SOME TECHNICAL QUESTIONS
Why are the ratios measured per square metre and not per user of the building ?
It is not satisfactory to calculate these ratios per user of the building because this value varies in many cases. For example, the number of pupils that attend classes at a school changes each school year. Another example is the changing numbers of staff due to flexible employment patterns.
Are the classification results of buildings comparable ?
Classification results of buildings are only comparable if these buildings are situated in the same climatic zone. The building type is irrelevant for the comparison since the classification scheme is adjusted to the building type. However, most important is to show the improvement of the building itself over the years.
Why does Display® use a local weather correction factor ?
As the final energy consumption of a building depends on climatic conditions and since these climatic conditions vary at one particular geographic location over the years, the consumption data have to be corrected. This correction concerns the energy consumption for space heating. To apply the correction the amount of final energy consumption for space heating is multiplied with the weather correction factor. It is usually provided by energy utilities or meteorological offices.
The weather correction factor does not take into account climatic differences between two different climatic zones. That is why the classification result of a school building situated in Portugal cannot be compared with the classification result of a school building situated in Finland.
Is it possible to import existing data ?
Up to the present, there is no mechanism for importing your existing data into the Display® database. We are currently looking at extending the capabilities of the tool to make it possible to import data to the Display® database so that you can produce a Display® poster quicker.
Which data sources does the Display® calculation tool use ?
Display® mostly uses data based on the GEMIS program, but provided by different sources such as the Institute for Housing and Environment (IWU) Darmstadt, Germany or the database ProBas which is run by the German Umweltbundesamt. In countries that are not part of the EU27 other National sources have been used. Furthermore, data coming from the International Energy Agency (IEA) is applied for the national energy mix. The classification scheme for school buildings leans on the Danish classification scheme for this building type. For detailed information on the data sources used, please have a closer look at the online wiki users’ guide.
Which different kinds of energy supply of a building are included ?
The Display® poster generation tool provides for all the most commonly available energy sources used to supply a building with energy. These are gas (natural and liquefied), fuel oil, district heating, coal, solar thermal collectors, conventional electricity, certified green electricity, and photovoltaic installations on the building. Furthermore, cogeneration units in the building can be taken into account. If you use different energy supplies, it is possible to calculate an individual solution.
Why do you only use one single Classification scheme per building type for the whole of Europe ? Is it not more appropriate to develop a classification scheme per climate zone ?
Firstly, varying the classification from member state to member state would be a significant limitation on the label. Using the common A to G level, of course, it is easier to reach the A level in warmer climates, but at the same time the energy saving potential is lower. This means for example that a lower insulation level is sufficient in Portugal to reach class A, which is well in line with the economical feasibility : as a higher insulation thickness would not be economical if the heating load is low.
Secondly, member states are developing their own implementation scheme for the EBPD, so they will introduce different classification schemes. In this case it is easier to replace the Display® classification on the Display® poster with the national classification scheme (as done in France) than to replace a national classification scheme developed under Display® by the one prepared by the member state itself.
Do you check the data that is entered ?
There is no regular check on the data you enter while using the Display® poster generation tool on the Internet. That is why we advise you to read the users’ guide before collecting the necessary information and before entering this information into the Display® database. Energie-Cités cannot take any responsibility for the data that participants enter into the database.