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Explore strategies to reduce CO2 emissions in buildings through the Target Emission Rate and compliance packages. Learn about energy points scale and passive house standards, managing the real world's complexities.
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Cracking the Code:Energy and CO2 Malcolm Bell Buildings, Energy and Sustainability Group, School of the Built Environment, Leeds Metropolitan University, Leeds, UK. Paper presented to: The Code for Sustainable Homes: Cracking the Code Seminar - 14 March 2007, Birmingham, UK.
Target Emission Rate – the TER partially offsets higher carbon intensities of fuels other than gas (electricity, oil, lpg etc. Target Emission Rate kg (CO2)/m2/a CO2 emissions for lighting TER = (CH x fuel factor + CL) x (1- Improvement) CO2 emissions for ventilation, and space & water heating for the notional dwelling Improvement factor = 0.2 i.e. a 20% reduction
- 10% - 18% - 25% - 44% circa -135% to -150% ?? TER - Threshold values
TER – Threshold compliance packages 80m2 Semidetached 2 storey house
TER-06 - electricity TER-06 - gas & bio TER – Base Case Bio: would meet the threshold for 4 Star = 12.9 code points
TER-06 - electricity TER-06 - gas & bio TER – 1 (-10%)
TER-06 - electricity TER-06 - gas & bio TER – 2 (-18%)
TER-06 - electricity TER-06 - gas & bio TER – 3(-25%) Actual = 24 Target = 24.77
TER-06 - electricity TER-06 - gas & bio TER – 4(-44%) Actual = 17 Target = 18.49
Source: Wall (2006), Photo: Hans Eek Airtightness 1 m/h Passive House Standards Timber frame scheme Göteborg, Sweden (120 m2) MVHR – 80% with duct heaters 5m2 Solar water + resistance top-up
Passive House Standards Timber frame scheme Göteborg, Sweden Source: Wall (2006), Photo: Hans Eek TER (kgCO2/m2) Design ≈ 10.6 Actual ≈ 15.3 Under Swedish conditions! Source: Wall (2006), Energy and Buildings. 38, pp 627-634
TER-06 - electricity TER-06 - gas & bio TER – 5(-100%) Net TER = 0
Appliances TER – 6(-135% to -150%)
The place of energy & CO2 One of many scenarios Note: “Other energy” is modelled to balance TER & other energy points in each class
Models and Management Stafford Beer’s presidential address to the Society for General Systems Research at the Annual Meeting of the American Association for the Advancement of Science, 1971 (Beer 1973)
? Model Reality Management Managing the world
Management Model ? ? Reality Time The effects of time
Hidden air paths Behind plasterboard
Hidden air paths Internal partitions
Thermal bridging & construction Designed performance is almost always degraded
Ψ value = 0.068 W/mK Ψ value = 0.180 W/mK As Designed = 42mm gap Typical As Built = 20mm gap +164% Construction issues: window lintel
Party wall heat bypass Understanding complex heat loss paths
? Only if we use it to manage the real world Cracking the Code?