on the brand and model).

   If we multiply this figure by 24, the amount consumed in a day is between 24 and 96 Wh. This figure is impressive if calculated over the course of a year, amounting to an estimated useless consumption between 8,760 Wh and 35,040 Wh and, if there are also a DVD player, a decoder , a stereo or a computer, the situation turns out to be even worse. The solution to this problem could be to connect multiple electrical devices to a multi-socket power strip with an on/off switch, that enables you to turn them all off when not in use.

8. Don't leave the light on unnecessarily

   At night, do not leave the lights on in rooms that are not occupied and turn off electronic devices not in use.

   During the day, however, it is important to make the most of the sunlight, trying to keep the lights off as much as possible.

   Remote control applications start to appear on the market which enable you to turn on and off home lights using your smartphone.

   For some time there have also been more sophisticated home automation systems for managing lights and  home devices  like roller shutters and curtains.

9. Install a home renewable energy system

   Installing a system that uses renewable energy can produce electrical or thermal energy.

   These systems, if well combined, allow homes to gain energy independence from external sources of electricity and / or other fuels, and can exploit different renewable sources like the sun, wind, water.

   One of the most popular one is the solar photovoltaic system, made of panels composed of silicon modules, which exploit the incidence of solar radiation to produce electricity.

   A solar thermal system uses the sun’s energy according to a principle similar to a photovoltaic system for electricity production, but with the aim  of heating a liquid placed inside special panels, which in turn, thanks to an exchanger, transfers the absorbed heat to the water which can be used for heating or for domestic hot water.

   Another type of system is the mini wind turbine, which can be installed on the roof for electricity production.

   Then there is the geothermal system, which, in combination with a water-water heat pump, uses the heat released from the ground or ground water to heat the water inside the heat pump through an exchanger; this in turn can be used for domestic hot water or heating.

10. Carry out maintenance of the systems

    It is the first rule of safety, savings and attention to the environment. In fact, a system consumes and pollutes less when it is properly set, with clean filters and without limescale deposits.

11. Monitor room temperatures

    Having the warmth of summer at home in the cold season is a waste of energy and heated dry air is harmful to health. The legislation provides for a temperature of up to 20 ° C, but 19 ° C is more than enough to guarantee the necessary comfort. Each additional degree involves significant energy consumption, with a consequent rising energy bill.

12. Pay attention to how many hours your heating is on

    Keeping the heating system switched on night and day is useless,  in an efficient home the heat collected during the switch-on times guarantees enough comfort even when the system is off. The maximum daily switch-on time varies by law according to the 6 climatic areas Italy is divided into: from a maximum of 14 hours in the E area (north and mountain areas) to 8 hours in the B area (coastal areas of Southern Italy).

13. Shade windows during the night.

    Closing the shutters or using heavy curtains reduces heat dispersion.

14. Do not put objects above or in front of the radiators and do not leave the windows open for a long time

    Placing curtains, furniture or screens in front of radiators or using them to dry linen is a waste of energy as it hinders heat difusion. Instead, it is advisable to place a reflective panel between the wall and the radiator, especially if the radiator is embedded in the wall, which reduces its thickness and the degree of insulation the wall provides. Even a simple sheet of aluminum foil helps to reduce dispersion. Furthermore, to air a room it’s enough to let the windows open for a few minutes, leaving them open means an unnecessary heat loss.

15. Do a house check-up

    The assessment of a technician on the efficiency rate of a property, carried out through the energy audit or the energy performance certificate (APE), allows you to determine the most convenient interventions to contain consumption and costs. The intervention is generally affordable and can benefit of the tax breaks and non-refundable incentives of the "Thermal account". The cost of the consultancy is included in the deductible expenses.

16. Equip your system with a temperature control unit

    An automatic temperature control unit is crucial to avoid unnecessary peaks or sudden changes in power. The possibility of hourly, daily and weekly programming guarantees further energy savings. Home automation also helps to save: chronothermostats, presence sensors and electronic controllers enable you to remotely set the temperature of each room and the switch-on time of the heating systems from your smartphone.

17. Install  thermostatic valves

    These devices work by regulating the flow of hot water to the radiators and adjusting the temperatures of the rooms where they are installed

18. Use a smart metering system

    It enables you to independently manage the heating of your apartment and allows the individual user to save and pay only actual consumption. They are installed on each radiator or in the pipes connected to the central heating system and thermostatic valves in each radiator. The law makes their installation mandatory in condominiums and multi-purpose buildings with centralized heating systems.

19. Replace an old boiler with a condensing boiler

    Condensing boilers differ from conventional boilers since they can ensure an higher efficiency rate, reducing consumption and helping you lower your fuel bills significantly.

    In a traditional gas boiler, the water is heated by the heat of combustion: the resulting exhaust gases are usually carried into the flue and released into the atmosphere. In this way, the heat contained in the flue gas is lost.

    A condensing boiler, on the other hand, uses the heat contained in the exhaust gases, which largely consist of water vapor: in fact, condensing the water vapor present in the exhaust fumes allows the recovery of the latent heat of condensation and consequently means greater energy efficiency compared to a traditional boiler.

    In order to obtain energy, the water vapor present in the fumes must however condense: this occurs  at a temperature below 54 ° C. The condensing boiler cools the water vapor present in the fumes through a specially designed heat exchanger. The energy obtained is used to preheat the water in the heating circuit that returns to the boiler: the preheated water can be further heated to reach the desired temperature by passing through the primary heat exchanger as occurs in a traditional boiler.

    It is important to point out that the supply flow temperature of the heating circuit should depend on the temperature of the outdoor air: for example, it may be useless to send water at 70 ° C to the radiators if it is 12 ° C outside. This means that if I send cooler water to the heating circuit (eg 50 ° C), colder water will return to the boiler (ex. 40 ° C) making the most of the operating principle of the condensing boiler. To do this, it’s enough to combine an external temperature probe with the condensing boiler in order to manage the so-called "weather compensation" of the flow temperature to the heating system.

    However, an excellent solution is to combine a condensing boiler with low- temperature heating systems (e.g. radiant floor panels: maximum flow temperature equal to 35 ° C), which have optimal operating temperatures to make the most of the operating principle of condensation of the water vapor present in the fumes.

20. Defrost refrigerators and freezers regularly

    Defrosting a refrigerator improves its energy efficiency. But your refrigerator may also use more energy if it is near an oven or dishwasher. Place your fridge and/or freezer in a proper place.

For more information please contact:

Nicolandrea Calabrese, ENEA – Head Energy Efficiency in Buildings and Urban Development Laboratory ,