the road to zero carbon - building...
TRANSCRIPT
History of Road Map to Zero Carbon
• 2006 - Labour Government introduced revision to Part L
• At the same time Zero Carbon roadmap defined
• By 2016 all new dwellings will be ZERO CARBON
• Part L & SAP (Standard Assessment Procedure) tools to measure Zero Carbon
• July 2010 - current Government confirm commitment to Zero Carbon dwellings
Time Line to Zero Carbon
• Part L 2006 defined B Regs compliance via CO2 targets
• 2010 - CO2 target increase by 25%
• 2013 - CO2 target increase by 44%
• 2016 - All new dwellings to be ZERO CARBON
Definition of Zero Carbon
• Part L 2006 defined Zero Carbon to include regulated & unregulated emissions
• Regulated – Emissions from space & water heating and fixed lighting (include within B Regulations)
• Unregulated – Emissions from cooking & plug in equipment (TV, white goods, Play Station etc.)
Regulated or Un-Regulated
• Unregulated emissions contributes approx 40% to 50% of total CO2 emissions
• March 2011 - Government redefined Zero Carbon to only include regulated emissions
Factors to Deliver Zero Carbon
• High performance thermal envelope – U values, thermal bridging, air tightness and orientation
• Efficient equipment – Boiler (fuel type important), controls, ventilation and lighting
• Renewables– Photovoltaic panels, solar thermal, heat pumps, etc. (have to generate electricity)
How CO2 Emissions are Calculated Within SAP
• All emissions are a function of calculated energy consumption multiplied by the fuel carbon factor
• Space heating – function of thermal envelope performance, boiler efficiency & controls
• Water heating – function of floor area
• Lighting – function of floor area
AREA U
VALUE
Ground Floor 0.16
External Wall 0.20
Roof 0.09
Party Wall 0
Windows 1.4
Doors 1.0
U VALUES
Thermal Mass: Medium
Air Permeability: 5
Thermal Bridging to ACD
HEATING & HOT WATER
Gas fired condensing boiler min SEDBUK 89% Cylinder 150 litres
Radiators Time and temperature zone control & load
compensator
VENTILATION & LIGHTING
Extractor fans (X3) 100% LEL
TFATFA
DER 20.38kgCO₂/m²/yr
TER 20.38kgCO₂/m²/yr
TFA of house 60m² Semi-detached
East/West orientation
SAP2009 compliance
The BBS House
1
AREA U
VALUE
Ground Floor 0.16
External Wall 0.20
Roof 0.09
Party Wall 0
Windows 1.4
Doors 1.0
U VALUES
Thermal Mass: Medium
Air Permeability: 5
Thermal Bridging to ACD
HEATING & HOT WATER
Gas fired condensing boiler min SEDBUK 89% Cylinder 150 litres
Radiators Time and temperature zone control & load
compensator
VENTILATION & LIGHTING
Extractor fans (X3) 100% LEL
TFATFA
DER 16.30kgCO₂/m²/yr
TER 20.38kgCO₂/m²/yr
TFA of house 60m² Semi-detached
East/West orientation
PV =
0.55kWpeak 4.4m2
SAP2012 compliance
The BBS House
2
AREA U
VALUE
Ground Floor 0.16
External Wall 0.20
Roof 0.09
Party Wall 0
Windows 1.4
Doors 1.0
U VALUES
Thermal Mass: Medium
Air Permeability: 5
Thermal Bridging to ACD
HEATING & HOT WATER
Gas fired condensing boiler min SEDBUK 89% Cylinder 150 litres
Radiators Time and temperature zone control & load
compensator
VENTILATION & LIGHTING
Extractor fans (X3) 100% LEL
TFATFA
DER 0kgCO₂/m²/yr
TER 20.38kgCO₂/m²/yr
TFA of house 60m² Semi-detached
East/West orientation
SAP 100% Improvement
PV = 2.8kWpeak
20m2
Zero Carbon 2016
The BBS House
Floor Area to PV area ratio
3 : 1 3
Changes to Part L 2013
• Dwelling emissions target with new Fabric Energy Efficiency Standards (FEES)
• FEES target to ensure ‘renewables’, or low carbon technologies, are not introduced to compensate for thermally inefficient building fabric
• FEES will be measured in kWh/m2/year
• FEES target will vary for dwelling type – detached, mid terrace, flats etc.
Changes to Part L 2013
• Consultation document indicates discrepancy between calculated & as built dwelling performance
• As a result, confidence factors to be included with SAP results
• If a prescribed quality assurance scheme is not followed during design & build, 3% is added to the results
Technologies to Improve SAP Results
Fabric improvements:
• Thin joint internal blockwork
• Triple glazed windows (U values below 1.0)
• Full fill PIR – Xtratherm
• SIP systems
Technologies to Improve SAP Results
Low Carbon Technologies:
• Gas or liquid Biomass CHP - district heating system
• Biomass boilers
• MVHR ventilation systems
• Boiler flue & waste water heat recovery systems
• Ground or air source heat pumps
• Fuel cells
Zero Carbon 2016 – ‘Allowable Solutions’
• Studies have confirmed that not all dwelling types will be able to achieve Zero Carbon – can not fit the required PV on the roof !!!
• Proposal is that ‘Carbon Compliance’ target is met on site via fabric & renewables (targets currently being debated)
• Then ‘allowable solutions’ will mitigate the remaining CO2 emissions
What are Allowable Solutions?
• Local Planning Authority to have prescribed allowable solutions
• Or the developer pays into a private energy fund
• Both of the above will have associated verification & certification procedures that will need to be approved by Building Control
Ashford Carbon Fund
• One-off contribution into Ashford Carbon Fund
• Current charge £28.50 per tonne of CO2. Increases by 2% per annum over 10 years
• Dwellings built to Part L 2010 - this represents a cost of approx. £600 per dwelling
References
• Carbon Compliance: Setting limits for Zero Carbon – Zero Carbon Hub
• Defining A Fabric Energy Efficiency for Zero Carbon Homes – Zero Carbon Hub
• Allowable Solutions for tomorrows New Homes – Zero Carbon Hub
• SAP 2012 in a Nutshell – National Energy Services