According to Eurostat, households represent a 25% of the final energy consumption in Europe, a sector only exceeded by transport, which represents a 33%. Understanding final energy as the energy that reaches the final consumer’s door, in the case of households this energy is mainly provided in the form of electricity and natural gas, and its use means the payment of 50 to 150 euros per month and family by way of energy bills.
Taking into account that polluting energy sources (coal, oil and natural gas) are still the main origin of this final energy, adopting energy saving measures at home is a beneficial action for both the environment and our domestic economy. In the following lines, we tried to select some simple actions that you can start implementing right now to reduce your energy consumption at home, along with some others that may not be as straightforward but that will generate better results.
If you do not want to spend a single euro:
1. Use fans instead of air conditioning. The breeze created by a fan may produce a temperature drop sensation between 3 and 5ºC, consuming a lot less than a conventional cooling device (heat pump). In addition, the breeze produced by the fan improves the ventilation of the house, avoiding the accumulation of carbon dioxide and repelling insects at summer.
2. Limit the temperature of air conditioning systems. Heating and cooling may represent a 50% of the energy consumption at home, especially in northern European countries, where temperature is far below our comfort range. Setting the thermostats of our heating and cooling devices at 20-23ºC during winter and at 23-26ºC during summer is enough to maintain our dwellings under a comfortable temperature for the body. By reducing the energy consumption of these devices, economical savings may ascend to 120 € per year.
3. Wash your clothes with cold water (unless sanitizing is the goal). A study conducted by Procon Ingenieros compared the energy consumption of a washing machine when selecting two different programmes, one with 40ºC water and another with cold water. The results concluded that the cold water program consumed about 4,5 times less electricity than the hot water one.
4. Switch of your appliances when not in use. Microwaves, coffee makers or computers may be equipped with LED clocks that are always running, as well as other stand by modes. Stand by modes may represent a 10% of the electricity consumption at home. Power strip sockets or timers can be used to easily disconnect domestic devices when we are not using them.
5. Use your fridge in a rational way. The fact of being under continuous usage makes fridges use around 20% of the electricity consumed in a house. In order to reduce the electricity consumption of these devices, a proper maintenance is required. Cleaning the formation of frost will increase the efficiency of the fridge, since ice acts as an insulation that avoids the cooling. Behaving in a rational way will also help reduce the consumption of our refrigerators. Some recently cooked (and still hot) meals that you want to save for the rest of the week may be left cooling outside the fridge before placing them inside.
6. When cooking, take advantage of the residual heat. Due to its high power usage, cooking devices end up being an important part of the residential energy consumption, representing around the 10% of the electricity consumption. Even if using natural gas, we can reduce the energy consumption of these devices by switching them off before our meals are completely cooked. Especially in ovens and closed pots, the residual heat trapped inside these food containers will be enough to finish the cooking process.
Better results may be achieved if you consider investing some money:
1. Substitute your old lighting system by LEDs or other energy-efficient light bulbs. Although the LED technology and energy-efficient fluorescents are a more expensive technology than conventional incandescent light bulbs, their lower electricity consumption and higher lifetime make them be a more attractive alternative, both economically and environmentally speaking. LED and energy-efficient bulbs consume between 2,5 and 5 times less electricity than incandescent bulbs, as well as lasting more than 10.000 hours (about 10 years), against the 1.000h (1 year) lifespan of incandescent bulbs.
2. Paint walls and ceilings with light colours. Using light colours in walls and ceilings makes the best use of natural lighting, reducing artificial light requirements.
3. Substitute your old domestic appliances by A energy label ones. The energy label is an indicator of how efficient an appliance is compared to those with similar characteristics. For instance, an appliance with an energy label A means that this device consumes the 55% of the energy that an average appliance consumes. A B, from 55% to 75%; a C, from 75% to 90%; a D, from 95% to 100% (that is, like an average appliance); an E, from 100% to 110% (that is, more than the average appliance); an F, from 110% to 125%; and finally a G, more than the 125%.
4. Replace your old windows. Old windows (+20 years) use to have a single panel of glass and a metallic framework, which does not really insulate from the outside temperature. The improvement in materials selection and the use of double or even triple layers of glass makes new-manufactured windowsbe up to five times more insulating than traditional single panel ones. This increase in insulation may translate into a remarkable reduction in heating and cooling necessities, saving an important amount of energy.
5. Substitute electric heaters or heating stoves by heat pumps (which can also provide cooling). Heat pumps are nowadays the most efficient devices in terms of heating and cooling, being able to transform 1 unit of electricity into 3 to 4 units of heat/cool, that is, with efficiencies ranging within the 300% and the 400%. The fact of using heat pumps at the expense of electric heaters or stoves will not only save energy but also increase comfort and reduce the risks associated with combustion.
6. Monitor your energy consumption. A last step you can take to become the king/queen of domestic energy saving is to monitor the energy consumption you have at home in order to identify those appliances or processes which consume the most. In order to do so, several manufacturers offer smart sockets, easily controllable by means of an APP, where appliances can be plugged in and their consumption checked. Once identified, you will make sure that the energy-saving measures applied to the most-consuming devices will be the ones making the highest impact in your final energy consumption.
This is the end of our third Weekly Post. We would like to thank you for reading us and encourage you to suggest more energy efficiency measures that are not mentioned in this post, as well as sharing the results you may obtain by applying them. Our next post will talk about the meat industry and its consequences to the environment. Stay tuned!
Author: Eloi Delgado Ferrer
Specialization: Residential Solar PV and Energy Auditing.