Annex 39 High Performance Thermal Insulation Systems (HiPTI)
A significant part of end energy used in western countries is for heating and hot water production. The amount of energy required depends largely on the thermal insulation, and efficient thermal insulation is a key issue for reducing CO2 emissions.
There are two ways of obtaining improved thermal insulation:
- Increasing the thickness of the insulation, a method which has been used for the last 20 years but which has various disadvantages, for example the cost of construction, the loss of space, less available space for renting
- Improving the thermal insulation properties by reducing the thermal conductivity of the insulation material
The second approach could enable new construction details and easier application in building retrofit and energy efficient appliances, if the insulation thickness could effectively be reduced.
The general objective of the project was to develop reliable components for buildings based on HiPTI. Called 'HiPTI systems' (e.g. fašade elements, doors, water heaters etc), the successful developments should lead to competitive products which are available on the market. The technologies used in the Annex are Vacuum Insulation Panels (VIP), which consist of a nanoporous core material, packed in a gas tight envelope which is evacuated to a pressure of less than 1 mbar.
In conventional types of thermal insulation, the gaseous heat transfer rate is dominant. To reduce it, energy transfer between gaseous molecules must be reduced. This can be achieved by reducing pore size, reducing pressure or by replacing the air by heavy gasses (Argon, Krypton or Xenon for example).
Heat transfer in air can be reduced to zero in micro-porous silica when pressure is below 50 mbar. As a side effect, radiation is also reduced to almost zero.
Research into high performance insulation systems is important for the following reasons:
- Increasing legal insulation standards for new buildings,
- The high cost of thick insulation, especially in relation to available net room space, the expense of construction, etc),
- The increasing popularity of 'Low Energy Building Concepts', with even lower U-values,
- Limitations of space for retrofit insulation in existing buildings,
- Thermal insulation is one of the most important measures to reduce CO2 emissions
HiPTI is needed:
- In the long term(25 years+): Everywhere
- In the short and medium term (10 years+): Where space is costly (In order to gain more net available room space, and to avoid thick expensive wall constructions in low energy buildings)
- Where very little space is available (retrofit for floor heating systems, doors, flat roofs, interior wall insulation, window enlargement, water heater and ducts.)
The project was divided into three research areas:
- Basic concepts and materials
- Application and system development
- Demonstration and information dissemination
Thermal insulation and VIP with identical thermal quality.
Participants: Canada, France, Germany, Netherlands, Sweden, Switzerland
In addition to the following publications available for download here, related research and conference papers are also available at the Annex 39 website
|Vacuum Insulation Panels
Study on VIP Components and Panels for Service Life Prediction of VIP in Building Applications
Hans Simmler, Samuel Brunner, et al
Vacuum Insulation in the Building Sector: Systems and Applications
By Armin Binz, Andre Moosmann, et al
Vacuum Insulation: Panel Properties and Building Applications - Summary
Edited by Markus Erb
High Performance Thermal Insulation Systems - Vacuum Insulated
Proceedings of the International Conference and Workshop
EMPA Duebendorf, January 22-24, 2001
Edited by Mark Zimmermann, Hans Bertschinger
Switzerland, EMPA, 2001, 128 pp.