Status

finished

Summary

Purpose

The main goal of the study in hand is to indicate and identify future influences of the Austrian domestic architecture on the energy-consumption and the CO₂ emissions by using complex analysis and descriptions.

Since the Kyoto-Protocol got into force at February 16^th 2005 Austria and the other attending nations are bound to reduce their CO₂ emissions at an average decrease in average 5% in comparison to 1990 in the upcoming period between 2008 and 2012. Furthermore the Austrian goal is to reach a decrease in value at about 13%.

According to an agreement within the European Union there shall be a considerably decline of emissions until 2020 of 20% minimum in comparison to the value of 1990.

Further periods to restrict the global warming at 2 K until the end of this century are under way (Negotiations Dec. 2009 Copenhagen). The European Union indicated its will to increase their goals up to a percentage of 30% if other Global Players are willing to join.

Embedded in the actual ecological circumstances and according to scientifically discussions it is essential to reduce the emissions at about 80% until 2050 in comparison to 1990 for keeping means of livelihood for future generations.

One relevant factor on the emissions is the building-sector. It is characterised by a lack of inertia to reduce the emission, because of its enormous volume of stock.

The study in hand is an instrument that builds a rudimental basis by the construction of sceneries that should demonstrate which necessary relevant and realistic measures should be implemented in order to reach the mentioned goals.

Approach

Methodical the study in hand is based at a button-up view, using a scenario planning. A status analysis, using data of the “building and flat census 2001” (published by the Statistic Austria 2004), is forming the base of the data building stock and energy mix.

At the same time the austrian aims for climate protection, concerning residential buildings, have been compiled by using the “Climate Protection Report 2008” published by the austrian Umweltbundesamt.

Using a special developed forecast-tool to combine the different parameter for each period of erection enables to predict the further development for all scenarios.

Conclusion

A main conclusion of the study in hand is that the measures of the austrian government to reduce the emission of greenhouse gases for residential buildings won’t succeed in the aspired scale, even if they are completely permuted. It is pointed out, that residential buildings will emit about 24.8% (3.65 million t) more CO₂ than arranged in the Kyoto-agreement at 2012. If the actual trend will proceed, the climate protection aims for 2020 will be failed about 6.9 million t CO₂, respectively 65.7%. Due to this Austria will force the global climate change and will be confronted with massive penalty calculations.

The final energy demand of the austrian residential buildings has reached an all-time high in the last years. At the same time 72% of this demand is provided by fossil energy. The consequences are recurrent bottleneck in supply and continuous rising heating costs. Because of this the grant for heating costs has to be heightened each year. The efforts to raise the quota of renewable energy won’t succeed, as long as the final energy demand is such high. If we won’t refurbish the building stock soon at a high quality standard, but succeed in raising the quota of renewable energy, we will have the problem of a bottleneck in supply even for renewable energy sources.

Pointed out by the study in hand energy-efficiency can solve both before mentioned problems. By reducing the needed energy, fewer emissions are generated as well as the remaining final energy demand can be provided easily by renewable energy sources. Following this way about 6.5 million t CO₂ in 2020 can be saved in comparison to 2008. This means a reduction of 27.9% to 1990. Taking an outlook to 2050 this means 15.9 million t CO₂ less each year compared with 2008. Concerning 1990 this means a reduction of 71.3%.

This underlines the denotation of energy-efficiency as energy source of the future.

The austrian building stock in hole, including the stock of residential buildings in special, is formed by various architectural styles as well as a wide range of different materials and other general conditions of the erection date. Depending on the period of erection and the type of residence (detached house/multi story building) different potentials are forecast. The highest potential is predicted to the detached houses erected in the period 1961-80. Reasons are the bad building standard, a high energy demand, an optimal qualification for high-level thermal retrofitting and the small number of improved buildings till now. Savings of 3.7 million t CO₂ can be realized here in 2050, if the potentials of the Passivhaus-standard at retrofitting are used. Future detached houses have the capability to have saved 1.9 million t CO₂ by 2050, if they are erected in Passivhaus-standard. Multi story buildings erected between 1961-80 have the ability to economize another 1.5 million t CO₂ in 2050. The lower potential, in comparison to the detached houses of this period, grounds on the large number of already badly renovated buildings.

A combination of a high retrofitting rate and a high quality standard forms the base for a successful scenario and are inseparable. If the retrofitting rate is too low, there won’t be ample projects to reach the target. Raising the retrofitting rate without forcing the quality won’t fail only the aims, but it will also delay further qualitative transformations, as the realized ones have to amortize first. Further the inhabitants will refuse sooner changes as they just have been burdened by building measures before.

Beside thermal refurbishments also further buildings have an essential impact on the future emission balance, according to the high demand of new living area. A wrong development at this sector would essentially impair the overall-balance.

Todays situation of the emission- and energy-balance in Austria necessitate rapid and forceful steps to change the status quo. The study in hand points out the spectrum of possible developments, depending on the strategy. Due to the inertia of the building stock it is essential to decide for a rapid and high quality package of measures.

Studienautoren

Ing. Günter Lang / LANG consulting

Mathias Lang / LANG consulting

Im Auftrag der

IG Passivhaus Österreich

Gefördert durch das

Bundesministerium für Verkehr, Innovation und Technologie

Wien, Juni 2009