Energy Model Southtyrol Appendix 2 Refurbishment of residential buildings W. Sparber, D. Moser, M. Prina, U. F. Oberegger, R. Pernetti, G. Garegnani, R. Vaccaro, M. Cozzini
Objectives Establish cost effective refurbishment scenario until 2050 for the residential building stock of South Tyrol Estimate investment cost and energy savings for different energy efficiency measures, building categories and years of construction Base the calculation on monitored or statistical data whenever possible 2
Buildings, surfaces, occupancy level ISTAT statistics
Surfaces dwellings occupied by residents ISTAT census 2011 Municipality Surface [m 2 ] Bolzano 3599095 Merano 1392281 Bressanone 742118 Brunico 570627 Appiano sulla Strada del Vino 555527 Laives 548883 Lana 411759 Caldaro sulla Strada del Vino 309561 Renon 273689 Sarentino 242433 Vipiteno 241521 Castelrotto 222742 Silandro 221414 Valle Aurina 212533 Naturno 204337 Campo Tures 203814...... Millions 4 3,5 3 2,5 2 1,5 1 0,5 0 Surface in square meters % of total surface 50% 40% 30% 20% 10% 0% Total residential surface in South Tyrol: 18,390,738 m 2 Source: http://www.istat.it/it/censimento popolazione/censimento popolazione 2011: superficie delle abitazioni occupate da persone residenti 4
Occupancy level of residential buildings ISTAT census 2011 Number of residential buildings broken down by percentage of occupied dwellings 1464 471 7067 5652 3691 67299 100% occupied 75 100% occupied 50 75% occupied 25 50% occupied 0 25% occupied empty Share of total number of buildings 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Percentage of residential buildings with a certain occupancy level 79% 100% occupied 4% 7% 75 100% occupied 50 75% occupied 2% 1% 25 50% occupied 0 25% occupied 8% empty Number of residential buildings in South Tyrol: 85,644 Source: http://www.istat.it/it/censimento popolazione/censimento popolazione 2011: edifici residenziali per classe percentuale di abitazioni occupate 5
Monitored thermal consumptions EU project Sinfonia
Bolzano district data from Sinfonia project 1384 records Gross surface: 2,251,199 m 2 12% of residential surface in South Tyrol Net surface: 1,868,495 m 2 * District does not contain historic center and industrial zone * Estimated at 83% of total gross surface Source: Sinfonia project, http://www.sinfonia smartcities.eu/en/project 7
Monitored residential heating + DHW consumption Bolzano district data from Sinfonia project Eurac analysis 18% 16% 14% 12% 10% 8% 6% 4% 2% 0% Partially unheated dwellings 10% 9% Specific consumption distribution 5% 8% 15% 15% 14% 14% 3% 1% 2% 0% 0% 3% kwh/m 2 a * * All consumptions in kwh/m 2 a are based on the net surface Reference year: 2010 8
Monitored residential heating + DHW consumption Bolzano district data from Sinfonia project Eurac analysis 30% 20% 10% 0% 5% 5% 6% 10%14% Before 1946 22% 16%12% 4% 2% 1% 0% 0% 3% 9 <10 10 40 40 60 60 80 80 100 100 120 120 140 140 180 180 200 200 220 240 260 260 280 280 300 >300 kwh/m 2 a 1946 1990 394 buildings 850 buildings 20% 13% 14% 13% 14%15% 15% 11% 10% 4% 8% 3% 5% 1% 2% 0% 1% 2% 0% <10 10 40 40 60 60 80 80 100 100 120 120 140 140 180 180 200 200 220 240 260 260 280 280 300 >300 kwh/m 2 a 30% 20% 10% 0% 10% 5% 10% 6% 1991 2005 27% 14% 7% 15% 2% 1% 1% 0% 0% 1% <10 10 40 40 60 60 80 80 100 100 120 120 140 140 180 180 200 200 220 240 260 260 280 280 300 >300 kwh/m 2 a After 2005 84 buildings 9% 9% 11%15%17% 11% 7% 54 buildings 20% 17% 15% 10% 5% 2% 0% 0% 2% 0% 0% 0% <10 10 40 40 60 60 80 80 100 100 120 120 140 140 180 180 200 200 220 240 260 260 280 280 300 >300 kwh/m 2 a Reference year: 2010
Monitored average residential heating + DHW consumption* Bolzano district data from Sinfonia project Eurac analysis 181 1 2 FH: single or two family house MFH: multi family house (small 10 apt, big > 10 apt) Block: apartment block (> 10 apt, > 4 floors) 154 152 kwh/m 2 a 115 114 100 101 97 102 97 89 94 72 67 100 75 1 2 FH SMALL MFH BIG MFH BLOCK Before 1946 1946 1990 1991 2005 After 2005 * After exclusion of outliers Reference year: 2010 10
Uncertainty: specific heating + DHW consumption if 20% of the residential surface in Bolzano were unheated Annual kwh/(m 2 heated surface) 227 193 190 144 142 Increase by 25% 125 126 122 127 121 111 117 90 84 125 94 1 2 FH SMALL MFH BIG MFH BLOCK Before 1946 1946 1990 1991 2005 After 2005 Reference year: 2010 11
Surfaces per building category and construction year EU projects Sinfonia and AlpBC
Residential surface distribution urban area Example of Bolzano district data from Sinfonia project Eurac analysis 60% 50% 40% 30% 3,4% 4,1% 3,7% 2,6% 20% 10% 0% 39,0% 24,1% 0,5% 0,8% 5,9% 0.4% 8,8% 3,1% 3,6% 1 2 FH Small MFH Big MFH Block Before 1946 1946 1990 1991 2005 After 2005 Reference year: 2010 13
Residential surface distribution rural area Example of municipalities St. Leonhard, St. Martin and Moos in Passeier valley Data from AlpBC project Eurac analysis 60% 50% 40% 30% 20% 10% 0% Source: AlpBC project, http://www.it.alpbc.eu/ 2% 9% 29% 12% No apartment blocks 5% 1% 3% 16% 10% 4% 7% 1 2 FH Small MFH Big MFH Before 1946 1946 1990 1991 2005 After 2005 1% Reference year: 2010 14
Residential heating and domestic hot water consumption at Province level Eurac calculation
Computation of residential heating + DHW consumption at Province level assumptions Bolzano and Merano: surface distribution of Bolzano district from Sinfonia project All other municipalities: surface distribution of Passeier valley from AlpBC project Consumption per municipality scaled based on HDD (heating degree days) 12 10 8 6 4 2 0 10,10 5,21 Number of apartments per building Computation based on ISTAT census 2011 4,15 2,94 2,81 2,78 2,75 2,70 2,61 2,59 Source: http://www.istat.it/it/censimento popolazione/censimento popolazione 2011: numero di abitazioni; numero di edifici residenziali 16
Residential surface distribution in South Tyrol Data from Sinfonia and AlpBC project Eurac analysis 40% 35% 30% 25% 20% 15% 10% 5% 0% 0.10% in Bolzano and Merano 6,3% 20,9% 9,0% 1,6% 2.80% in Bolzano and Merano 2,5% 9,1% 4,0% 0,8% 11.0% in Bolzano and Merano 1,8% 4,7% 18,6% 7,6% 13.3% in Bolzano and Merano 1,0% 0,7% 10,6% 1,0% 1 2 FH Small MFH Big MFH Block Before 1946 1946 1990 1991 2005 After 2005 Reference year: 2010 17
Residential heating and DHW consumption in South Tyrol Eurac analysis from ISTAT, Sinfonia and AlpBC data 1.800 GWh/a 1.600 1.400 1.200 1.000 800 600 400 200 0 172 105 395 16 184 399 211 776 13 26 59 77 14 17 230 43 Before 1946 1946 1990 1991 2005 After 2005 1 2 FH Small MFH Big MFH Block Total: 2.74 TWh/a Average: 149 kwh/m 2 a Reference year: 2010 18
Residential heating and DHW consumption in South Tyrol Eurac analysis from ISTAT, Sinfonia and AlpBC data 1.800 GWh/a 1.600 1.400 1.200 1.000 800 600 400 200 0 230 776 395 43 Total: 2.74 TWh/a Average: 149 kwh/m 2 a 26 77 17 59 399 14 13 211 105 172 184 16 1 2 FH Small MFH Big MFH Block Before 1946 1946 1990 1991 2005 After 2005 Reference year: 2010 19
Modelled retrofit cost and energy savings Eurac calculation
Modelled retrofit cost and energy savings Starting from past experiences in building stock analysis in South Tyrol [1, 2]: Definition of a set of building archetypes Focus on one construction period: 1946 1990 (highest renovation potential) typical technical features of that period Four building base models in PHPP (Passive House Planning Package) for evaluating the potential retrofit savings Building features before renovation 1 1 2 FH Small MFH Big MFH Block Surface (m 2 ) 164 473 1123 1448 S/V Ratio 0.76 0.55 0.49 0.36 H[kWh/(m 2 a)] 288 185 158 129 Building features before renovation 2 Wall U [W/(m²K)] 1.269 Floor/ceiling U [W/(m²K)] 1.489 Roof U [W/(m²K)] 1.805 Basement U [W/(m²K)] 1.365 g value [%] 0.770 Windows U g [W/(m²K)] 2.800 U f [W/(m²K)] 2.500 [1] D.Exner, V. D Alonzo, G. Paoletti, R. Pascual, R. Pernetti. Building Stock Analysis for the Definition of Energy Renovation Scenarios at Urban Scale Green Energy and Technology 2016 [2] Giulia Paoletti Analisi del patrimonio edilizio residenziale del Comune di Merano Project Open Energy 21
Modelled retrofit cost and energy savings Type of renovation measures: Wall insulation Roof insulation Insulation of the basement and of the ceiling Installation of new windows 20 simulations for each building typology with two levels of renovation: 10 Standard: minimum requirements for climate zone E (D.M. 26.06.2015) 10 Advanced: towards NZEB (Net Zero Energy Building) Evaluation of: Yearly heating demand [kwh/(m 2 a)] Amount of yearly saving [%] Renovation cost for each kwh saved [ /kwh] Renovation cost for surface unit [ /m 2 ] 22
Modelled retrofit cost and energy savings Improvement of thermal transmittance single layer of insulation (no technical detail) λ insul = 0.04 W/(m K) Retrofit cost is total cost for energy efficiency measure including scaffolding, installation, plaster, painting etc. U [W/(m 2 K)] Standard Advanced S insul [cm] U Cost [ /m 2 ] [W/(m 2 K)] S insul [cm] Cost [ /m 2 ] Wall 0.34 10 87.50 0.16 21 103.00 Floor/ceiling 0.33 10 58.00 0.22 15 68.00 Roof 0.28 12 125.00 0.11 32 136.50 Basement 0.33 10 58.00 0.22 15 68.00 Windows U f 1.60 U g 1.70 450.00 U f 1.00 U g 1.10 585.00 n 50 = 1.50 n 50 = 1.00 Source for renovation costs: Intelligent Energy Europe Passive house retrofit kit (ITALY) 23
Simulations performed in PHPP Standard retrofit Advanced retrofit ID F B R W F B R W 0 1 x 2 x x 3 x x x 4 x x x x 5 x 6 x x 7 x x x 8 x x x x 9 x 10 x x 11 x x x 12 x 13 x x 14 x x x 15 x 16 x x 17 x 18 x x 19 x 20 x F: façade insulation; B: basement insulation; R: roof insulation; W: window replacement 24
Modelled total renovation cost Standard retrofit Advanced retrofit ID 1 2 FH Small MFH Big MFH Block 1 2 FH Small MFH Big MFH Block F B R W F B R W 1 25,900 52,413 103,950 119,963 2 31,700 64,709 135,270 144,149 3 48,015 91,315 203,040 196,482 4 58,410 114,265 272,610 263,397 5 30,488 61,697 122,364 141,213 6 37,288 76,113 159,084 169,569 7 55,033 105,051 232,794 226,490 8 68,547 134,886 323,235 313,479 9 5,800 12,296 31,320 24,186 10 22,115 38,902 99,090 76,520 11 32,510 61,852 168,660 143,435 12 6,800 14,416 36,720 28,356 13 24,545 43,354 110,430 85,277 14 38,059 73,189 200,871 172,266 15 16,315 26,606 67,770 52,334 16 26,710 49,556 137,340 119,249 17 17,745 28,938 73,710 56,921 18 31,259 58,773 164,151 143,910 19 10,395 22,950 69,570 66,915 20 13,514 29,835 90,441 86,990 F: façade insulation; B: basement insulation; R: roof insulation; W: window replacement 25
Modelled retrofit costs and energy savings 1 2 FH Small MFH Big MFH Block ID Q Hnd % sav /kwh /m 2 Q Hnd % sav /kwh /m 2 Q Hnd % sav /kwh /m 2 Q Hnd % sav /kwh /m 2 0 311 185 158 129 1 198 37% 1.39 158 110 41% 1.47 111 106 33% 1.78 93 83 36% 1.81 83 2 191 39% 1.61 193 106 43% 1.73 137 102 35% 2.15 120 81 37% 2.09 100 3 105 66% 1.42 293 75 59% 1.76 193 69 56% 2.03 181 61 52% 2.01 136 4 97 69% 1.66 356 69 63% 2.07 242 62 61% 2.53 243 54 58% 2.45 182 5 174 44% 1.35 186 94 49% 1.44 130 94 40% 1.70 109 72 44% 1.73 98 6 167 46% 1.58 227 90 51% 1.70 161 90 43% 2.07 142 70 45% 2.01 117 7 74 76% 1.41 336 57 69% 1.73 222 54 66% 1.98 207 49 62% 1.96 156 8 60 81% 1.66 418 44 76% 2.03 285 41 74% 2.45 288 36 72% 2.34 216 9 303 3% 3.99 35 180 3% 5.45 26 153 3% 5.25 28 126 2% 6.60 17 10 216 31% 1.42 135 149 19% 2.30 82 119 24% 2.28 88 106 17% 2.36 53 11 208 33% 1.92 198 142 23% 3.07 131 112 29% 3.29 150 99 23% 3.39 99 12 301 3% 3.99 41 179 3% 5.42 30 152 4% 5.15 33 126 2% 6.46 20 13 207 34% 1.43 150 145 21% 2.32 92 115 27% 2.29 98 104 19% 2.37 59 14 193 38% 1.95 232 133 28% 2.96 155 102 35% 3.20 179 91 29% 3.16 119 15 225 28% 1.16 99 154 17% 1.84 56 125 21% 1.83 60 109 15% 1.83 36 16 217 30% 1.73 163 148 20% 2.79 105 118 25% 3.06 122 102 21% 3.10 82 17 218 30% 1.15 108 152 18% 1.82 61 122 23% 1.81 66 107 17% 1.82 39 18 203 35% 1.76 191 139 25% 2.68 124 109 31% 2.98 146 94 27% 2.88 99 19 304 3% 8.08 63 178 4% 6.98 49 151 4% 8.88 62 122 5% 6.79 46 20 297 5% 5.78 82 172 7% 4.94 63 128 19% 2.72 81 116 10% 4.68 60 26
Modelled retrofit costs and energy savings Window replacement Basement insulation 27
Key messages from PHPP simulation results Retrofit measure Investment cost ( /m 2 ) Cost per kwh saved per year Standard window replacement in 1 2 FH 63 8.1 Standard roof insulation in 1 2 FH 99 1.2 Retrofit measures with low investment cost may not always be convenient in terms of /kwh saved per year. In most cases, advanced retrofits are more cost effective in terms of /kwh saved per year than standard retrofits. Retrofit measure Investment cost ( /m 2 ) Cost per kwh saved per year Standard window replacement in 1 2 FH Advanced window replacement in 1 2 FH 63 8.1 82 5.8 28
Development of the cost energy saving curve Assumptions Modelled DHW consumption is 25 kwh/m 2 a * independent of building type, construction period and municipality. A retrofit does not change this amount. Energy saving percentage and retrofit cost are independent of construction period and municipality (but varies according to building type and retrofit measures). The residential building stock in South Tyrol is retrofitted based on /kwh saved per year (from lowest to highest) Only the direct economic benefit from energy savings is considered. The buildings are retrofitted gradually: Facade insulation Roof insulation Basement insulation Window replacement * Source: data provided by SEL. Monitored DHW consumption in the Casanova district in Bolzano in 2012 2013. 29
Retrofit scenario: table of 4200 rows = retrofit steps Retrofit step Construction period Building type Municipality Retrofit action /per annual kwh saved Surface in m 2 Total annual kwh saved Total cost in 1 Before 1946 1 2 FH Corvara in Badia AR 1.16 5991 558427 648,238 2 Before 1946 1 2 FH Selva di Val Gardena AR 1.18 11032 1014658 1,193,677........................... 2252 Before 1946 Small MFH Ponte Gardena AFBR 4.32 313 6638 28,683 2253 After 2005 Big MFH Rio di Pusteria AF 4.32 1239 31229 135,032 2254 1991 2005 Big MFH Falzes AFBR 4.33 4769 108302 468,943........................... 3150 After 2005 Big MFH Appiano sulla Strada del Vino AFBR 7.94 6899 85400 678,404 3151 Before 1946 Small MFH Chiusa AFBRW 7.95 7983 63345 503,527........................... 4199 After 2005 Big MFH Salorno AFBRW 24.34 1666 5514 134,210 4200 After 2005 Big MFH Cortina sulla Strada del Vino AFBRW 24.62 326 1067 26,268 AR: advanced roof insulation AF: advanced facade insulation AFBR: advanced envelope (facade, basement and roof) insulation AFBRW: advanced envelope insulation and window replacement 30
7 Retrofit implementation costs versus annual energy savings 2,5 Cost in billion (cumulative) 6 5 4 3 2 1 Cost Annual consumption 2,0 1,5 1,0 0,5 Annual consumption in TWh 0 0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 Annual energy savings in TWh 0,0 31
25 Investment cost per additional kwh saved 20 per kwh saved 15 10 5 0 0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 Annual savings in TWh 32
Share of total surface 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Retrofit actions by building type 0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 Annual savings in TWh 1 2 FH Small MFH Big MFH Block 33
Share of total surface 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Retrofit actions by construction period 0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 Annual savings in TWh Before 1946 1946 1990 1991 2005 After 2005 34
Retrofit scenarios until 2050 Scenario 1, Business as usual : 56 million invested/year in building stock refurbishment in South Tyrol total investments in 2013 reported by ENEA and Ufficio risparmio energetico of Province of Bolzano [1, 2] Scenario 2: 180 million invested/year necessary for covering 90% of heat demand with renewable energy sources (RES) if heat production from RES stays constant annual heat production from RES in South Tyrol is 1.3 TWh [1] ENEA report on granted tax reliefs for energy conservation measures: http://efficienzaenergetica.acs.enea.it/doc/rapporto55%25_13.pdf [2] Data shared by the Ufficio risparmio energetico. 35
7 6 5 4 3 2 1 0 2,5 2,0 1,5 1,0 0,5 0,0 36 Cost in billion (cumulative) 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 Annual consumption in TWh Scenario 1 Business as usual versus Scenario 2 Annual consumption Cost Implementation year Business as usual cost Scenario 2 cost Business as usual consumption Scenario 2 consumption
Key findings Scenario 1 Business as usual ( 56 million invested/year) is insufficient to reach the Klimaplan target of 90% of the energy need covered by renewables by 2050. Scenario 2 ( 180 million invested/year) reaches the Klimaplan target. It is possible to lower investment cost by combining the accelerated retrofitting program with a further development of the energy generation from renewable energy sources. [1] ENEA report on granted tax reliefs for energy conservation measures: http://efficienzaenergetica.acs.enea.it/doc/rapporto55%25_13.pdf [2] Data shared by the Ufficio risparmio energetico. 37
Sources Sinfonia project: http://www.sinfonia smartcities.eu/en/project AlpBC project: http://www.it.alpbc.eu/ ASTAT: census, www.provincia.bz.it/astat/it/censimento popolazione/ ISTAT: census 2001 and 2011 http://www.istat.it/it/censimento popolazione/censimento popolazione 2011 http://www.istat.it/it/censimento popolazione/censimento popolazione 2001 ENEA: report on granted tax reliefs for energy conservation measures http://efficienzaenergetica.acs.enea.it/doc/rapporto55%25_13.pdf 38
Thanks for your attention Contact us: www.eurac.edu MatteoGiacomo.prina@eurac.edu Tel. +39 0471 055587 39