U-Values for Better Energy Performance of Buildings Study for Eurima Presentation during the Sustainable Energy Week 2008 Brussels, January 08 Thomas Boermans
Quantifying the potential I II III IV & V VI Climate Protection Regulation Cost Effectiveness Enlarged EU Price Scenario
Key figures from these studies 40% Energy 270 billions/y 3.3 million barrels/d 460 millions tons CO 2 /y 530.000 jobs (Eurima estimate) Energy price ref: 70$/barrel
Trias Energetica
Objectives of the study Ecofys VII TO DEFINE the optimum U-values based on economic and environmental criteria, for all countries in Europe. TO INVESTIGATE whether there is room for improvement in reconsidering national requirements (U-values) for building components. TO IDENTIFY the impact of insulation on cooling energy demand in hot climate regions.
Starting point EPBD Energy Performance of Buildings Directive EPBD whole building energy performance National or regional whole building requirements Energy performance requirement per building component in practice + U-values either as design criteria or component requirement Economic optimum Environmental goals
U-value - coefficient of heat transmission (1) 21 C 21 C W/m 2 K low U-value = low energy transfer
U-value - coefficient of heat transmission (2) 21 C 21 C winter low U-value = low energy transfer summer
Insulation & cooling demand in Seville TRNSys: Energy demand cooling Sevilla SFH [kwh/m²a] Insulation: wall 0,6 / roof 0,5 / floor 0,5 W/m²K 60 50 [kwh/m²a] 40 30 20 10 0 reference no shading high int. gains no night vent. low mass without insulation with insulation
U-values - economic optimum Economical parameters: Energy price scenario WEO 2006 Peak Price (Oil: $70 / barrel) Energy mix Investment costs & Interest rate Climatic conditions for 100 cities characterized by HDD and CDD Life cycle costing over a period of 30 years
U-values - climate change IPCC: To keep temperature increase below 2 C, global GHG emissions should decrease by 50% by 2050 compared to 1990 EU commitment: Reduction GHG emissions by 60% - 80% by 2050 Buildings: the highest energy consumer the most cost effective CO 2 mitigation measure technical solutions available should contribute above average The study assumed that buildings should contribute with a reduction of 85% of GHG emissions by 2050
Savings from heating and cooling for one element of the construction Costs + Annual investment costs Insulation thickness* Energy costs cooling + heating = Costs - A negative cost represents a SAVING *Indication of the thermal performance of the element
From cost optimum to U-values Costs + More comfort More sustainable EXISTING HOUSING STOCK Present NEW BUILDING REQUIRE- MENTS U-value 2,00 Example Minimum BEST PRACTICE* 1,50 0,6 0,40 0,30 0,20 0,15 State of the art 0,12 0,10 *Based on oil price study hypothesis
Whole building approach & Passive House Costs + economic optimum roof insulation wall insulation Total energy related investment costs extra for triple glazing/ventilation floor insulation avoidance heating system BEST PRACTICE Costs - Energy savings Passive House optimum
Whole building approach & Passive House Costs + economic optimum roof insulation wall insulation Total energy related investment costs extra for triple glazing/ventilation BEST PRACTICE Passive House floor insulation concept is not avoidance heating system considered in the study Costs - ECOFYS VII Energy savings Passive House optimum
Roof insulation current and optimum (1) < 0,14 W/m²K >0,59 W/m²K Present U-values WEO2006 scenario
Roof insulation current and optimum (2) < 0,14 W/m²K >0,59 W/m²K Present U-values Peak price scenario
Comparison wall, roof and floor insulation (1) Present U-values WEO 2006 scenario
Comparison wall, roof and floor insulation (2) Present U-values Peak price scenario
U-values comparison U-values Stockholm U-values Amsterdam WEO 06 Peak price Post Kyoto building reg. WEO 06 Peak price Post Kyoto building reg. 0,6 0,6 0,5 0,5 0,4 0,4 [W/m²K] 0,3 [W/m²K] 0,3 0,2 0,2 0,1 0,1 0,0 wall roof floor 0,0 wall roof floor U-values Warsaw U-values Seville WEO 06 Peak price Post Kyoto building reg. WEO 06 Peak price Post Kyoto building reg. 0,6 1,6 [W/m²K] 0,5 0,4 0,3 0,2 0,1 [W/m²K] 1,4 1,2 1,0 0,8 0,6 0,4 0,2 0,0 wall roof floor 0,0 wall roof floor
Conclusions (1) In 2007, most requirements for U-values for wall, roof and floor in new buildings are below the economic optimum -> Cost saving opportunities are lost for households as well as for society U-values recommended in the study are valid for new as well as for existing buildings -> There is room for improvement for new AND for existing buildings
Conclusions (2) Almost identical recommended U-values, for maximum cost effectiveness and for post Kyoto targets -> Good economy and climate protection are not contradictory. Fast action needed for 2020/2050 targets. Insulation (especially roof and wall) reduces energy demand for cooling of residential buildings -> This adds a new perspective to insulation in Southern Europe.
Further information Ecofys Germany, Cologne Tel +49 (0)221 510907-0 info@ecofys.de www.ecofys.de Avenue Louise 375, Box 4 B-1050 Brussels, Belgium Tel +32 (0)2 626 20 90 www.eurima.org