Modelling systems for large scale implementation Simon Lannon and Enrico Crobu

Welsh School of Architecture Cardiff University

The levels to be considered Urban / regional Neighbourhood Building

Modelling systems at different level

A region may have over 100,000 dwellings Can’t model each one in detail Use archetypes, each dwelling is one of a type Consider that 100 archetypes will cover the majority of the stock At this scale we use simple steady thermal models Monthly time step Monthly average weather data is used

Urban / regional - the approach

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VALIDATION

Results are usually aggregated In this case to LLSOA census area which contains 400 to 1,200 households Compared models to DECC consumption gas data Found the model is reasonable when adjustments have been made to the assumptions Gives confidence that the model will work at this scale

Iorwerth, H. et al. 2013. A sap sensitivity tool and GIS-based urban scale domestic energy use model. Presented at: Building Simulation 2013 (BS2013): 13th International Conference of the International Building Performance Simulation Association, Chambéry, France, 25-28 August 2013.

Urban / regional - comparison to DECC data

May have up to 300 dwellings Can model each one in detail Use archetypes, each dwelling is one of a type At this scale we use dynamic simulation models Hourly time step Hourly weather data is used Based in SketchUp, over 50% use in practices Simple user Interface Existing models and terrain

Neighbourhood - dynamic tool

Waldron, D. et al. 2013. Embodied energy and operational energy: Case studies comparing different urban layouts. Presented at: Building Simulation 2013 (BS2013): 13th International Conference of the International Building Performance Simulation Association, Chambéry, France, 25-28 August 2013

Neighbourhood - dynamic tool

Modelled outputs consider: Overshadowing Solar reflections Terrain Potential Solar energy Embodied energy Operational energy

Neighbourhood- simple tool

Simple model with limited parameters: SAP Sensitivity Tool Concentrates on the most crucial parameters, mostly relating to fabric and systems Simple and functional interface. Building types pre-defined, with the user altering items from a baseline

Neighbourhood - case study

The report provides a guidance of the possible routes towards improving the energy efficiency of the existing housing stock of a renewal area Clustering analysis focused on domestic dwellings has been developed in order to maximise the available data, creating representative groups of the larger area. Initial data has been collected by Warm Wales. Alternative routes and associated costs of achieving lower carbon emissions for the area.

Neighbourhood - case study

Castleland Renewal Area, Barry 1,248 homes mostly pre 1919 568 EPCs analysed Compared the traditional fabric first with systems first approach To retrofit all pre 1919 dwellings in the whole area up to HHSRS; Fabric first approach approximate cost of £5,178,218 Systems first approach approximate cost of £1,337,100

Can model each one in high detail Use monitored data and building drawings At this scale we use dynamic simulation models Hourly time step, including weather data

Building - monitored data

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Parametric testing Perform many simulation runs to create the results Output can be view using simple interfaces

Jones, P. J., et al. 2013. Intensive building energy simulation at early design stage. Presented at: Building Simulation 2013 (BS2013): 13th International Conference of the International Building Performance Simulation Association, Chambéry, France, 25-28 August 2013.

Building - sensitivity tools

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Welsh School of Architecture Cardiff University

Building Scale

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Building Energy Performance European Directive suggests that ENERGY CONSUMPTION is AFFECTED by the way buildings are:

• DESIGNED

• BUILT

• COMMISSIONED

• USED

Controlling these variables though does not guaranty that the buildings will be efficient ones.

DESIGN, CONSTRUCTION, COMMISSION AND USE can only control the quality of materials, design strategies, systems, correct execution of the project, monitoring the use of it etc.

The European Directive can therefore only help to assure that building are capable of USING ENERGY IN AN EFFICIENT WAY.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

OCCUPANTS represents the UNKNOWN FACTOR in the process of estimating buildings performance. People daily patterns of activities within a building varies sometimes randomly and it is impossible to forecast.

REAL BUILDINGS:

Monitoring energy consumed in buildings is the most RELIABLE WAY TO UNDERSTAND BUILDINGS AND TO VERIFY IF THEY OPERATED EFFICIENTLY

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

MODELLING not always results in an accurate representation of the reality.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

The possibility of error in the calculation of the load profile of a building may differ by 30% compared to reality, if the pattern of occupancy is not estimated correctly. There is anyway a tendency to assume or deduce behaviour of the occupants for modelling buildings.

2009

Kathryn B. Janda

Environmental Change Institute, Oxford University, Oxford, UK

BUILDINGS DON’T USE ENERGY: PEOPLE DO

“To fully address the carbon reduction task ahead, […] architects need to develop their professional expertise and seek ways of integrating user involvement in building performance.”

2009 Killip

Diagram: Influences on building energy use

MICRO-GENERATION

PLUG LOAD

OCCUPANT BEHAVIOUR

BUILDING ENVELOPE

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

MONITORING

Can be used to find a relationship between energy consumed in buildings and the following aspects:

• WEATHER DATA

• OCCUPANT BEHAVIOUR

• MICRO – GENERATION

• SYSTEMS PERFORMANCES

• FABRIC PERFORMANCES

BETTER UNDERSTANDING OF BUILDINGS AND THEIR USE

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Typical Grid, Demand = Supply

Dynamic Grid, Demand and Load Transfer

Demand, Supply, Storage

Meeting Supply (!) via Load Transfer, Storage and Building Energy Efficiency

Availability of Renewable Resources vs Energy Demand

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Welsh School of Architecture Cardiff University

Modelling systems for large scale implementation Buildings and urban scale modelling approaches available and developments required to deal with the systems based approach.

Building Scale