Transcript Building Regulations

NBS-M009
2010
LOW CARBON BUSINESS REGULATION
AND ENTREPRENEURSHIP
Control of Energy use in Buildings
Building Regulations
Recipient of James Watt Gold Medal
N.K. Tovey (杜伟贤) M.A, PhD, CEng, MICE, CEnv
Н.К.Тови М.А., д-р технических наук
1
Lecture 1
Lecture 2
1
11
Building Regulations
• Review of Building Regulations in UK
– Factors affecting energy consumption and carbon
emissions
– Standard Assessment Procedure
• Code for Sustainable Homes
• Energy Performance Certificates
• Introduction in Indian Building Regulations
• Introduction to Chinese Building Regulations
Lecture 1
Lecture 2
Lecture 3
2
Introduction of Building Regulations
• Until 1965 there were no national Building Codes.
• Previously Local Bye Laws prevailed and modes of construction varied
from one part of UK to another.
• First Building Regulations did not include requirements for Energy
Conservation – these came in 1976
• Building Regulations are divided into sections and associated Approved
Documents (ADs)
•
Part A: Structural Maters
•
Part B: Fire
•
Part F: Ventilation
•
Part H: Heat producing appliances
•
Part L: Energy Conservation and more recently carbon emissions
• Each Part has associated Ads e.g. for Part L the Approved Documents
were originally ADL.
• Subsequently divided into ADL1 and ADL2 covering dwellings and nondwelling separately
• Then subdivided further into ADL1a and ADL1b covering new and
existing buildings.
3
Changes in the Heating Standards of Houses
• First introduced as Part L in 1976
• Basic Statement – largely following what was then
common practice
e.g. cavity walls brick cavity block with no
insulation: - no insulation in floor, minimal
insulation in loft.
• 1994: First attempt to address overall annual energy
consumption, although elemental method of
compliance was still permitted
• 2002: Carbon Index introduced
• 2006: Target Emission Rate and Dwelling Emission
Rate introduced.
• 2010: Came into force Oct 1st 2010 – relatively
minor updates on 2006 Regulations
4
Many Deficiencies in earlier Building Regulations
• Before 1994 if double glazing was used
– window area could be doubled
– requirements for walls/roof/floor could be relaxed
if overall loss < = standard house (type 1 trade off)
• From 1995
– Could include incidental gains from appliance use/solar gains
– If consumption <= standard house - regulations could be relaxed
further
• 1994 & 2000 regulations
– If triple glazing used window area can be increased by 50% (type 2
trade off)
– If higher insulations for walls used, greater window area permitted
provided <= standard house.
• Traditionally framed for minimum compliance rather than
actively promoting energy conservation
– Less an issue in 2000 Regs
– 2005 Regs tightened further reducing opportunities for trade-offs
On other hand some of these trade-offs potentially could encourage innovation?
5
U-Value Specification with different Regulations
1976
1985 1990
1994
2000
2005
2010
U – Values W m-2 oC-1
SAP SAP >
< 60
60
External Wall
1.0
0.6
0.45
0.45
0.35
0.45
0.35
0.35
Roof
0.6
0.35
0.25
0.2
0.16
0.25
0.16
0.16
Floor
1.0
0.6
0.45
0.35
0.25
0.45
0.25
0.25
3.0
2.0*
3.3
2.0
2.0
25%
25%
Windows
Not specified
Windows as %
of external
walls
17%
12%
Windows as %
of total floor
areas
-
-
-
15% 22.5% 25% 22.5%
6
Comparison of energy consumption for a standard detached
house at various ages and improvements (Heat losses in W0C-1)
800
700
unimproved
600
25mm
500
50mm
400
100mm
300
100+CAV
200
100+DG
100
100+DG+CAV
150+DG
0
pre- post- 1960s 1976 1985 1990 1994 2000
war war
DG – double glazing
CAV – cavity wall insulation
Numerical value indicates thickness of loft insulation
200+DG+CAV
250+DG+CAV
7
0
Bungalows
centre
mid-storey
top centre
bottom centre
mid-storey end
top end
bottom end
Houses
semi-detached
600
detached
terraced
500
semi-detached
detached
Effects of built form on energy consumption (Heat loss
WoC-1)
2002
1976
Flats
400
300
200
100
8
Compliance to Building Regulations
• Compliance to Building Regulations may be achieved by
one of several alternative methods.
– Elemental Method
• Specifies maximum U-value and perhaps maximum
glazed area – valid until 2002 Regs
– Target U-value – weighted average U-value allowed
some flexibility in design
– SAP Rating (1994 Regs) – economic assessment
– Carbon Index (2002 Regs)
– Target Emission Rate (Current Regs)
9
1994 Regulations: A step change
• Single glazing could no longer be used routinely for
domestic buildings
• Glazed area 22.5% of floor area
– 50% greater than 1990 regs
– 50% potential saving lost
• Standard Assessment Procedure
(SAP) rating for new buildings
–
–
–
–
–
0-100 – higher the better
No target SAP but requirements relaxed if >60
SAP 80-84 – Regs automatically satisfied
Includes energy running costs in calculation
Trade offs permitted
• Does not specify ventilation rates but gives method for
estimating
• Make allowance for solar water heating if fitted
• Include hot water requirements
10
Building Regulations 2000
• Implemented April 2002
• Energy rating method
– SAP replaced by Carbon Index method for compliance
– SAP ratings still to be calculated and notified to building control
bodies
• Requirement of heating & hot water changed to encompass
overall system performance, not just controls
– Boiler seasonal efficiency, inspection & commissioning included
• New requirements for efficient lighting systems & provision of
information for householders
• Standards of fabric insulation improved
– Lower (better) standards (loft insulation)
– Reductions in U values (towards technical limits)
– Changed methods for calculating U values
• Lower U values for windows
– Based on sealed double-glazed units with low emissivity panes
– Area of glazing increased to 25% floor area
• Target U-value method retained but provisions for trade-offs
improved.
11
Compliance procedures 2000 Regulations
Three methods to demonstrate compliance with Building
Regulations:
1. Elemental approach
2. Target U-Value method
3. Carbon Index
•
1. Elemental approach – valid if specific conditions are
met.
–
–
–
–
Heating must be gas, oil, heat pump, CHP DH, biogas or biomass
U-values <= Building Regs 2000 standards
Area window, doors, roof lights <=25% floor area
Boiler: SEDBUK efficiency >=78% gas, 80% LPG, 85% oil
see www.sedbuk.com
[SEDBUK – Seasonal efficiency of domestic boilers in the UK.
The average annual efficiency achieved in typical domestic conditions.]
12
EU Energy Performance of Buildings Directive
(EPBD) 2002/91/EC
• Aims at improving energy efficiency, carbon emissions
from buildings could be reduced by 22%.
Objectives of the Directive:
• To promote the improvement of the energy performance of buildings
within the EU through cost effective measures;
• To promote the convergence of building standards towards those of
Member States which already have ambitious levels.
Measures include:
•
•
•
•
Methodology for calculating the energy performance of buildings;
Application of performance standards on new and existing buildings;
Certification schemes for all buildings;
Regular inspection and assessment of boilers/heating and cooling
installations.
13
UK Response
Part L Building Regulations (2005)
Approved Document ADL1a
• Came into force in England and Wales on 6 April 2006
(Scotland & Ireland to follow)
• Office of the Deputy Prime Minister (ODPM) now
Department of Local Government and Communities
(DCLG)
• Complies with EU legislation
• Moves away from energy conservation to carbon emission
reduction
• UK National Calculation Methodology (NCM) for energy
performance of buildings based on SAP 2005
14
2. Target U-Value method
• Calculate Target U-Value
– a function of areas of floor, roof, walls, windows etc
• Modify target
– gas & oil boilers: actual SEDBUK efficiency
standard SEDBUK efficiency
– electric & coal heating: divide by 1.15
– No modification for heat pumps, biomass, biogas, CHP
– Purpose of modifications is to give more freedom for
designs using efficient oil or gas boilers
• Modify target if area south facing windows > area
north facing windows
• Calculate weighted average U-value of all external
surfaces
• Weighted average U-value must be <= Target value
15
3. Carbon Index Method
•
•
•
•
•
Most complex method
Replaces SAP energy rating as a method of compliance
Carbon index appears to be 0-10
Must be >= 8 to comply
Max carbon index 10 – but actually 17.7!
– Reality: 8 out of 17.7 or 4.5 out of 10!
• SAP procedure is followed
– up to point of introducing costs of fuels
– actual annual energy consumption is used to calculate the
annual carbon dioxide emission
– translated into a carbon index
16
Standard Assessment Procedure (2001)
• Calculate U-values
• Check U-values are achieved
• Calculate
–
–
–
–
–
–
–
gross heat requirements (Heat Loss Rate)
hot water requirements
incidental & solar gains
effective gains
effective internal temperature
corrected degree-day parameter
net space heating total energy requirement
• Select heating method (pumps, appliance efficiency)
• Calculate Total Energy Requirement
• Estimate energy costs of total space heating, hot water &
pumps
• Deflate energy by Energy Cost Factor – 1994:0.96, 2001:1.05
17
Carbon emissions for same house designed to
different standards
Variation of Carbon Emission and Carbon Index with
Building Regulations
70
pre-war
60
1955
1965
50
2
kg CO2/m /yr
Theorectical
Perfection
in 2002
Regulations
40
1976
30
1985
1990
1994
20
2002
10
Elizabeth Fry
ZICER
0
0
1
2
3
4
5
6
7
8
9
10
Carbon Index
18
Variation of Carbon Emission and Carbon Index
problems with current Building Regulations
20
18
The ore cti cal
Pe rfe cti on
i n 2002
Re gul ati ons
16
2002
12
2
kg CO2/m /yr
14
10
8
6
El i z abe th Fry
ZIC ER
4
2
0
7
8
9
10
Carbon Index
19
Building Regulation: Compliance Summary
Up to and including 2000 Regulations
• Elemental Method – specifying U-values of fabric elements
• Target U-Value – allowed some flexibility of design.
• SAP Rating – an economic measure – only permitted for
compliance in 1994 Regs.
2000/2002 Regulations
• Carbon Index Method- a distorted Carbon Measure
2005/6 Regulations
• Dwelling Emission Rating must be better than Target
Emission Rating. Latter is a derivative of the Target UValue Method.
2009/10 Regulations
• Retains DER and TER but expects a 25% improvement on
performance over 2005/6 standards
20
Carbon Index Calculations (2000 and onwards regulations)
• Attempts to assess the true environmental performance of
a building
• Follow Standard Assessment Procedure to calculate Total
Energy Requirement
• Calculate CO2 emissions for building
• Calculate Carbon Factor (CF)
– CF=CO2 (TFA+45) where TFA is total floor space
– Carbon Index (CI) CI=17.7-9.0 log10(CF)
– Complication of scale >10
• 2000regulations indicated that compliance is 11kg CO2 per
m2 – carbon index of 8
• If true scale was used Zicer & Elizabeth Fry would score
13.5 out of 10.
21
Critique of the Standard Assessment Procedure (SAP)
• Energy efficiency index – but gives a rating that is monetary based not energy
based
• Assumes a general heating level in house – two zones (one living area one
other). Does not allow for actual temperature settings.
• Hot water requirements based on floor area formula not occupancy
• Incidental gains based on floor area not occupancy
• Problem: Is this a sensible approach?
– If occupancy changes then Rating would change, but it is difficult to
compare actual readings with predicted.
• Alcantar (2008) found problems with methodology for incidental gains etc
• 2010 Regulations partly address issue with regard to occupancy – e.g.
• if TFA > 13.9:
N = 1 + 1.76 × [1-exp (-0.000349 × (TFA-13.9)² )] + 0.0013 × (TFA-13.9)
if TFA ≤ 13.9: N = 1
• N is the assumed number of occupants, TFA is the total floor area of dwelling.
22
2006 Regulations Dwelling Emission Rate is method of compliance
- essentially the 2010 Regs are similar with only minor variations in
detail
• Criterion 1
• A Dwelling Emission Rating (DER) must be
calculated taking due account of the U-values, the
size, the types of heating etc using the Standard
Assessment Procedure (SAP)
• The DER must be shown to be less than the Target
Emission Rating (TER) which is computed with
the same size of building and U-values meeting
those as specified in the Regulations.
Essentially this is a derivative of the target U – value method
• Details are shown in Section 2.1.11 of handout
23
2006 Regulations Dwelling Emission Rate is method of compliance
- essentially the 2010 Regs are similar with only minor variations in
detail
Criterion 2 – limits on design flexibility
• Performance of the building must not be worse
than a given standard.
• gives considerable latitude in design – the old
trade-off problem.
• However criterion attempts to limit this type of
trade-off –
see pages 5 and 6 of the Approved Document
Criterion 3 – Limiting effects of solar overheating
• Requires that the effects of overheating in summer
must be addressed
24
2006 Regulations Dwelling Emission Rate is method of compliance
- essentially the 2010 Regs are similar with only minor variations in
detail
Criterion 4 Quality of Construction
• Criterion requires evidence of actual performance
– e.g. changes arising from design modifications,
quality of workmanship.
Some of the requirements involve pressure testing the
building to ensure they have achieved those used in the
design specification.
Criterion 5. Providing Information
• Requires information on the maintenance and
operation of the building to be made available.
25
Critique of the Standard Assessment Procedure (SAP)
• Standing charge ignored for electricity, included for gas. Oil doesn’t
have a fixed charge
• Can lead to some perverse consequences
– Lower efficiency oil heating can give a higher SAP rating than more
efficient gas
• Energy Cost Deflator is needed
– Unnecessary complication that allows for inflation
– But does not allow for differential prices changes between fuels
• SAP 1995 – possible SAP rating of over 110
– SAP of 100 readily achievable
• SAP 2001 – widened scale (over 120) for consistency with existing
scale
• SAP 2005 changed scale to have 100 for zero energy house – means
all previous calculation have to be redone.
– Now possible to get > 100 if a house is carbon negative – i.e. will be
exporting more energy than it consumes.
26
CALCULATION of SAP RATING
• While the Standard Assessment Procedure makes sense the
final Rating known as the SAP Rating creates problems
• The SAP rating is related to the total energy cost by the
equations:
• Energy Cost Factor (ECF)
= deflator × total energy cost / (TFA + 45) (10)
• The total energy running cost includes not only heating but
also requirements for hot water, lighting etc as well as
pumps/fans associated with heating. These are
proscribed costs according to a table which are not actual
costs.
• The deflator is a factor which varies according to energy
costs and is intended to keep SAP Ratings constant with
time irrespective of changes in fuel prices - this has not
been the case in the past.
CALCULATION of SAP RATING 2010
• First work out the Energy Cost Factor (ECF)
• where
ECF = deflator × total energy cost / (TFA + 45)
and TFA is the total floor area of the dwelling.
[the energy cost factor initially has been set at 0.47]
• if ECF >= 3.5,
SAP 2009 = 117 – 121 x log10(ECF)
• if ECF < 3.5,
SAP 2009 = 100 – 13.95 x ECF
Note (q) on page 151 of the SAP document indicates
deflator will change to keep SAP Rating constant overall
but that for individual fuels the Rating will vary.
Impact of Changing Methodology on SAP Rating
2005
SAP
1
10
20
30
40
50
60
70
80
90
100
Mains
gas
1
9
19
29
39
48
58
67
76
85
94
LPG
10
20
31
41
50
59
68
76
84
92
99
SAP Rating 2009
Oil
Electricity
1
9
19
29
39
50
60
70
80
90
100
6
16
26
37
46
56
65
74
82
91
99
Solid
mineral
12
21
31
41
50
59
68
77
85
93
100
Biomass
9
18
28
37
47
56
65
74
83
92
100
These changes are relatively small compared with changes in previous
methodology changes – i.e. 1995 – 2001 and 2001 – 2006.
However these demonstrate the problem of using Economic Cost as a Key
Factor in determining the SAP Rating
Climatic Issue with 2010 Calculations
Calculations have to take account of
Climate Variations of Solar Gain for
Assessment of Cooling Requirements
But NOT Heating (even though
heating requirements will vary by up to +/25% from one part of country to another
Benefit of Solar Panels does not account
for geographic variations in solar radiation
even though this information is available
for coolign calculations.
30
Effective changes in SAP 1995 rating with specific
changes
SAP changes by:
Change U-values by 10%
2–3
Change window area by 10%
1–2
Change floor area by 10%
4–5
Change heating from mains
gas to LPG (little change in
energy consumption)
- 15
Change heating from
condensing gas to inferior oil
+5-10 !!!!!
Sources: Monahan, J (2002) MSc Dissertation UEA;
Turner, C. (2003) BSc Dissertation UEA
31
Improvements for 2010 - Environmental Impact Rating (EI)
Calculating the TER
• TER2010 = (Ch x FF x EFAh + Cl xEFAl) x (1–0.2)* (1 – 0.25)
25% improvement on 2005
• Where
Ch is the energy requirements for space heating and hot
water including any used in circulating pumps,
Cl is the energy use for lighting
FF is a fuel factor
EFA is the relevant Emission Factor Adjustment and is a ratio of the
emission factors used in the 2009 calculations divided by the
equivalent ones in the 2005 calculations.
Improvements for 2010 - Environmental Impact Rating (EI)
• Carbon Factor (CF) = (CO2 emissions) / (TFA + 45)
where TFA is the Total Floor Area
• if CF >= 28.3
EI rating = 200 – 95 x log10(CF)
• if CF < 28.3
EI rating = 100 – 1.34 x CF
where the CO2 emissions are calculated according to the
Standard Assessment Procedure
•
•
•
•
•
The EI rating is essentially independent of floor area
It will vary slightly depending on actual plan shape
A house with zero emissions will have the EI at 100
An EI > 100 if a house is a net exporter of energy.
Primary energy requirements are also calculated in a
similar way to CO2 emissions.
Improvements for 2010 - Environmental Impact Rating (EI)
• Letter Rating bands are assigned as follows
It applies to both the SAP rating and the
Environmental Impact rating (why the SAP Rating??).
Rating Band
EI Range
> 92
Letter Rating
A
81 to 91
69 to 80
55 to 68
39 to 54
B
C
D
E
21 to 38
1 to 20
F
G
How has the performance of a typical house changed
over the years?
Original Construction
•
•
•
•
Brick – brick cavity
walls
Metal windows
Solid floor no
insulation
No loft insulation
Bungalow in South West Norwich built in mid 1950s
35
Changing Energy Requirements of House
Annual Energy Consumption
30000
25000
kWh
20000
15000
House constructed
in mid 1950s
First attempt to address overall
consumption. SAP introduced.
Part L first
introduced
~>50% reduction
10000
5000
0
Inter post- 1960s 1976 1985 1990 1994 2002 2006
war war
In all years dimensions of house remain same – just insulation standards change
As houses have long replacement times, legacy of former regulations will affect
ability to reduce carbon emissions in future
36
Changing Energy Requirements of House
Annual Energy Consumption
30000
25000
kWh
20000
15000
House constructed
in mid 1950s
As Existing but
with oil boiler
Existing house –
current standard:
gas boiler
10000
5000
0
Inter post- 1960s 1976 1985 1990 1994 2002 2006 gas
war war
oil SAP
2005
Improvements to existing properties are limited because of in built
structural issues – e.g. No floor insulation in example shown.
House designed to conform the Target Emission Rate (TER) as specified
in Building Regulations 2006 and SAP 2005.
37
Issue of Fuel Choice for carbon reduction
Example:
Heat house with condensing gas boiler ~ 90% efficient
For each unit (kWh) of heat provided.
– 1/0.9 = 1.11 units of gas must be supplied
– Carbon associated with this ~ 0.21 kg
– Direct electric heating
~ 0.52 kg
•Heat Pump with Coefficient of Performance of 4
– Carbon emission associated = 0.52/4 = 0.13
– A 38% saving over gas.
– Note some people claim higher savings based on
incorrect DEFRA carbon factor of 0.43
– Improved performance of heat pumps is possible
with under floor heating
38
Changing Carbon Dioxide Emissions
CO2 emissions (kg)
9000
8000
7000
6000
5000
Annual CO2 Emissions
House constructed
in mid 1950s
As Existing but
with oil boiler
Existing house –
current standard:
gas boiler
4000
3000
2000
1000
0
Inter post- 1960s 1976 1985 1990 1994 2002 2006 gas
war war
oil SAP
2005
Notice significant difference between using gas and oil boiler.
House designed to conform the Target Emission Rate (TER) as specified
in Building Regulations 2006 and SAP 2005.
39
Code for Sustainable Homes
Responding to the Challenge
Recipient of James Watt Gold Medal
N.K. Tovey (杜伟贤) M.A, PhD, CEng, MICE, CEnv
Н.К.Тови М.А., д-р технических наук
Energy Science Director CRed Project
40
HSBC Director of Low Carbon Innovation
40
The Future: Code for Sustainable Homes
• Introduced over next few years to improve
standards to ultimate “zero carbon house”
• But objectives of a low carbon future may be
jeopardised if attention is not also paid to
sustainable transport associated with new
dwellings
16000
14000
Lighting
12000
Refrigeration
10000
Entertainment
Miscellaneous
8000
Air/Public Travel
6000
Data for 1 household with 2 cars
Washing/Drying
4000
Private Car
2000
Heating
0
1
41
The Code For Sustainable Homes
The Code for Sustainable Homes is a set of sustainable design
principles covering performance in nine key areas.
1. Energy and CO2
9 key areas of performance….
2. Water
3. Materials
4. Surface water run-off
5. Waste
6. Pollution
7. Heath and well being
8. Management
9. Ecology
http://www2.env.uea.ac.uk/cred/harrisongroup/Code_for_Sustainable_Homes.htm
42
Code for Sustainable Homes: Certificates
Code
Assessed.
This house
gets 5*
Non
Assessed
Code is voluntary at present, but a NIL Certificate is
needed if assessment is not done
43
Code for Sustainable Homes: Certificates
44
Relative Weighting of different Code categories
Total Credits available, Weighting Factors and Points
Categor ies of Environmental
Impact
Category 1: Energy and CO2
Emissions
Category 2: Water
Category 3: Materials
Category 4: Surface Water Run-off
Category 5: Waste
Category 6: Pollution
Category 7: Health and Wellbeing
Category 8: Management
Category 9: Ecology
Total
Total
credits in
each
category
Weighting
factor (%
points
contribution)
Approximate
weighted
value of each
credit
29
36.4%
1.26
6
24
4
7
4
12
9
9
–
9.0%
7.2%
2.2%
6.4%
2.8%
14.0%
10.0%
12.0%
100.0%
1.50
0.30
0.55
0.91
0.70
1.17
1.11
1.33
–
45
Minimum Standards for Energy and Water
Energy
Water
Code Level
Standard (%
better than
ADL1a)
Points
Awarded
Standard
(litres /
person / day)
Points
Awarded
Other Points
Required
Level 1 *
10
1.2
120
1.5
33.3
Level 2 **
18
3.5
120
1.5
43.0
Level 3 ***
25
5.8
105
4.5
46.7
Level 4
****
Level 5
*****
44
9.4
105
4.5
54.1
100
16.4
80
7.5
60.1
Zero
Carbon
17.6
80
7.5
64.9
Level 6
******
46
Credits gained for different improvements
Dwelling Emission Rate DER (Maximum 15 credits)
% Improvement of DER over
TER
Credits
Mandatory Levels
≥10%
1
Level 1
≥14%
2
≥18%
3
≥22%
4
≥25%
5
≥31%
6
≥37%
7
≥44%
8
≥52%
9
≥60%
10
≥69%
11
≥79%
12
≥89%
13
≥100%
14
Level 5
True Zero Carbon
15
Level 6
Level 2
Level 3
Level 4
47
Roadmap to 2016
Date
2013
2016
25%
44%
Zero
Carbon
Water Efficiency Standard
105l/p/day
105l/p/day
80l/p/day
Equivalent energy/carbon
standard in the Code
Code Level 3
Code Level 4
Code Level 6
Energy/carbon improvement
as compared to ADL1a
(Building Regulations 2006)
2010
Major progressive tightening of the minimum energy
performance standards in building regulations - by
• 25 % in 2010,
• 44 % in 2013 –
• up to the zero carbon target in 2016.
48
What Does Zero Carbon Mean?
• Where the net carbon emissions from all energy
used in the dwelling are zero or better.
• Where the heat Loss Parameter is 0.08 W/m2K –
an indicator of exemplar building fabric
• Off site energy must be private wire –connected to
the site
• Using a “Green” Tariff cannot be used to reduce
carbon
• Nor can purchase of offsets
49
Implications of Code on Carbon Dioxide Emissions
8000
CO2 emissions (kg)
7000
House constructed
in mid 1950s
6000
5000
4000
3000
2000
1000
-10%
-18%
-25%
-44%
0
As
current SAP Code 1 Code 2 Code 3 Code 4 Code 5 Code 6
constructed
reference
Code 5: Zero Carbon House for Heating/Hot Water and Lighting
Code 6: Zero Carbon House overall
but in reality is this achievable?
50
Responding to the Challenge:
Improvements on the SAP 2005 standards as required
by the different code levels can be met by:
• Improved Fabric performance
• Lower U-values
• Technical Solutions
•
•
•
•
•
•
Solar Thermal
Solar Photo-voltaic
Heat Pumps
Biomass
Micro- CHP
Low Energy Lighting (SAP 2005 already specifies 30%)
• Energy Service Companies may offer a solution for financing
• Issues of Carbon Trading
51
Responding to the Challenge: Technical Solutions
What can be achieved through
• Improved Fabric / standard appliance Performance
• Using SAP 2005 standard reference
• Explore different combinations of following
improvements.
Item
SAP
Improved
Improved
reference
Value 1
Value 2
Windows
Walls
U-value = 2
U-value = 0.35
Floor
Roof
U-value = 0.25
U-value = 0.16
Boiler
efficiency
78%
U-value = 1.4
U-value = 0.25
83% default
U-value = 0.1
90% SEDBUK
52
SEDBUK DataBase
(Seasonal Efficiency of Domestic Boilers in UK)
WEB PAGE: www.sedbuk.com/index.htm
53
The Future: Code for Sustainable Homes
3000
CO2 emissions (kg)
Improvements in Insulation
and boiler performance
Annual CO2 Emissions
2500
Code 1
2000
Code 2
1500
1000
500
0
A
B
C
D
E
Option
A SAP Reference
B Boiler η = 83% (default)
C Boiler η = 90% (SEDBUK)
D η = 90%: Walls: U = 0.25
E η = 90%: Walls: U = 0.10
F η = 90%: Windows: U = 1.4
G C+D+F
H C+E+F
F
G
H
Option H nearly
makes code 3
SAP 2005 standard
Walls:
0.35 Wm-2oC-1
Windows: 2.0 Wm-2oC-1
Boiler η
78%
CO2 Emissions (kg) Reduction
2504
0
2377
5%
2229
11%
2150
14%
2034
19%
2112
16%
2033
19%
1919
23%
Credits
0
0
1
2
3
2
3
4
54
Responding to the Challenge: Technical Solutions
What can be achieved through
• Use of Domestic Solar Energy
• Different solar thermal collector areas
• Different combinations of storage tank
• Use of PV
• Use of combinations of solar thermal with PV
55
Responding to the Challenge: Technical Solutions
Solar Thermal Energy
Basic System relying solely on solar energy
56
Responding to the Challenge: Technical Solutions
Solar Thermal Energy
indirect solar cylinder
Solar tank with combi
boiler
57
Responding to the Challenge: Technical Solutions
Solar Thermal Energy
Solar
Pump
Normal hot water
circuit
Solar
Circuit
Dual circuit solar cylinder
58
Responding to the Challenge: Technical Solutions
Solar Thermal Energy
Solar Collectors installed
27th January 2004
Annual Solar Gain 910 kWh
59
Responding to the Challenge: Technical Solutions
Solar Thermal Energy
Solar Gain (kWh/day)
9
December
February
April
June
August
October
December
7
6
5
4
3
2
Solar Hot Water performance
6
1
5
0
kWh per day
Solar Gain (kWh)
8
January
March
May
July
September
November
4
2006-07
2007-08
10 20 30 9 19 29 8 18 28 10 20 30 9 19 29 9 19 29 8 18 28 8 18 28 7 17 27 6 16 26 6 16 26 5 15 25 5 15 1 11 21 31 10
3
2
Day of Month
1
0
60
The Future: Code for Sustainable Homes
Annual CO2 Emissions
3000
CO2 emissions (kg)
Improvements using
solar thermal energy.
How far can things be
improved?
2500
2000
Code 1
1500
Code 2
1000
500
0
A
A
B
C
D
E
F
G
B
C
D
E
F
G
SAP Reference
Boiler η = 90% (SEDBUK)
η = 90%: Solar Thermal – 2 panels dual cylinder
η = 90%: Solar Thermal – 2 panels separate cylinder
η = 90%: Solar Thermal – 3 panels separate cylinder
η = 90%: Solar Thermal – 4 panels separate cylinder
η = 90%: Solar Thermal – 5 panels separate cylinder
Note: little extra benefit
after 3 panels, but does
depend on size of house
CO2 (kg) Reduction Credits
2504
0
0
2229
11%
1
2061
18%
3
2027
19%
3
1991
20%
3
1969
21%
3
1953
22%
4
61
S
Responding
to the Challenge: Technical Solutions
Solar PhotoVoltaic
62
The Future: Code for Sustainable Homes
3000
CO2 emissions (kg)
Improvements using
solar Photovoltaic
Annual CO2 Emissions
2500
Code 1
2000
Code 2
1500
Code 3
1000
Note: 2 panels of solar
thermal have same
benefit as 5 sqm of PV
500
0
A
A
B
C
D
E
F
B
C
D
E
F
CO2 (kg) Reduction Credits
SAP Reference
2504
0
0
Boiler η = 90% (SEDBUK)
2229
11%
1
η = 90%: Solar PV 5 sqm
2052
18%
3
η = 90%: Solar PV 10 sqm
1874
25%
5
η = 90%: Solar PV 5 sqm + 2 panel solar thermal
1883
25%
5
η = 90%: Solar PV 7.4 sqm + 2 panel solar thermal
1798
28%
5
63
Responding to the Challenge: Technical Solutions
What can be achieved through
• Use of Heat Pumps
• Biomass Boilers
• Will Code 5 be achievable?
64
Responding to the Challenge: Technical Solutions
The Heat Pump
Any low grade source of heat may be used
• Coils buried in garden 1 – 1.5 m deep
• Bore holes
• Lakes/Rivers are ideal
• Air can be used but is not as good
• Best performance is achieved if the temperature
source between outside source and inside sink is
as small as possible.
Under floor heating should always be considered when installing
heat pumps in for new build houses – operating temperature is much
lower than radiators.
Attention must be paid to provision of hot water - performance
degrades when heating hot water to 55 – 60oC
Consider boost using off peak electricity, or occasional “Hot Days”
65
The Future: Code for Sustainable Homes
3000
CO2 emissions (kg)
Improvements using
Heat Pumps
Annual CO2 Emissions
2500
Code 3
2000
Code 1
Code 4
1500
Code 2
1000
Code 3
500
0
A
A
B
C
D
E
F
G
H
B
C
D
E
F
G
H
CO2 (kg) Reduction Credits
SAP Reference
2504
0
0
Boiler η = 90% (SEDBUK)
2229
11%
1
Ground to Water Heat Pump (Radiators)
1661
34%
6
Air to Water Heat Pump (Radiators)
1962
22%
4
Ground to Air Heat Pump
1606
36%
6
Air to Air Heat Pump
1907
24%
4
Ground to Water Heat Pump (Under floor) 1553
38%
7
Air to Water Heat Pump (Under floor)
1830
27%
5
66
The Future: Code for Sustainable Homes
3000
CO2 emissions (kg)
Various Combinations
Annual CO2 Emissions
2500
Code 1
2000
Code 2
Code 4
1500
Code 3
1000
Code 4
500
0
A
A
B
C
D
E
F
G
H
B
C
D
E
F
G
SAP Reference
Boiler η = 90% (SEDBUK)
Water to Air Heat Pump (under floor)
As C with improved insulation
As D with 100% Low Energy Lighting
As E with Solar Thermal
As E with 5 m2 Solar PV
As E with 10 m2 Solar PV
H
CO2 (kg)
2504
2229
1553
1327
1219
1124
1042
864
Reduction
0%
11%
38%
47%
51%
55%
58%
65%
Credits
0
1
7
8
8
9
9
10
67
The Future: Code for Sustainable Buildings
Annual CO2 Emissions
CO2 emissions (kg)
3000
Improvements using
Biomass options
2500
Code 1
2000
Code 2
Code 4
1500
Code 3
1000
Code 4
500
Note: Biomass with solar
thermal are incompatible
options
0
A
A
B
C
D
E
F
B
C
D
E
SAP Reference
Boiler η = 90% (SEDBUK)
Biomass Boiler
Biomass Boiler with Solar Thermal
Biomass Boiler with 5m Photovoltaic
Biomass Boiler with 10m Photovoltaic
Biomass Boiler + 10m PV + improved
G insulation + 100% Low Energy lighting
F
G
CO2 (kg)
2504
2229
673
670
496
318
147
Reduction Credits
0%
0
11%
1
73%
11
73%
11
80%
12
87%
12
94%
13
68
Ways to Respond to the Challenge: Technical Solutions
• Micro CHP plant for homes are being trialled.
• Replace the normal boiler
• But there is a problem in summer as there is limited demand for
heat – electrical generation will be limited.
• Backup generation is still needed unless integrated with solar
photovoltaic?
• In community schemes explore opportunity for multiple unit
provision of hot water in summer, but only single unit in winter.
Micro CHP
69
Responding to the Challenge:
•
•
•
•
•
•
•
•
How can low carbon homes be provided at an affordable cost?
Energy Service Companies (ESCos)
Home costs same initial cost as traditional home
Any additional costs for providing renewable energy, better
insulation/controls are financed by ESCo
Client pays ESCo for energy used at rate they would have
done had the house been built to basic 2005 standards
ESCo pays utility company at actual energy cost (because
energy consumption is less)
Difference in payments services ESCo investment
When extra capital cost is paid off
• Client sees reduced energy bills
• ESCO has made its money
• Developer has not had to charge any more for property
• The Environment wins
70
The Future: Code for Sustainable Buildings: Conclusions
Significant Improvements can be achieved through
• Better Insulation Standards
• Heat Pumps
• Biomass Boilers - but is fuel source sustainable?
• Solar Thermal
• Solar PV
But avoid incompatible options
• Too large a Solar thermal Array
• Biomass with solar thermal
• CHP with Solar Thermal
Will it be realistically possible to achieve code level 5?
71
The Behavioural Dimension: Are Technical Measures Enough?
• Analysis of 114 houses in Norwich using Gas Heating
• Predicted consumption from SAP was within 1.9% of actual energy
consumption for Space Heating/ Hot Water and Gas Cooking.
• Plot shows variation from predicted for each house
• Little variation with household size
• Consumption varies by up to a factor of 9 for any given household size.
• Education/Awareness is important.
provide INFORMATION PACKS
Are Technical Measures alone going to be sufficient to reduce carbon emissions?
72
The Behavioural Dimension
Electricity Consumption
Average kWh/month
1200
1000
800
600
400
200
0
0
1
2
4
3
No. people
5
6
7
• Household size has little impact on electricity consumption.
• Consumption varies by up to a factor of 9 for any given
household size.
• Allowing for Income still shows a range of 6 or more.
• Education/Awareness is important.
73
CO2/ year
0 - 4 tonnes
Variations in Carbon Emissions in existing houses
Analysis: courtesy of Karla Alcantar
4 - 6 tonnes
6 - 8 tonnes
8 - 10 tonnes
> 10 tonnes
74
The Future: Code for Sustainable Buildings
All non-dwellings must display a
certificate such as shown
• >10000m2 from 6th April 2008
• > 2500m2 from 1st July 2008
• All non-residential buildings >
1000m2 from 1st October 2008.
• Separate assessments for airconditioning plant will be phased
in from 1st January 2009
Elizabeth Fry Building:
Penalised because it does not have
thermostatically controlled radiator
values . There are no radiators!!!!!!
Does not get credit for triple/
quadruple glazing – analysis system
cannot cope!!!!!
75
Indian Building Code
• WEBSITE: http://www.hareda.gov.in/ECBC.pdf
• Also available at UEA at
– http://www2.env.uea.ac.uk/gmmc/energy/NBSM14x/Indian_DRAFTECBC27MARCH2006.pdf
Code was formulated following Energy
Conservation Act of 2001
According to Saurabh Kumar, Secretary of
Ministry of Power (18th April 2007), Code
was to be trialled in demonstration areas
from July 2007
An initial appraisal suggests that code
tends to follow the equivalent of an
Elemental Approach, but with differences
76
Indian Building Code
Unlike UK, elemental
standards vary from region
to region according to
climate.
UK has 18 zones each with
different Degree-Days, but
elemental standards are same
[Technically Scotland could
modify standards in
Scotland]
Two identical houses in UK,
one in South West, the other
in North East Scotland, the
energy consumption for
space heating in latter would
be 47% higher than former
Is it sensible to have different standards in different climate regimes?
77
Indian Building Code
Example of U-values for walls
Based on Table 4.3.2 of ECBC 2006.
Note: The U-value in the UK is
0.35 W/m2 oC-1
Climate Zone
Hospitals, Hotels, Call
Centers (24-Hour)
Maximum U-factor
(W/m2 oC-1)
0.352
Other Building
Types (Daytime)
Maximum U-factor
(W/m2 oC-1)
0.352
Hot and Dry
0.369
0.352
Warm and Humid
0.352
0.352
Moderate
0.431
0.397
Cold
0.369
0.352
Composite
78
Chinese Building Code
China is adopting a similar approach to that suggested for India
79
Chinese Building Code
U-Values (W m-2 oC -1)
Country/District
Beijing (2003)
Walls
Windows
Roof
0.82 – 1.16
3.5
0.6 – 0.8
Beijing (current)
0.6
Shanghai (current)
1.0
Germany
0.5
1.5
0.22
Sweden
0.17
2.5
0.12
UK (2005 Regulations)
0.35
2.0
0.16
Canada
0.36
2.86
0.23 – 0.4
Hokaido, Japan
0.42
2.33
0.23
Zones in USA similar to Beijing
0.32 – 0.45
2.04
0.19
Zones in Russia similar to
Beijing
0.44 – 0.77
2.75
0.33 – 0.57
80
81
A Pathway to a Low Carbon Future
未来的低碳之路
1. 不要浪费能源 Awareness: Information Packs
2. 使用效率高的设备 Technical
Solutions to conserve energy
Low energy lighting/better
insulation etc
3. 使用可再生能源
Renewable Energy
4. 抵消碳排放
Offsetting
82