Cost-optimal energy retrofitting of apartment buildings. Janne Hirvonen Juha Jokisalo, Juhani Heljo, Risto Kosonen

Transcription

1 Cost-optimal energy retrofitting of apartment buildings Janne Hirvonen Juha Jokisalo, Juhani Heljo, Risto Kosonen

2 Background EU targets: significant emissions reductions needed -4% by 23-8% by 25 Energy Performance of Buildings Directive (EPBD) nzeb requirements Most buildings have been built in the 197s and 198s Energy renovation Apartment building ages

3 Research questions How much can emissions be reduced in Finnish apartment buildings by doing energy renovation? What are the cost-optimal and maximum performance solutions? Thermal insulation, heat recovery, solar energy, windows? How do the solutions differ with respect to building age?

4 Building information AB1: <1976 Mechanical exhaust ventilation, no heat recovery AB2: Mechanical exhaust ventilation, no heat recovery AB3: Mechanical supply-exhaust ventilation, heat recovery AB4: 21< Mechanical supply-exhaust ventilation, heat recovery Heating system options District heating GSHP + electric boiler EAHP + district heating

5 Simulation-based optimization Minimize LCC Minimize emissions

6 AB1 District heating, optimal solutions PV Windows Roof insulation Sewage HR Emissions (kg-co 2 /m 2 /a) Optimal case # Electricity import DH import Walls Roof Windows Doors Ventilation HR ST PV HP DH system Sewage HR DBV Radiators Emissions

7 AB1 District heating, optimal solutions PV Windows Roof insulation Solar thermal Sewage HR Emissions (kg-co 2 /m 2 /a) Optimal case # Electricity import DH import Walls Roof Windows Doors Ventilation HR ST PV HP DH system Sewage HR DBV Radiators Emissions

8 AB1 District heating, optimal solutions Wall insulation PV Windows Roof insulation Solar thermal Sewage HR Emissions (kg-co 2 /m 2 /a) Optimal case # Electricity import DH import Walls Roof Windows Doors Ventilation HR ST PV HP DH system Sewage HR DBV Radiators Emissions

9 AB1 District heating, optimal solutions Wall insulation Door insulation PV Windows Roof insulation Solar thermal Sewage HR Emissions (kg-co 2 /m 2 /a) Optimal case # Electricity import DH import Walls Roof Windows Doors Ventilation HR ST PV HP DH system Sewage HR DBV Radiators Emissions

10 AB1 District heating, optimal solutions Mechanical ventilation and heat recovery Demand-based ventilation Wall insulation Door insulation PV Windows Roof insulation Solar thermal Sewage HR Emissions (kg-co 2 /m 2 /a) Optimal case # Electricity import DH import Walls Roof Windows Doors Ventilation HR ST PV HP DH system Sewage HR DBV Radiators Emissions

11 (kg-co 2 / m 2 /a) (kg-co 2 / m 2 /a) (%) ( -LCC/ kg-co 2 / m 2 /a) ( /m 2 / 25a) ( /m 2 ) U-values (W/m 2 K) (m 2 ) (kw p ) (kw th ) ( C) Solution type Emissions Emission reduction Relative reduction Reduction cost LCC Investment cost Walls Roof Doors Windows ST PV HP Ventilation Radiators Sewage HR Apartment building (AB1) with district heating (DH) a HR+DBV 7/4 Active HR b HR+DBV 7/4 Passive HR c No HR 7/4 Active HR d No HR 7/4 Passive HR Ref No HR 7/4 No HR Apartment building (AB1) with an exhaust air heat pump (EAHP) and district heating backup a No HR 45/35 Active HR b No HR 7/4 Active HR c No HR 7/4 Active HR d No HR 7/4 Active HR Apartment building (AB1) with a ground-source heat pump (GSHP) and electric backup heating a HR+DBV 45/35 Passive HR b HR+DBV 45/35 Passive HR c No HR 45/35 Active HR d No HR 7/4 Passive HR

12 Emissions vs. LCC a b c d Emissions (kg-co 2 /m2/a) AB1 DH Ref AB1

13 Emissions vs. LCC a a b b c d c d Emissions (kg-co 2 /m2/a) AB1 DH AB1 EAHP Ref AB1

14 Emissions vs. LCC a a a b b b c d c c d d Emissions (kg-co 2 /m2/a) AB1 DH AB1 GSHP AB1 EAHP Ref AB1

15 Emissions vs. LCC Emissions (kg-co 2 /m2/a) AB1 DH AB1 GSHP AB1 EAHP AB2 DH AB2 GSHP AB2 EAHP Ref AB1 Ref AB2

16 Emissions vs. LCC Emissions (kg-co 2 /m2/a) AB1 DH AB1 GSHP AB1 EAHP AB2 DH AB2 GSHP AB2 EAHP AB3 DH AB3 GSHP Ref AB1 Ref AB2 Ref AB3

17 Emissions vs. LCC Emissions (kg-co 2 /m2/a) AB1 DH AB1 GSHP AB1 EAHP AB2 DH AB2 GSHP AB2 EAHP AB3 DH AB3 GSHP AB4 DH AB4 GSHP Ref AB1 Ref AB2 Ref AB3 Ref AB4

18 Emission reduction vs. reduction cost Emissions reduction cost ( -LCC/kg-CO 2 /a) 25, 22,5 2, 17,5 15, 12,5 1, 7,5 5, 2,5, -2,5-5, -7,5-1, Emissions reduction (kg-co 2 /m 2 /a) AB1 DH AB1 GSHP AB1 EAHP AB2 DH AB2 GSHP AB2 EAHP AB3 DH AB3 GSHP AB4 DH AB4 GSHP

19 Heat generation of chosen solutions

20 Conclusions Apartment building emissions can be reduced by 7-8% Investment cost 27 5 /m 2 Typical pipe renovation cost /m 2 District heated houses can reduce emissions by 3% without raising life cycle costs Investment cost 6 16 /m 2 Heat pump solutions allow cost-effective reduction of 6-8% Investment cost 1 3 /m 2 Cost-effective retrofit solutions All buildings: Solar energy and sewage heat recovery Old buildings: Roof insulation, window retrofit New buildings: Demand-based ventilation