Cost-benefit analysis of energy efficient measures in buildings Piia Sormunen D,Sc (in Tech) Head of competence center, Energy smart environment, Metropolia Helsinki University of Applied Science
2021 New buildings are nearly zero energy buildings (public buildings 2019) EU Member States faced new tough challenges. We are moving towards new and retrofitted nearly-zero energy buildings by 2020, 2018 in the case of public buildings
THE IMPORTANCE OF LCC AND LCA ANALYSIS INCREASE DUE BUILDING CODES FOR NEARLY ZERO ENERGY BUILDINGS (EPBD) AND FUTURE ZERO CARBON BUILDINGS Source: FInZEB nzeb targets and methodology development in Finland, Jarek Kurnitski
Source: Jarek Kurnitski
E-value in Finland 2015 Bought energy Heat 40 kwh/m² Cooling 8 kwh/m² Electricity 48 kwh/m² Primary energy factor Discrict heating 0,7 Standard utilisation Discrict cooling 0,4 Electricity 1,7 E-value 40 kwh/m² * 0,7 + 8 kwh/m² * 0,4 + 48 kwh/m² * 1,7 = 116 kwh/m² Primary energy factor Fossil 1 Electricity 1,7 Discrict heating 0,7 Discrict cooling 0,4 Renewable 0,5 Limit in building code 2012 Office 170 kwh/m² 2018 building code Office 90 kwh/m²?
LIFE CYCLE DESIGN Life cycle design is the basis for sustainable building design The main aspects of life cycle design are 1. Balance of indoor environment and energy efficiency in the building 2. Ensuring long life cycle of the building 3. Fundamental understanding of building physics
Aesthetics Life style Business culture Architectural styles Image Building traditions Culture aspects Economical aspects Non- construction costs Life cycle costs Income Investment cost Construction cost Maintenance costs Operation costs End of Life costs Energy consumption Renewable energy use Primary energy consumption Energy source emissions Energy certificate class Use of energy Ecological aspects Life cycle design (Sustainable design) Human aspects Health Indoor environment Safety and security Comfort Flexibility & adaptability Fire safety Security systems Operational reliability Water resource Eco materials Raw material Functional aspects Expandability Maintainability Technical aspects Durability Serviceability Reliability Recyclable materials Water Air Soil Use of water Waste Biodiversity Pollution Target setting! Concurrent design! Legal aspects National regulations National standards Local regulations Adapted from InPro Task 2.5
Indoor conditions LIFE CYCLE ANALYSIS IS DECISION MAKING TOOL IN BUILDING DESIGN Early design phase Design phase Construction Target setting Design alternatives Hand-over Target management Indoor targets for room spaces Comparisons of different design solutions Indoor conditions Dynamic calculations (Magicad comfort and energy Ida-Ice, IES VE-Pro Comparisons of different design solutions Ari flows, loads - heating, cooling CFD Computational fluid dynamics Challenging spaces - Temperature, air flows Challenging spaces - Air distribution in different utilisation Energy Dynamic energy simulation Target for energy consumption Comparisons of different design solutions Energy consumption of design solution Target for utlilisation phase Source: Granlund Oy
LIFE CYCLE ANALYSIS IS DECISION MAKING TOOL IN BUILDING DESIGN Early design phase Design phase Construction Target setting Design alternatives Hand-over Environment and life cycle LCA Life cycle assessment PROMISE-LUOKITUS A B C D E Target setting - LEED, Breeam, CO2-eqv C Comparisons of different design solutions Design phase (LCA, LEED, BREAAM) LCA LEED, BREAAM class LCC Life cycle cost Target setting - Investment costs - Maintanance - Utilisation costs - Life cycle costs El i nkaari kustannukset [ ] 120000 1 0000 800 00 600 00 400 00 200 00 0 ELINKAARIKUSTANNUKSET, NYKYARVO Perustapaus Vertailutapaus Comparisons of different design solutions Utilisation costs Level - Building - System - Components Level - Building - System - Components Usually different systems or components are compared and LCC analysis gives information for decision making during design process
LCC -LIFE CYCLE COST ELINKAARIKUSTANNUSLASKELMA LIITE 3 KUSTANNUSVERTAILU Asiakirja n:o HUS-HALLINTOKESKUS Projekti n:o H04568.P014 RUOKALAN IKKUNAVERTAILU Pv m. Laatija/Tark. Viim. muutos Laadittu 28.11.2008 KBa Tarkastelujakso: 20 a Ala: 470 brm² Laskentakorko: 4,0 % Kuvaus: Ikkunoiden uusinta/kunnostus 1.Ikkunat korjataan 2. Ikkunat uusitaan U=1,0 W/m²K Elinkaarikustannukset, nykyarvo [ ] Yhteensä Investointi PTS - kunnossapito Korjaukset M ääräaikaishuollo t Energia M uu 1. 120 400 46 200 0 0 0 74 155 0 2. 117 600 63 360 0 0 0 54 282 0 3. 0 0 0 0 0 0 0 4. 0 Elinkaarikustannukset [ ] Elinkaarikustannukset [ ] 140 000 120 000 100 000 80 000 60 000 40 000 20 000 0 140 000 120 000 100 000 80 000 60 000 40 000 20 000 KUMULATIIVISET ELINKAARIKUSTANNUKSET 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Vuosi [a] 1. Vanhat ikkunat kunnostetaan 2. Ikkunat uusitaan kolmikerroslämpöelementti selektiivilasilla + argon U-arvo =1,0 W/m2,K 0 ELINKAARIKUSTANNUKSET, NYKYARVO 1 2 3 4 Investointi PTS - kunnossapito Korjaukset Määräaikaishuollot Energia Muu Costs 1. Investment 2. Maintanance and repairs 3. Utilisation (energy, water) 4. Others Initial values Period 20 years Interest rate 4 % Method Net Present Value Equivalent Annual Cost Direct pay-back time 10
EXAMPLE OF LCC ANALYSIS Window type Insulation of exterior walls and roof Systems (mechanical ventilation, natural ventilation, cooling) Building automation systems Heat recovery systems Components (lighting, pumps and fans) Energy sources (renewable energy sources, heat pumps, discrict heating and cooling) 30 000 KUMULATIIVISET ELINKAARIKUSTANNUKSET 25 000 Elinkaarikustannukset [ ] 20 000 15 000 10 000 5 000 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Vuosi [a] 1. Vesikiertoinen lattialämmitys 2. Sähköinen lattialämmitys 11
PASSIVE HOUSES Cost benefit analysis Energy source 1/2 30 passive houses Rented flats Period 20 years Alternatives Boiler: wood, pellets, oil Discrict heating (2 km to main line) Heat pumps- ground heat, exhaust heat pump, air/water heat pump in area scale or building scale Renewable energy, solar heating, PVs, wind
PASSIVE HOUSES Cost benefit analysis Energy source 2/2 400 000 district heating 350 000 Exhaust air heat pump Cumulative NPV [ ] 300 000 250 000 200 000 Boiler, wooden chips Ground source heat pumps 150 000 100 000 Oil 50 000 Electricity 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1. rakennuskohtainen ilma-vesi lämpöpumppu 2. maalämpöpumppu lämpölaitos 3. hakelämpölaitos 4. pellettikattila 5. Sähkölämmitys 6. öljykattila 7. kaukolämpö 8. poistoilmalämpöpumppu Vuosi [a] What was the investor choice?
SCHOOL BUILDING RENOVATION - WINDOWS 1. Windows will be painted and sealed. U=3,30 W/m2K, g-value 48 % 2. Windows will be repaired+ additional glass U= 1,28 W/m2K, g-value 33,5 % 3. New window U= 0,82 W/m2K, g- value= 38,5 % Estimated investment costs Nykyisten ikkunoiden huoltomaalaus U= 3,3 W/m 2 K 126,- 85 600,- Ikkunat kunnostetaan lisälasin kera U= 1,28 W/m 2 K 302,- 205 360,- Uusi ikkuna U=0,82 W/m 2 K 220,- 149 600,- Uusi ikkuna U= 0,60 W/m 2 K 330,- 224 400,- 4. Energy efficient window U=0,60W/m2K, g-value=50,4 % Built in 1965, located in Helsinki
SCHOOL BUILDING RENOVATION - WINDOWS Period n 30 years Interest rate i 4 % Heating energy 40,00 /MWh Investment [ ] Heating energy [MWh] Energy cost [ ] Equivalent annual cost [ /year] NPV [ ] 1. Repaired (painting+sealing) 85600 701 28040 32 990 570 469 2. Repaired +add. Glass 205360 638 25520 37 396 646 653 3. New window U=0,82 149600 559 22360 31 011 536 250 4. New window U= 0,60 224400 533 21320 34 297 593 066 15
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