Experiments to test DuPont™ Energain® in a real life environment have been conducted by DuPont and the EDF Group (Electricité de France) at a test site in France. One of the objectives was to prove the benefits of DuPont™ Energain® when installed in a light weight structure.

The decision was taken to use the most critical part of the structure, the attic, in order to verify performance in "a worst case scenario" of conditions. The attic is generally the portion of a building which suffers most from overheating and so DuPont™ Energain® panels were installed behind the plasterboards, in the walls and in the ceiling of one of the test rooms.

A second room with an identical volume and structural setup, fitted with identical multiple temperature sensors was used as the reference room. The only difference in between the two test spaces was that the second room was not fitted with DuPont™ Energain®. A third space, located in between the two test cells, was used as a thermal buffer zone.

Test period

From August 2006 to April 2007: data collected over 3 seasons (summer, mid-season & winter)

Ventilation Strategy

• Summer: 0.5 vol/h (day) & 2.4 vol/h (night)
• Winter: 0.5 vol/h (day & night)

Test Results

Summer

Testing mode

• Free evolution of the temperature inside the two testing spaces

For the summer season, significant results were obtained despite the fact that the solar radiation factor during the month of August 2006 was only medium.

• The maximum peak temperature difference obtained in the period of August 15, 2006 to September 24, 2006 was 6.7°C. In average over this period, the peak temperature was decreased by 4.5°C due to the installation of DuPont Energain.
• The calculated energy savings per day, for a temperature difference of 6.7°C in kWh and for the test room (68 m³), is close to 8.2 kWh/d.
• If a maximum of 25°C had been defined as the criterion for comfort, using DuPont Energain would have allowed to come very close to this requirement.

Pervious to the test, DuPont had simulated the experiment with the help of CoDyBa (CDB_dDDN_V2), a proprietary simulation software, which had given the same order of magnitude and predicted that these results were to be expected.

Mid-season / winter

Testing mode:

• Installation of a heating system, set-point at 20°C, in the two test spaces
• Measurement of the temperature differences during the day and the consumption of the heating system in both spaces.

For the mid-season and winter, the results were equally significant

• The maximum peak temperature difference obtained in the period of March 4, 2007 – March 17, 2007 was 5.4°C
• On days where solar radiation was present, DuPont Energain not only allowed for significantly cooler rooms but equally for using these solar gains to reduce the energy consumption of the heating system. Over this period, the heating consumption was decreased by 7.8% with a potential to go up to 30% depending on the weather conditions and the structure of the building.

The close-up of one day in this mid-season/winter period explains how the energy savings of the heating system works:

• During a day with solar radiation, DuPont Energain captures the “excess” heat, a temperature difference of 5.4°C is obtained
• During the cooling down phase, the temperatures in both test spaces come close up to the point where DuPont Energain is keeping one test space warmer.
• This time is equivalent to 2-3 hours, during which the heating system does not switch on in the space where DuPont Energain is installed – this can mean significant energy savings during days with high solar radiation – a measured 7.8% for the test period mid-season/winter with a potential to go higher for higher solar radiation