tim fenn rima international conference invited presentation 2014
TRANSCRIPT
Predicted Annual Energy Costs 100m2 House UK 2013
I-RIM Conference 2014
Annual Predicted Energy Cost: Gas & Electric
Victorian House
1990's House Passivhaus
Electricity £600 £600 £463Lighting £104 £104 £10Hot Water £340 £340 £170Heating £1,000 £520 £60
Total £2,045 £1,565 £703
Annual Heating Demand
I-RIM Conference 2014
Victorian House 250KWh/m2/yr 1990's House 130KWh/m2/yr Passivhaus 15KWh/m2/yr
Gas 0.04 1000 520 60
Oil 0.05 1250 650 75
Electric 0.15 3750 1950 225
£250
£750
£1,250
£1,750
£2,250
£2,750
£3,250
£3,750
Annual Heating Cost (100m² house)
Annual
Cost
£
Annual Hot Water Demand
I-RIM Conference 2014
Cost\KWh £ Victorian House 8500 KWh/yr Annual £
Low Energy House 4250 KWh/yr Annual £
Hot Water Gas 0.04 340 170
Hot Water Oil 0.05 425 212.5
Hot Water Electricity 0.15 1275 637.5
£100
£300
£500
£700
£900
£1,100
£1,300
Annual Hot Water Demand and Cost
Annual
cost
£
Target Killers:
I-RIM Conference 2014
• What can you achieve with what building?
• How much do you want/can afford to spend? & remember 1st 50% easy.
• What planners/conservation officers will allow?
• What your neighbours will allow or not do?
• Site constraints?
Target Killer: Building Envelop
I-RIM Conference 2014
• Insulation installation The GAP!
• Piercing vapour barrier
• Insulating pipework & thermal stores
• Pipework runs
• Incorrect materials
Target Killer: Materials
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• Wet insulation will not perform!
• Deterioration in insulation performance over time?
• Durability of tapes?
• Wet building may take time to perform to its design spec?
Software Limitations
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In both SAP & PHPP• Sunspaces ignored
• Radiant barriers ignored
• Thermal mass?
• Air leakage?
SAP VS PHPP
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November December January February0
1000
2000
3000
4000
5000
6000Total Energy Consumption at Bakers Shaw
PHPP
Actual
SAPkWh
Wall Temperature Gradient
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0
5
10
15
20
25
InsideFoil FrontFoil BackHempGreen WallOutside
3rd Feb 11th Feb
February Average Temperatures Benson
Conclusions
I-RIM Conference 2014
• Vapour barrier\reflective foil (if installed correctly!) adds significant improvement to building envelop performance better than predicted via software
• Vapour barrier/reflective foil leads to highest levels of air-tightness in otherwise leaky buildings
• UK needs more in situ research to understand gaps in performance