How do you BIM an existing building?South West BIM Hub
Ben Rouncefield-SwalesURS – Sustainable Design & [email protected] 898548
Rapid Energy Modelling2
• One of the world’s leading engineering, construction and technical services firms.
• Focuses on four key markets:• Infrastructure• Governments• Power• Industrial & Commercial
• Fully integrated services support full project lifecycle.
• Serves federal, national, state and local government agencies, FORTUNE 500 companies and other multinational corporations.
• Approximately 57,000 employees in more than 50 countries worldwide.
URS - Overview
Rapid Energy Modelling
Who cares about existing buildings?
But 70% of all buildings in 2050 are already built
Buildings are responsible for 40% of global energy demand
Rapid Energy Modelling
Carbon Liability: schemes like the CRC require private and public energy users to pay a tax on their energy bill
The EPBD - net-zero energy by 2019 for all new buildings, and carbon neutrality by 2019 for all new commercial buildingsUnable to let E rated buildings from April 2018
Energy costs drive landlords to improve the thermal efficiency of their existing building stock
Research shows higher rental income secured for buildings with sustainability credentials
What are the Drivers for Change?
Rising energy costs will force occupiers to adopt sustainable operations and improve the efficiency of M&E equipment
The Green Deal intended to stimulate the improvement of energy efficiency in existing buildings
Rapid Energy Modelling
What is happening now?
• Traditional energy audits• Cost can vary depending upon level of output required• Some modelling may be done for high investment items – usually at design
stage
• More involved AM&T contracting• High cost and long contract periods• Creates good data but still need to work up into opportunities• Typically outputs are data not models
• Energy Performance Contracting• Investment grade energy audit• Detailed modelling to underpin finance• No initial cost to client but pays through savings
• Do It Yourself• Success varies depending upon in-house skills• Unlikely that any modelling would be done
Rapid Energy Modelling
That’s why URS developed REM
• Rapid Energy Modelling
• A tool developed by URS in partnership with AutoDesk
• Uses innovative means to quickly construct a 3D model of the building
• Physical Audit feeds information into the model
• ReVit models the building and tests improvement measures
• Ouptut leaves a legacy model for the building
MANAGE
BUILD
DESIGN
PLAN
Rapid Energy Modelling
The REM process
Information capture
• Physical audit of building• 3D geometry capture (multiple approaches)
Computer model
• 3D geometry defined• Building characteristics identified: fabric, services and systems• Location, climate and occupancy profiles
Building performance
• Modelling engine produces simulation• Energy required for heating, cooling, lighting, hot water etc.
Improvement simulation
• Model is modified to represent improvements• Results illustrate benefits in energy reduction and emissions
Space heating
1%
Pumps & Aux4%
Fans8%
Space cooling
11%
Exterior loads
1%Misc equipment
35%
Lights40%
Rapid Energy Modelling
Laser scanning
Rapid Energy Modelling
Photogrammetry
Rapid Energy Modelling
3D sketching
Rapid Energy Modelling
• From a floor plan – in 30 minutes
• Generated from 2D plans & elevations using AutoCAD, Revit, Vasari, Google Sketchup etc.
• From the laser scan – in 2 hours
• No drawings required – photogrammetry builds a 3D model
Rapid Response
Rapid Energy Modelling
Immediate decision making
Rapid Energy Modelling
Option & Sensitivity Studies - Readily Undertaken
Alter key building elements and observe impact on energy & CO2 outputs and also quality of internal space
Unimproved
With external shading
Rapid Energy Modelling
Example output - recommendations
1 3 5 4 7 6 2 8 12 13 9 10 17 16 14 19 18 23 21 20 22 24 15-1000
0
1000
2000
3000
4000
5000
6000
0
100
200
300
400
500
600
700
Marginal Abatement Cost Curve
Net Specific Cost £/tCO2
Net
Spe
cific
Cos
t £/tC
O2
Cum
ulat
ive
CO
2 Sa
ving
s
Short Term Medium Term Strategic1 Space set points on heating system 17 Solar Thermal 20 Upgrade lighting to LED 3 Time clock on water heaters 16 Thermal performance – Ext. Walls 22 Draft lobby at main entrance5 Replace boilers 14 Energy heat meters 24 Thermal performance-windows4 Upgrade time clock system 19 Photo Voltaics 15 Slave Terminals7 Daylight dimming system 18 Thermostat & time control 6 Install PIR control 23 Occupancy sensing on cooling 2 Variable Speed Drives 21 Thermal performance - Roof 8 Repair Damaged windows 12 Lighting zoning and control system 13 TRVs 9 Reduce door air leakage 10 Adapt T8 to T5 light fittings
Case Study
18
Rapid Energy Modelling
City of London office - introduction
• Late-Victorian office• Multi-tenanted• Circa 3,500 m2
• 7 stories• Energy spend c. £50k p.a.
Rapid Energy Modelling
City of London office – REM
• Site visit circa 3 hours• Photogrammetry model• Rapid Energy Model created• Accuracy <10% difference
Space Cooling, 5.9%
Space Heating, 7.3%
Fans, 3.5%
Heat Pumps, 11.6%
Exterior loads, 2.0%
Misc equipment,
44.3%
Lights, 25.4%
*includes small power, computers, communications equipment, printers etc
*
Rapid Energy Modelling
City of London office – Improvement Recommendations
Low Cost, Quick Wins Medium Cost Strategic
Energy cost saving (p.a.)
£ 10,260 £ 9,570 £7,550
Carbon emissions saving (p.a.)
21% 19% 15%
Specific improvement measures
Review and implement Good Practice recommendations (behaviour & operation)
Install Voltage Optimisation Unit Upgrade lighting to LED lamps in appropriate areas
Install time clock on water heaters Install lighting PIR occupancy control Install occupancy sensing on cooling systems within meeting rooms
Interconnect existing control systems Install daylight dimming systemInstall thermostat and time control on electric panel heaters within communal parts
Adapt T8s to T5s in main officeReplace laptops / docking stations / terminals with "mainframe" and slave monitor and keyboard terminals
Implement energy metering strategy Replace centralised hot water with point of use hot water supplies
Rapid Energy Modelling
City of London office – Improvement Recommendations
-
50
100
150
200
250
300
350
-
10
20
30
40
50
60
Benchmark Current Building Low Cost Quick Wins
Medium Term Strategic
CO
2(to
nnes
p.a
.)
Ener
gy c
ost (
£k p
.a..)
Energy cost
Carbon
Rapid Energy Modelling
REM experience across the Built Environment
• REM studies undertaken since March 2011
• Accuracy consistently <±10%
• Average CO2 and energy savings identified circa 40% Oxford University
Student Accom.URS Basingstoke
OfficeAB InBev Belgium
OfficeManchester Council
Office (Nat vent)
URS NottinghamOffice and Labs
AB InBev BremenOffice
Oxford UniversityStudent Accom.
Major Property Man.Office (Period)
GatesheadHousing Block
Summary
24
Rapid Energy Modelling
• Lots of buildings – most already built• Poor understanding of building performance • Traditional audit / survey take a long time• Need to act now to meet commercial imperatives:
• Delivering cost savings• Improving energy performance• Enhancing working environment • Reducing carbon emissions
Key issues
Rapid Energy Modelling
What benefits will REM bring?
• It helps reduce a building’s energy running costs and CO2 emissions
• It provides a rapid focus on building improvement options
• It is a Building Information Modelling (BIM) process, creating a legacy model that can be retained and refined
• Improves building user environment