In the wake of the global energy crisis, the European Union began taking action in 2002 with the Directive on Energy Efficiency in Buildings. One of the best-known directives in this area, as it introduces the concept of energy performance certification for buildings. Energy efficiency class G It is the lowest on this scale, which means it is the least efficient; A, on the other hand, is at the top of the list and represents the highest efficiency.
Energy Rating
Directive 2002/91/EC introduces the concept of energy certification for buildings as an activity that must be performed by a licensed professional specifically for this purpose, in accordance with each member state’s criteria. Subsequent updates to European regulations have introduced mandatory certification and rating requirements for buildings that are constructed, sold, or rented.
To rate a property on this scale, several indicators must be considered that allow for the assessment of good or poor energy performance. These indicators are calculated on an annual basis and based on the property’s usable floor area, and they provide information on the amount of energy required to meet, under specific climatic conditions, the conditions of comfort considered normal; this includes: heating, cooling, ventilation, domestic hot water, and lighting in certain cases.
Consequences of a G energy rating
Since 2013, it has been mandatory to submit the Energy Certification for Buildings, the purchase, sale, or rental of a property. If a property is rated as energy efficiency class G, this means that it consumes a large amount of energy annually just to maintain minimal comfort levels—well above the national average. In terms of a household’s budget, this translates to higher costs for electricity, water, and gas.
According to studies conducted by Certicalia, annually A Category G home can result in a difference of more than about 1,175 euros per year, in heating, cooling, and hot water, compared to the same home classified as Category C. It’s not an amount to be taken lightly, but it’s not the only consequence; an energy-efficient home is one that, thanks to its insulation properties, better withstands the cold of winter and the heat of summer; it has good natural ventilation and allows residents to enjoy the breeze; it does not experience temperature spikes in certain rooms; in short, it improves the quality of life for its residents.
How to Improve a G Category
The way to improve the energy efficiency of a home or building is through renovations that optimize the passive systems, which improve efficiency without consuming any energy whatsoever, and assets, which are the ones that actually consume energy. It is usually necessary to carry out comprehensive renovations that address both types of systems designed to achieve a significant increase in efficiency, however, each case is unique, and the true scope of the intervention will be limited by its cost-benefit ratio.
Improvements to Passive Systems
The first step for this type of improvement is start with the windows, the most significant source of heat loss in a building or home, and they directly affect how easily a space can be heated or cooled using mechanical systems, thereby directly impacting annual energy costs for these purposes.
Another passive improvement method is the installation of or improvement of the insulation material of walls that are in contact with the outside. Although this method yields better results, it is almost never possible to insulate from the outside, so the most common option is to add more insulation on the inside.
Active System Improvements
As for active systems, the main problem has to do with the efficiency of the boilers, depending on their age, they consume a lot of energy to heat water; today, there is a huge difference in the amount of energy consumed by new boilers and the amount of CO2 they emit into the atmosphere, followed by the refrigeration systems, and in large buildings, the air exchange systems. Another type of active improvement is the implementation of energy-generation systems using renewable sources, such as the installation of solar panels solar panels to generate part of the electricity, and thermal systems to help heat domestic water.
For those interested in this field, Structuralia has developed the Master’s Degree in Building Renovation and Energy Efficiency, accredited by the Polytechnic University of Madrid, with the goal of training professionals to carry out engineering, consulting, and project management tasks in buildings in the areas of energy efficiency, energy system efficiency, and the integration of renewable energy sources to achieve more sustainable buildings.
