Finnängen – Swedens first renovated plusenergy house

The path to energy-neutrality

Andreas Molin

Linköpings Universitet

Agenda

• Energy efficiency measures at Finnängen

• Why?

Finnängen – before renovation

• U-value (W/m2K)

– Wall 0,40

– Roof 0,32

– Ground 0,6/1,6

– Window 3

• Infiltration 800 l/s @ 50Pa (300m2)=2,67 l/s,m2

• Ventilation- Mech. Exhaust air + Firing

• Heating — Hydronic – Bio-mass pellet

• Space heating demand -30 000 kWh/yr

• Domestic hot water demand -5 000 kWh/år

• Electricity -5 000 kWh/år

– Household -4 000 kWh/år

– Building electricity -1 000 kWh/år

Myresjöhus-1976

Finnängen

Insulation 25 cm Air-tightness Windows

Solar Thermal - 11m2

Photovoltaic - 10 kW-68m2

Seasonal heat storage- Ground coil-100 m

Horisontal ground coil – 200 m

Solar tank-800l

HRX Ventilation

Grid Hydro power

Heat pump-6kWth

2010-04-28

Air-tightness is acheived by membrane 0,3 ACH (0,13 l/s,m2) at 50 Pa

Passive house standard:

0,6 ACH (0,3 l/s,m2)

Thermal comfort - windows • Comparison surface-temperature inside @ 10°C out

• Older Newer

• 16°C 20,5°C

Thermal comfort important when doing energy

efficiency measures.

Otherwise rebound-effect

Grey EPS Lambda 31 mW/mK

Long service life & form stability

Smart heat storage • Use super-heating of the heat

pump condenser • No need of electric resistance

heating for hot water • Heating with low primary

temperature gives high SPF • Low primary heating temp. :

– Increased insulation – Better air-tightness – Increased convection area – Ventilation heater

• Potential SPF 5

– Condensation at 30 ° – Hot water becomes 50-60 °C. – No legionella problems

60-90°

25-35°

10-25°

Can be used for increased perfrmance in District heating

systems

Lowers return temperature = higher electricity/heat ratio

Modeling Heat

Validation Prognosis

Modeling Electricity

Follow-up: www.ppam.se/blog

Air-tightness will be tested after 1 yr.

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Acc. Electricity Consumption 2011

Electricty consumption

Solar prod Buy

Januari 1283 -98 1185 Februari 959 -410 549 Mars 641 -854 -213 April 352 -1096 -744 Maj 323 -1368 -1045 Juni 260 -1288 -1029

Before • U-value (W/m2K)

– Wall 0,40 – Roof 0,32 – Ground 0,6/1,6 – Window 3

• Infiltration 800 l/s @ 50Pa (300m2)=2,67 l/s,m2

• Ventilation-Mech exhaust+Firing • Heating- Bio-mass pellets • Heating -30 000 kWh/år • Hot water -5 000 kWh/år • Electricity -5 000 kWh/år

– Household -4 000 kWh/år – Building -1 000 kWh/år

After • U-value(W/m2K)

– Wall 0,10 – Roof 0,08/0,10 – Ground 0,6/1,6 – Window 0,77

• Infiltration 60 l/s @50 Pa (454m2)=0,13 l/s,m2

• Ventilation- HRX • Heating-Solar Thermal/heatpump • Heating -10 000 kWh/år • Hot water -5 000 kWh/år • El +2 000 kWh/år

– Household -3 000 kWh/år – Building -1 000 kWh/år – Heat pump -3 000 kWh/år – Solar el. +9 000 kWh/år

Annual use 10ton Pellets & - 5000 kWh el

=> +2000 kWh el

2 sept 2010, Solar power commisioned

2010-12-23, Winter view, ~2%of annual power lost due to snow

2011-01-07 Heat pump commisioned

Life-Cycle Zero Energy Buildings (LC-ZEB)

• Embodied energy

• Operational energy use + embodied energy = 0

• Operational energy use must be negative.

– Finnängen 7000kons-9000prod=~-2000kWh/yr

• LC-ZEB will be acheived after certain years

– (ex 100 000 kWh/ 2 000 kWh = 50 år)

• Focus will be choice of materials & service life

• Older buildng embodied energy must be handled

• Competition: Which building will first be LC-ZEB?

Agenda

• Energy efficiency measures at Finnängen

• Why?

Why all the Kyoto-pyramid at once?

Air-tightness must be planned

Finding more development making use of the old building

Renovation plan: make efficiciency measures when maintenance is needed &

plan for air-tightness

Planetary boundaries:

Exploring the safe operating space for humanity

Rockström et al, 2009

Rockström et al, 2009 http://www.stockholmresilience.org/planetary-boundaries

Why LC-ZEB on 150m2?

-Biofuels needs vast amount of land

-Affects the nitrogen

cycle when combusted

-Bio-diversity loss with bio

Solar power= minimum pollution = no effect on nitrogen cycle

Building solar power= non-exploiting = no effect on bio-diversity

Good potential

Roof & facades in Sweden: 660 km2

PV power: 20-80 TWh,

Depending on system efficiency, demanded rate of return. (Kjellson, 2000)

Why solar power on building =>

decreased biodiversity loss

Problem in Sweden: Sold electricity is less valued due to tax

Elforsk 10:93

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Energiskatt

Elcertifikat

Elnätavgift

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Todays system optimises economy for

small systems

Annual net-billing => Uses the full roof=> Decreased exploitation for energy=> Decreased bio-diversity loss

However: Higher value of solar power than average power

• A. Molin, P. Rohdin, B. Moshfegh.

• Positive power market value for gridconnected roof-top solar power in Sweden”.

• 11th World Renewable Energy Congress and Exhibition, Abu Dhabi, United Arab Emirates, 25 - 30 September 2010.

Night-time lower price

Daytime higher electricity price

+2% +11%

+23% Similar to Carbon Savings:

An investigation of the impact of time of generation on carbon savings from PV systems in Great Britain. P. A. Burgess1,*, M.M. Vahdati 2, D. Davies 3

TACK Andreas Molin

andreas.molin@liu.se

Skype: andreas.molin Mobile: +46-706-935097

Solar blogs :

www.ppam.se/blog bengts.blogg.viivilla.se

Solar Combined PV/T Kombinerad solcell/solfångare

• Maximal användning av solenergi

• Ökad elproduktion vid kylning med energibrunn eller markvärmelager

• Snöavtäckning med frivärme ifrån energibrunnen

• +100-200 kWhel/kWt,år • Återladdar

energibrunn/markvärme • Laddar

varmvattenberedaren

Integrated photovotaics can minimize costs

• 60% cost is in module and system

• Installation- & material-cost can be minimised with BIPV

Source: Elforsk 10:94

Annual net billing gives more investment VAT Investment-VAT more important, than energy tax/kWh

Årsnettning ger större anläggningar & mer investeringsmoms till staten

Elforsk 10:93

How to acheive 5% of Linköpings

Investeringsstöd => ej produktionsoptimerade anläggningar

Alternativt förslag

• Multipel på elcertifikat

– Sol kWh*10 (icke exploaterande)

– Sol kWh*5 (exploaterande)

• Garanteras i 10 år

• Sänk multipel med 10% varje år

• Återbetalning 8-24 år

• Antaget alternativt elpris= Ränta & inflation

• De bästa anläggningarna betalar av sig inom 10 år och blir ”lönsamma”.

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