Where's our energy going?
About 80% of the world population has access to electricity. This number will increase, as more area become developed and urbanized. Different countries have different energy needs due to their economy and development and therefore the consumption of energy varies significantly. For example, in Europe and in the US one of the main area of energy consumption is domestic (houses and office spaces), while in Asia the industry is the major area of energy use. However, in all the three continents domestic energy consumption range from 30% to 40% of the total energy use.
Distribution of Energy consumption in Asia, Europe, and USA Data are elaborated from [1], [2] and [3]
The amount of energy used changes significantly from country to country. For example, in the US the typical house consumes 2 fold more energy than the typical house in Japan and 4 times more than an Italian house. However, if we look individually at the domestic consumption for each of these countries, it becomes evident that in all the three cases we can make a difference in the national energy consumption/waste if we try to reduce domestic household energy needs. Taking a look more closely at the domestic consumption, it becomes evident that heating and cooling systems are where energy is mostly used domestically.
Use of electricity in different countriesElectricity (kWh/year) needs of the average electrified household in different countries. Data from 4.
Household electricity distribution in a typical home The data visualized in this figure are representative of a typical urban home (source). Energy needed for Heating and Cooling (space + water) represents 72% of the total consume. Data from 5.
The first step? Make a difference!
We can try to make a difference by reducing the waste of domestic energy. In an ideal world we should reach a situation where the heating and cooling energy gets close to zero, and the only energy needs of a house will become the one for lighting, computers and small appliances.
We can all make a difference by adopting responsible habits to reduce the waste of energy in our house. Every action can have an impact:
- Substitute old appliances with high efficiency ones
- Decrease the dispersion of heat/cool, by substituting old windows, isolating roofs, and not leaving windows open excessively when operating these systems.
- Replace old heating systems with low consume ones
- Installing roof photovoltaic panels
Different approaches , different country needs. Voluntary or mandatory programs?
Different countries have different sensibilities to this problem and had adopted different strategies to reduce domestic energy waste. We tried to take a look at the different laws in Asia, Europe and the US. The information were not always easy accessible. Also, it was not easy to compare the data that we found. However we discovered that in different ways every country is trying to make a difference. The major difference that we observed is the mandatory or voluntary nature of the program/strategy being applied in different countries.
The European Community has developed energy standards for both new and old houses. It has been estimated that new buildings consume 3 to 5 liters of heating oil per square meter per year, while older buildings consume about 25 liters and sometime reach up to 60 liters. Currently, about 35% of the EU's buildings are over 50 years old [6].
The 2010 Energy Performance of Buildings Directive and the 2012 Energy Efficiency Directive are the EU's main legislation on this topic [6]. Under this directive:
- Each house must have an energy performance certificate based on the energy consumption. This is a one-letter label assigned to the house by a professional (i.e. energetic engineer, or architect) on the basis of the consumption of energy and waste of heating and cooling. Therefore, the type of heating systems, the windows, the isolation of the roof, as well as the territory where the house is located, they all play a role.
- Performance Energy labels must be included in each rental or sale transaction
- All new buildings must be nearly zero energy buildings by the end of 2020 (public buildings by the end of 2018)
- Each country must set minimum energy requirements for new and remodeled buildings
House energetic class standards in Trentino Alto AdigeDifferent parameters are needed to reach a specific class in different countries and regions according to the climate conditions.
To achieve this goal many European countries are financing renovations to help people meeting these goals. For example, in Italy 65% of the expenses for the energetic requalification of your house can be deducted from your taxes (for the fiscal years 2012-2015). France initiated the Grenelle Environnement building plan that consists of an "eco-loan interest-free" dedicated to improve energy and thermal efficiency of buildings. By 2020, this plan should allow investments of EUR 120 billion [7].
The situation abroad: United States
In the US the Department of Energy (DOE)8 has developed a Building Energy Code Program called International Energy Conservation Code (IECC). There are different editions of this code released in 2009, 2012, and 2015. These codes are applied differently to office residential and commercial buildings. For the most part the actions suggested in the codes apply to office buildings and newly built houses. Each state has the faculty to choose to adopt the code. In practice, when building a new house certain standards of energy consumption/waste must adopted by the constructor.
IECC codes in different states Adoption of IECC codes in the 50 American states at the residential level. Figure taken from 8
For example, the states of Ohio and Texas adopted the 2009 IECC (or equivalent), while California updated to the 2012 IECC. This code corresponds to the specific parameters that are to be used when new buildings are constructed (the IECC does not apply on the already existing houses).
Many American states are focusing on the impact that office buildings have, starting by updating all the heating/cooling systems and reducing the energy waste in Federal Buildings. The Obama admistration in 2011 set the goal of reducing energy of commercial buildings by 20% in 2020 [9].
The US does not have a uniformed rating system for buildings based on efficiency or energy consumption. However, there are attempts to create similar programs. For example, The Home Energy Rating system, The Energy Star program, National Green Building Standard and other programs. All these programs are applied locally and on a voluntary basis [10]. Tax incentives, energy efficient mortgages are available in different states. However the lack of harmony between the strategies is a major problem.
In Asia the scenario is more complicated. In many states, the main goal is to bring more electricity to homes, rather than reduce consumption. However, in more urbanized countries, there are attempts to develop a certification system. We had difficulties in drawing a picture of Asia, because of the diversity of strategy in different states. As an example, we looked a China, where the focus has been placed on new buildings, given the fact that there is a very high rate of construction. The Chinese government is promoting a voluntary program similar to Energy Star in the US for the label of house as well as appliances [9].
Household appliacnes: there's a lot out there
In Europe many everyday products such as washing machines, refrigerators and other appliances need to carry energy labels and have been designed to meet minimum energy efficiency standards, identified by a letter code. Some of the European countries are trying to promote the substitution of old appliances with new high efficiency ones. For example, in Italy since the tax year 2012 for every house been refurbished, you can deduct 50% of the cost of the appliances as long as they meet the A+ standard.
In Japan, there is a similar approach being developed, that is not yet mandatory (Energy Saving Labelling program for appliances and lighting) [11].
In the US the Environmental Protection Agency has developed a voluntary program named Energy Star to label kitchen appliances, computers, and materials used to build homes that save more energy than standard models12. This program is now being used also in Europe.
Energy labels of appliances in different countriesIllustration of some labels used in Europe , America and Asia.