Energy certification programs, what rating does my home have?

Did you know that the ventilation system of your home affects the energy rating of buildings? Do you know how energy certification programs work? In this article, we explain how CE3X works, a program developed by CENER and EFINOVATIC, recognized for the energy certification of existing buildings. Next, we will tell you how updating the ventilation system of your home improves its energy rating.

CE3X: an energy certification program

The program's objective is to provide the energy efficiency label that indicates the rating, within a scale that ranges from A (maximum energy efficiency) to G (maximum energy inefficiency).

To obtain the energy rating, the program uses a series of data:

• The materials that make up the building.
• The types of enclosures and their thermal transmittance.
• The type of exterior carpentry (type of glass and frame that make up the openings).
• The thermal bridges that exist in the envelope (responsible for a large amount of energy loss).
• The orientation.
• The shadows cast on the building.
• The geographic and climatic zone.
• The usable living area.
• The ventilation.
• The type of roof.
• The total daily consumption of domestic hot water (DHW).
• The solar protection elements available.
• The different installation equipment: DHW equipment, heating-only equipment, cooling-only equipment, heating and cooling equipment, mixed heating and DHW equipment, mixed heating, cooling and DHW equipment, and all renewable energy sources that enable the reduction of energy demand.

For Large Tertiary Buildings (GT), you must enter the type of fan (constant flow or multiple speeds) existing in the air-moving equipment implemented in the building.

Energy rating

The energy rating provided by the program will indicate the following information (it should be noted that the final energy rating provided by the program will be more accurate as the data entered is more detailed and precise):

• Rating scale (from A to G) and the emissions of kg CO2/m² corresponding to each of the letters.
• The rating of the building.
• The heating demand, expressed in kWh/m².
• The cooling demand, expressed in kWh/m².
• The emissions generated by heating, cooling, and domestic hot water production equipment (DHW), expressed in kg CO2/m² and the efficiency of these installations.

How can I improve the energy rating of my home?

The program provides a set of improvement measures and allows the introduction of measures proposed by the user:

• Reduction of heating and cooling demand by using more efficient systems and improving the thermal envelope of the building to minimize losses (increasing the thickness of thermal insulation, eliminating thermal bridges, and installing high-performance airtight carpentry).

• Improve the airtightness of the building to prevent unwanted air infiltration.

The installation of a controlled mechanical ventilation system allows for improving the energy rating of the building since it enables air renewal without the need to open the envelope openings. Being a completely airtight and closed system, it ensures that there is no unwanted air infiltration through which a significant amount of internal energy is lost.

Increase efficiency to enhance savings

The program CE3X also allows for the economic analysis of the building's energy consumption and the energy consumption after implementing the set of improvements. To do this, prices associated with the different fuels must be entered, expressed in €/kWh; the annual increase in energy prices, expressed in %; and the type of interest or opportunity cost, also expressed in %.

The goal is to build a sustainable, efficient, and environmentally friendly real estate park. Achieving an indoor environment in our buildings that provides high thermal comfort is possible without compromising the health of the occupants and without affecting users' pockets.