energy & carbon in buildings: are we measuring the right ......natural ventilation air...

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Energy & carbon in buildings:

are we measuring the right things?

David [email protected]

What we do

Building services engineering

Acoustic engineering

Fire engineering

Survey Solutions

Civil engineering Structural engineering Sustainability

Building Information Modelling (BIM)

Geotechnical and geoenvironmental

Transportation

Building automation

ICT and AV

Vertical transportation

CDM coordination

Lighting design

Data Centre Infrastructure Management (DCIM)

Planning

2

Where we are

Benchmarking energy

3

• Energy– Energy Performance Certificate (EPC)

– Display Energy Certificate (DEC)

• Environmental– BREEAM

– BREEAM-in-Use

– LEED

– LEED EBOM

– SKA

– CEEQUAL

Measurement tools in the UK

Which is the lowest carbon building?

A rated EPCAlnwick

BREEAM ExcellentLondon

D rated DECManchester

Don’t know – different benchmarks

4

Based on A/C only – no mixed mode (C rating with)

H 176-200

I 201-225

J 226-250

K 251-275 269

Energy ratings - spot the difference?Computer Model

C / D

Actual Energy

G ++

65% energy reduction required to get 100 points (D rating )

EPC v DEC (virtual v reality)

EPC Ratings

Actual energy consumption

No correlation between EPC and

actual energy consumption

Source: A Tale of Two Buildings, JLL / BBP, 2012

5

• Legislation uses modelled energy– No correlation with metered energy

– Are we trying to save energy on paper or in real life?

• Real energy data required– To turn theory into reality

– To focus on what actually works

– To replicate success

– To avoid repeating mistakes

• Limited data available– DEC database not public

– Private sector rarely publishes data

The need for real data

An ‘A’ rated DEC?

Benchmarking needs to include occupancy

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Will this motivate people to act?

123 office buildings in London

Ratings not adjusted for hours of operation or seperables

Occupancy rates or density not considered

60% get a ‘G’

Source: BBP Draft DEC analysis (2009-10)

no. of buildings532

2,3111,367167266152359

138196455

57,2476,0001,023

1,074

0 20 40 60 80 100 120 140 160

Cundall UK Offices 2010

Natural Ventilation

Air Conditioning

DEC Database 2010

Heating & Natural Ventilation

Mixed Mode & Natural Ventilation

Heating & Mechanical Ventilation

Mixed Mode & Mechanical Ventilation

Air Conditioned

Better Buildings Partnership 2012

Non Air Conditioned

Air Conditioned ‐ Standard

Air Conditioned ‐ Prestige

Energy Star Portfolio Manager 2012

US Commercial Building Survey 2003

New York Offices 2011

Greenprint Index 2011

kgCO2e/m2 of GIA

100kgCO2e/m2 of GIA

The DEC scale needs fixing

Source: What Colour Is Your Building, David Clark, RIBA Publishing 2013

D rated DEC

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Performance of green buildings


0 20 40 60 80 100 120 140 160 180 200 220

Beaufort Court, Kings Langley

Pool Innovation Centre, Pool

Powys County Council Learning Centre, Powys

60L Green Building, Melbourne

Wessex Water, Bath

Lion House (ZEBRA), Alnwick

BRE Environment Building, Garston

Elizabeth II court, Winchester

Eden Foundation, St Austel

Woodland Trust, Grantham

South Cambridge District Offices, Cambourne

Environment Agency, Wallingford

Commerzbank HQ, Frankfurt

Heelis, NT HQ, Swindon

Mid Beds Council Offices, Shefford

Centre for Mathematical Sciences, Cambridge

Arup Campus, Solihull

Barclaycard HQ, London

Eland House, London

St Pauls Place, Sheffield

7 More London *

50 Queen Annes Gate, London

One First Street, Manchester

Vulcan House, Sheffield

201 Bishopsgate, London

DEC rating scale

kgCO2e per m2 of GIA

Electricity Nat Gas Electricity offset by renewables Nat Gas offset by renewables

100kgCO2e/m2

of GIA

Nat

Vent / Mixed M

ode

A/C

A B C D E F G

* ‐ nat gas total includes biofuel used in CHP

A to G scale is not cast in stone

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A fairer rating scale for DECs?

25

50

75

100

125

150

175

A+

A

B+

B

C+

C

D+

D

E+

E

F+

F

G+

G

H > 175

100 would be typical

+ ratings added to upper end

Range at lower end extended to H (175) and + ratings added

• Energy Performance Certificate– Minimum E rating for landlords from 2018

– Used in Green Deal

• Display Energy Certificate– Mandatory for public buildings

– Government reneged on promise to roll out to private sector in 2012

Energy rating tools

EPC

DEC

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• Started out as– Carbon trading scheme – financial incentive

– Public league table of portfolios – reputational driver

– Bureaucratic – fees for lawyers / financial advisers

• Has become– Carbon tax

– No league table

– Still too much bureaucracy

• Why not?– Mandatory DEC ratings – visible to occupants & in

public database

– Add £12/tCO2 on half hourly meter bills = 0.6p/kWh

CRC-EES

Is energy too cheap to drive change?

60%

64%

13%

19%

15%

10%

10%

6%

0% 20% 40% 60% 80% 100%

UK

LondonRent

Rates

Service Charge

Energy Consumption

Utilities / Standing Charges


Energy costs 5 to 10% of office occupancy cost

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But biggest cost is people

£0

£1,000

£2,000

£3,000

£4,000

£5,000

£6,000

EmployeeCosts

Rent Rates ServiceCharge

EnergyConsumption

Utilities /StandingCharges

Annual cost per m

2of NLA

AssumptionsAverage salary = £43,000Employment cost (training, etc) = 30%Occupancy Density = 1 per 10m2 of NLA

7% 0.6%2% 1%

89%

< 0.5%


Tenants just aren’t interested in energy

“Between 2001 and 2011 not one prospective tenant enquired about the

energy performance of a building before signing a lease, and only a handful asked about energy after the lease was signed.”

Head of lettings, de-brief pending his retirement from amajor quoted property company (>1 million m2)

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• DEC rating in foyer

• DEC database freely available on line

• Landlords to report energy consumption to tenants (with service charge)

• Make it easy to turn stuff off and to see the benefit of doing so

Need to make energy visible

Building renewables in perspective

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PV on London office building

10 storeys, 10,000m2

105kgCO2e/m2 of GIA

466m2 of PV panels

No overshadowing

How much carbon does this save?

4.5kgCO2e/m2 of GIA

4% of carbon

Zero carbon office?

15,000m2 of PV panels = 105kgCO2e/m2

1.5m2 of panel per 1m2 of floor

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Micro Urban Wind Turbines

=

Wind turbines

1% reduction100 year payback

1% reduction300 year payback

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0 0.1 0.2 0.3 0.4 0.5

Natural gas

Diesel / petrol

Biofuel

Recycled cooking oil

kgCO2e / kWh

Not all biofuels are low carbon

Source: “Carbon and Sustainability Reporting Within the Renewable Transport Fuel Obligation: Technical Guidance Part Two - Carbon Reporting – Default Values and Fuel Chains” version 2.1 published in July 2010 by UK Renewable Fuel Agency.

Average biodiesel factor from DEFRA = 0.12

Renewables in green buildings


0 20 40 60 80 100 120 140 160 180 200 220

Beaufort Court, Kings Langley

Pool Innovation Centre, Pool

Powys County Council Learning Centre, Powys

60L Green Building, Melbourne

Wessex Water, Bath

Lion House (ZEBRA), Alnwick

BRE Environment Building, Garston

Elizabeth II court, Winchester

Eden Foundation, St Austel

Woodland Trust, Grantham

South Cambridge District Offices, Cambourne

Environment Agency, Wallingford

Commerzbank HQ, Frankfurt

Heelis, NT HQ, Swindon

Mid Beds Council Offices, Shefford

Centre for Mathematical Sciences, Cambridge

Arup Campus, Solihull

Barclaycard HQ, London

Eland House, London

St Pauls Place, Sheffield

7 More London *

50 Queen Annes Gate, London

One First Street, Manchester

Vulcan House, Sheffield

201 Bishopsgate, London

DEC rating scale

kgCO2e per m2 of GIA

Electricity Nat Gas Electricity offset by renewables Nat Gas offset by renewables

100kgCO2e/m2

of GIA

Nat

Vent / Mixed M

ode

A/C

A B C D E F G

* ‐ nat gas total includes biofuel used in CHP

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Biofuel in buildings v vehicles

10 litres of recycled cooking oil

CHP Truck

23kgCO2eCO2e saving 27kgCO2e

£2.25Extra fuel cost £0

LotsCapital cost Zero

Biofuel works better in transport

Why waste it in buildings?

We can’t have wood chip cars!

Recycled oil = 0.05kgCO2e/kWh70p/litre

1 litre = 10kWh

Whole carbon footprint

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The whole carbon footprint of buildings

Embodied carbon

0

100

200

300

400

500

600

700

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

kgCO2e/m

2of GIA per year

Construction Fitout / Refurb Operating

0

1000

2000

3000

4000

5000

6000

7000

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

kgCO2e/m

2of GIA (cumulative)

Construction Fitout / Refurb Operating Cumultive Footprint

kgCO2e/m2 %Construction 700 12%Fitout & Refurb 450 7%Operating Energy 4900 81%TOTAL 6050


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kgCO2 / person by location

0

500

1000

1500

2000

2500

London City / Town Business Park

kgCO2 / person

Low

Medium

High


67%9%

24%

Operating

Embodied

Transport

Operating: 150kgCO2e/m2/year

Embodied (initial): 700kgCO2e/m2

Embodied (in‐use): 550kgCO2e/m2

Commuting: 800kgCO2e/person/year

60 year periodNo energy supply

decarbonisation included

Typical London air con office


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14%

15%

71% Operating

Embodied

Transport

Operating: 20kgCO2e/m2/year

Embodied (initial): 700kgCO2e/m2

Embodied (in‐use): 550kgCO2e/m2

Commuting: 1500kgCO2e/person/year

60 year periodNo energy supply

decarbonisation included

Nearly zero energy office - rural


0 50 100 150 200 250 300

Hypothetical Examples

Almost zero carbon office in rural location

Low energy building in business park

New air conditioned office in business park

New air conditioned office in Manchester

New air conditioned office in London

New "prestige" office in London

Refurbished office in London

Existing “prestige” office in London

Cundall Offices

Birmingham

Edinburgh

London

Manchester

Newcastle

kgCO2e / m2 of GIA per annum

Operating Embodied (initial) Embodied (fitout/refurb) Transport

Low Typical High

Refurb typical office in central London

Almost zero carbon rural office



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We need to reduce the whole footprint

Its not just about energy

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• Many new schools designed under BSF– High energy consumption

– Issues with noise

– Overheating

– Glare

• Why?– Designed to tick boxes in rating tools

– Standards wrong (e.g. Daylight Factor v Useful Daylight Index)

• Solution– Change the rules

Unintended Consequences

Example - good daylight factor

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• Lots of glass– High solar gain leading to

thermal discomfort

– Glare

• Blinds closed – No daylight anymore

– Lights switched on (energy used & heat generated)

– Blinds block natural ventilation air flows

– Solar gain still enters space

– Overheating & higher energy consumption

but consequences are

Change the rules = better design

North Façade Glazing is 30% of the internal wall

where no external obstructions exist.

The acoustic baffles are located away from the window

openings.

Internal Glazing is 25% of the internal wall façade. This

provides secondary light into the space.

The ground floor opening is 1.2m wide to provide daylight to the

ground floor spaces.

The first floor opening is 1.8m

wide to allow daylight to the lower

floors..

Open / translucent balustrade design is

required to allow light to distribute to

the lower floors.

South façade glazing requires a light shelf or light

redirecting component.

Roof lights are placed over the

corridor openings to maximise the

internal daylight.

Floor to ceiling height is 3m where

no external obstructions exist.

Internal reflections must be 70/50/20 as

a minimum.

Source: EFA Baseline Design, 2012

To be built for < £1,500/m2

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Summary

• Legislation is focused on energy efficiency but consumption is ignored

• Large gap between design and actual energy

• Energy cost is small in offices - need to make energy visible to motivate action

• Whole carbon footprint should be considered in planning future built environment

• Change the rules & ratings to get the desired outcomes

In conclusion

ECO2

Transport

Regulated energy

Operatingenergy


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Integrated future planning?

Electric vehicles only in city centres

Green roofs on buildings

Less noiseLess air pollution

Lower local temperatures

Breathe in the fresh airOpen the windows in buildings

Turn off air con

energy & carbon in buildings: are we measuring the right ......natural ventilation air...

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