What can we learn from the commercial sector and building modelling

Chris Twinn

FRSA HonFRIBA FCIBSE MEI CEng BSc(Hons) Founder & CEO of

Buildings that do not cost the Earth

What can we learn from the commercial sector and

building modelling

Gas

This is how energy efficient the building is.

This is how energy efficient the building is.

Game Boy does not need reality

Ratio between reference model and design model

Fitout assumptions

Maximise daylight

Measured energy data

Maximise daylight

Measured energy data

Step 4 – Daylight Quantity not Quality

Step 5 – Dilute perimeter cooling effects across full floorplate

Extent of AirCon

Your EPC is the ratio

between your reference

model and your design

Step 7 – As a basic gaming principle add more complexity to your reference model as it increases the options for saving

Your EPC is the ratio

between your reference

model and your design

Energy modelling is code compliance – it is not a ‘design tool’

- It is not the expected actual energy use of your building

Rest assured that no one can check the actual completed building against your code compliance modelling

Step 7 – As a basic gaming principle add more complexity to your reference model as it increases the options for saving

Gas

This is how energy efficient the building is.

This is how energy efficient the building is.

Incompatible

with low energy

Innovation

LED Task lighting Wireless interface

Beyond

Low energy

corralled equipment New design rules for pumps,

fans, controls, fitout Daylight Quality

- not Quantity, for window design

Occupant control : productivity Monitoring + targeting Chris Tw in n v 10

Passive cooling & low capacity systems Smaller

infrastructure

Cloud servers Personalised

Innovation benefits: Zero Carbon for less cost than BAU?

可控能源

Regula ted e ner gy

不

可控能源

Unregula

ted

参考：城市精装修三层办公楼 Ref: Urban 3 storey grade ‘A’ office with Cat B fitout

Prelims & BWIC Internal surfaces etc Envelope Structure Misc HVAC Electrical £2200/m2

2010 年符合规范 的建筑 2010 Regs

£2050/m2 Zero Carbon 65kWh/m2 Heating & DHW Plug power Lighting Cooling Fans & pumps Misc other Server AC IT server power 145kWh/m2

2010 年符合规范 的建筑 2010 Regs

现场可再生能源 Renewables kWh/m2

Roof area

PV

Biomass boiler

能耗 _Energy 施工成本 Capital cost

• Feed-in-tariff “电价补贴”

• Design-out external shading

• Simple cladding

• Reduced storey height

• Reduced size central plant

• Omit FCUs & simplified systems

• No dropped ceiling 减

少 成 本 特 色

• Smart IT: tablet & ‘Thin client’

• Mobile & ‘Cloud computing’

• Task lights + fewer fixed lights

• In-slab cooling (& heating)

装 修 特 色

• Added insulation & airtightness

• 30% glazing high performance

• Ready for adding operable windows

• Enhanced ceiling slab finish

建 筑 设 计 特 色

CAMPAIGN FOR A SUSTAINABLE BUILT ENVIRONMENT

BUILDING ZERO CARBON – THE CASE FOR ACTION

Where is Part L :2013 in relation to 2019 zero carbon? The UKGBC Zero Carbon Non-domestic Task Group Developing the definition of zero carbon

Putting a scale of the various steps

A ZERO CARBON ROADMAP

Part L 2010 -9% Part L 2010 -20% to -30%

+ lifts + escalators + door heaters ‘Zero carbon’ = regulated

energy only Part L 2010 -30% to -40%

+ Allowable Solutions ‘Zero carbon’ = regulated

+ unregulated energy ‘Zero carbon’ = regulated

+ unregulated + embodied energy ‘Zero carbon’ = regulated

+ unregulated + embodied energy +…

2013 2016 2019

Zero Carbon Embodied CO2

Increasing industry alignment on methodology and assessment techniques Agreed embodied CO2

standard widely adopted across industry

2028?

2025?

2022?

Performance Gap

Optional enhancement to SBEM to more accurately

predict energy usage Feedback from DECs Predicted actual operational energy use

Futur

e

Zero Carbon (regulated) Zero Carbon (embodied)

Zero Carbon (unregulated) Zero Carbon (whole life)

THE CASE FOR ACTION: RECOMMENDATIONS

1. Government should restate its commitment to Zero Carbon non-domestic buildings for 2019

2. DECC, BIS and CLG to work with industry on ‘roadmap’ to 2019 & beyond

3. The Impact Assessment methodology used by Government should be revised

4. Form a Zero Carbon Non-Domestic Buildings Hub

5. Zero carbon definition similar model to residential sector

6. Regulated energy in 2016 extended to cover more fixed

building services

7. Encouragement to measure and reduce embodied carbon

8. SBEM should be developed for more accurate predictions

of energy use

9. Industry-wide measurement and disclosure of operational

energy use

THE ZERO CARBON DEFINITION

A ‘zero carbon’ non domestic building should:

• Have a high level of

building fabric efficiency

• Incorporate efficient

mechanical systems and cost effective renewable technologies

• Allow for off-site

provision to meet net zero carbon target

Proposals to be tested & developed:

Allowable

Solutions

Carbon Mitigation

Elemental Efficiency

Fabric, envelope, simple M&E systems/components

Part L compliance routes

Simple and small buildings Complex buildings Deemed to satisfy if building

all as Elemental

Single model dynamic simulation

Building Baseline Energy

1. Part L defined fabric & systems min efficiencies

Includes solar, U-values x areas, Plant installed capacity, plant efficiencies, vertical transportation, car parks, fans, pumps, chillers, over-door heaters, etc.

2. Part L defines max kWh/m2_.yr

by building type.

Dynamic simulation route uses standard use profiles & is permitted to relax individual elemental values by 20% (as backstops)

3. Part L 2019: Zero Carbon Regulated Energy

Site practicality and economics define proportion of purchased Allowable

Solutions or on-site renewables using FIT. _Unregulated

energy includes the associated cooling energy (& fans etc) for everything in excess of what is in Building Baseline.

In summary:

• Game Boy rules OK

• Beware of unintended consequences

• Ensure engineering judgement underpins the process

• Real energy use is dependant on a series of different stakeholders

Sustainability is about using less materials to deliver the economic prosperity & social amenity society requires