Home » Blog » DEC » Display Energy Certificates: a closer inspection
The purpose of a DEC (Display Energy Certificate) is to exhibit the energy performance and the efficiency of a building to members of the public and building users. This is illustrated in a simple graph format on a scale of A-G.
If you’re new to energy management, looking after a public building, or have never had to deal with a DEC before, you may find this useful. Here is a handy breakdown of a DEC and what each component means.
Click on the elements of the DEC to discover more.
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DECs are a legal requirement for all buildings accessed by the public that receive funding from the public sector with a floor area of above 250 m2. DECs and accompanying Recommendation Reports can motivate building occupiers to make energy efficiency improvements, realise energy savings and improve future Operational Ratings.
For further advice on DECs, to get a certificate done for your organisation, or to renew an expired DEC, contact us today.
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This provides information about the owner or occupier of the building followed by the address the certificate relates to.
Each DEC carries a unique certificate number. This is used to search on the Non-Domestic register to verify the validity of the DEC and access the electronic copy of the certificate, see www.ndepcregister.com.
Also displayed here is when the DEC is valid until and the total useful internal floor area (which also determines how long the DEC is valid for: larger buildings need to have a DEC renewed more frequently).
To add context to the current Operational Rating, ratings for the current year and past two years, along with the start date, is displayed here.
This is the building’s Operational Rating in relation to average energy performance for the current year. The numbers shown represent comparative energy efficiency and 100 represents a benchmark for average energy performance for a building of this type. If the number is above the line, your building is performing better than average.
At the very bottom of the DEC is a table that shows building usage against typical energy use for kWh per sqm per year and the percentage of renewable energy (as displayed in the chart relating to Total CO2 emissions).
The building’s energy use is converted into CO2 and is broken down into different types of fuel: electricity, heating (usually gas and / or oil) and renewables (such as biomass boilers, CHP, Solar Panels etc). This section displays the total CO2 emissions for the current year and previous two years.
In this section you will find information about how the DEC was prepared. This includes which energy assessment method was used and the date of issue of the certificate. It also identifies the Assessor who produced the certificate with details of their accreditation scheme and membership number.