Between the Poles

Open standards-based foundation for integrating BIM, geospatial and smart meters for urban energy performance optimization

The European Union has set itself aggressive goals to reduce GHG emissions by 20%, increase renewables share of energy generation to 20%, and to reduce energy consumption by 20% by 2020.  The EU seems to be on track for the first two goals, but the third remains a challenge.  In 2020, the European consumption of energy is projected to be 25 trillion kWh.  By 2040 it is expected to rise to 28 trillion kWh.  In terms of primary energy consumption, buildings represent around 40%.  In 2009, residential buildings consumed 68% of the total final energy use in buildings.  Energy in households is mainly consumed by heating (70%), cooling, hot water, cooking and appliances. Gas is the most common fuel used in buildings.

 

I have blogged about the European SUNSHINE project before.  The SUNSHINE (Smart Urban Services for Higher Energy Efficiency) project is focused on energy efficiency for buildings in an urban environment.  It is a European Commission (EC) funded project that started about a year ago and is intended to continue for 36 months.

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Energy certification of buildings is a key policy instrument for reducing the energy consumption and improving the energy performance of new and existing buildings. It is expected to help increase demand for high performance buildings by improving the energy performance of the building stock in urban centers. SUNSHINE is intended as a step towards toward such a policy and a way to  contribute to improving the energy efficiency of buildings.  SUNSHINE is intended to be accessible to Web and mobile platforms. An interesting aspect of the project is is the development of an extended CityGML model for representing urban structures for energy performance modeling.

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Three use cases are being considered.

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1 Assessment of energy performance

The goal is to supports the automatic large-scale assessment of building energy performance based on publicly available data. The building energy performance models will be used for energy.density mapping ("ECOMaps") .  It is intended that an ADE extension to CityGML for 3D building energy modeling will be developed.

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2 Heating and cooling forecast and alerts

This focuses on existing buildings that have been selected for energy performance improvement.  It relies on localized weather forecasts and other information to forecast heating/cooling requirements to optimize energy performance..

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3 Optimization of power consumption by public lighting

The idea is to control illumination so that areas are only illuminated when people are present and the level of natural lighting requires it.

 

SUNSHINE is based on customizing and integrating other EC-funded smart city applications including

• Smart urban services based on open standards to support energy efficiency of buildings
• Open data hub for data distribution
• eEnvironmental services for advanced applications within INSPIRE
• 3D CityGML models for solar energy potential assessment and noise mapping & simulation

SUNSHINE will be piloted at nine sites across five countries that include 20 public buildings in Ferrara, 60 technical buildings in Trentino, and public illumination systems in several Italian cities.

 

At Geospatial World Forum 2014 in Geneva this year as part of the GeoEnergy track, Piergiorgio Cipriano, GI/SDI Project Manager at Sinergis, Italy discussed integrating energy usage data from smart meters with city models using the CityGML standard with the goal of improving the energy performance of buildings on an urban scale.

Location is essential for linking information from different providers and sources.  The “ecomap” represents the “energy need” at building level.  For this simple map, it is necessary to integrate at the very least the following data in order to predict building energy performance with sufficient precision:

• Building footprints
• Building height (or number of floors)
• Building use(s)
• Building age and corresponding building envelope stereotypes
• Stereotypes for heating/hot-water/ventilation systems

Building modeling for urban energy performance modeling

The fundamental concept is to exploit existing standards as much as possible to avoid reinventing the wheel.  Two relevant standards for the energy performance analysis of buildings are the INSPIRE data specification for the spatial data theme Buildings (INSPIRE-BU) and  Open Geospatial Consortium (OGC) CityGML with an Application Domain Extension (ADE) for the Energy Performance of Buildings (EPB).

Convergence of BIM and CityGML

CityGML has strongly influenced the development of the INSPIRE BU model, both for 2D and for 3D profiles.  The concept of a base model defining semantic objects, attributes and relations which are required by most applications has been adopted by INSPIRE BU (as core profiles).  The concept of External Reference to link to more domain-specific information systems or to ensure consistency between 2D and 3D representations of buildings has also been reused in INSPIRE BU.  The design pattern of Building – BuildingPart aggregation is also included in the INSPIRE applications schemas. Many attributes (e.g. RoofType, YearOfConstruction) have been included in INSPIRE BU profiles.
 
Many use cases that were considered for INSPIRE BU require a three-dimensional representation of buildings such as a building information model (BIM). Examples are noise emission simulation and mapping, solar radiation computation or the design of an infrastructure project. To allow for that, the building representation in Level of Detail (LoD1 - LoD4) of CityGML has been added to the INSPIRE BU model as a core 3D profile.  The whole content of LoD1 - LoD4 including  features attached to buildings such as boundaries, openings, rooms are the base of the extended 3D profile.

For large scale energy performance at the urban level,  detailed interior elements of each building are not required.  It is possible to work at a simple Level of Detail 3 (LOD3) and include elements like roofs, envelope walls, and windows.  This can also be used to make a comparison with other data sources such as aerial thermal images.

Energy usage data exchange

Green Button implements the common-sense idea that electricity customers should be able to securely download their own easy-to-understand energy usage captured by their smart meter.  Not only does it provide the retail customer with access to their usage data , it also provides the ability to authorize a third party service provider to access his or her energy usage data directly.  This architecture presents a consistent mechanism for authorized exchange of energy usage information.

To integrate electric power usage information from smart meters into SUNSHINE, the GreenButton specification defined by the NAESD (North American Energy Standards Board) was identified as the preferred implementation option for the meter data exchange protocol to be used in Sunshine.  IEC 61968-9 was judged to be much more complicated and less supported in terms of practical examples and software tools.

Open, standards-based foundation for urban energy performance analysis

Together INSPIRE BU, CityGML with the energy performance ADE, and the Green Button specification for energy usage data provide an open, standards-based foundation for energy performance analysis for urban environments.

Building energy performance optimization using BIM and an integrated project delivery approach

As part of a seminar series supported by the Algonquin College Office of Applied  Research & Innovation and the Canada Green Building Council Ottawa Chapter, Jean Carriere, President and Building Performance Technologist at Trailloop gave a seminar on integrated energy modeling.  

The seminar was intended to give an overview of how to design high performance buildings using leading edge methodologies to optimize energy usage and analyze life cycle costs.  

Integrative energy modeling is about optimizing energy usage over the entire lifecycle of the building for multiple objectives. An integrated project delivery process based on building information modeling (BIM) enables the energy performance designer to collaborate with others in the design team on a common platform.  From a cost perspective, designing a building for efficient energy usage is more expensive in the early design and construction phases, but it reduces building costs over the entire lifecycle.  LEED v4 includes a credit for using an integrated project delivery process.

The primary motivation for energy performance modeling is currently aggressive building codes that push energy efficiency, for example, customer driven certification such as LEED and other "green" certification, and financial incentives from local governments and power utilities to reduce energy consumption, peak load or both. LEED v4 incorporates up to 18 credits for demand response. The EU, US and Japanese governments have already mandated net zero energy, near zero energy and zero emissions for public and other buildings starting as soon as 2018.

BIM

While building information modeling (BIM) is not a requirement of energy performance modeling for buildings, Jean has found that it simplifies creating and maintaining a model that can be reused and it facilitates collaboration with engineers and architects who need to understand the results of the energy performance analysis. It also provides a degree of future proofing enabling the information stored with the BIM model to remain accessible throughout the lifetime of the building.

Jean not only uses BIM (Revit in his case) to create and maintain the spaces, walls, and other aspects of the building that are required for the energy performance analysis, but also as a visualization tool for presenting the results of the energy analysis to the mechanical engineers and others who need to understand heating and cooling requirements of the building at a very granular level.  

The BIM model required for energy performance modeling does not require a lot of detail.  Jean estimates that on the industry scale for level of development (LoD) or level of detail, an energy performance BIM model is about at level 250.

Jean tries to use industry standards wherever possible, either de facto standards like Revit for BIM design, or an industry standard like gbXML for migrating the model from the BIM design tool to the energy performance application. Jean use a commercial energy performance analysis IES-VE, but other tools can import gbXmL models such as the DoE's open source EnergyPlus.

Jean uses a tool called BIMLink from Ideate to populate the BIM model with the results of the energy performance analysis.  With Ideate BIMLink, you can pull information from a Revit file into Microsoft  Excel and push BIM data from Excel into Revit.  Jean uses BIMLink to push all the information that the mechanical engineers need to design lighting, heating and cooling into the BIM model, where is can be queried.

Jean relies on young graduates to develop the BIM models for his energy performance modeling projects and he finds that it is relatively easy to find recent graduates with Revit training to create and maintain BIM models. 

Energy performance modeling

The typical process that Jean and his team typically follow to optimize energy usage for a new building is

1. Use Revit to create a BIM model of the building.  If there is an architect's BIM model, an energy performance BIM can be derived from that or alternatively from CAD drawings.  The model has to be very "tight" - not leave holes in walls or empty spaces. It doesn't have to be complex, but all spaces have to be enclosed and all windows represented. This involves some tricky modeling for non-rectangular spaces, for example.
2. Create custom schedules in Revit to provide an information framework for the data that is required as input for the energy performance analysis and for storing the results of the analysis.
3. Generate the gbxML model from Revit.
4. Import the gbXML model into IES-VE.
5. Clean-up the model and add external features such as nearby buildings.
6. Run the energy performance analysis.
7. Export the results of the analysis from IES-VE into Excel and use BIMLink to populate the custom schedules within Revit.
8. Make the BIM model with the results of the energy performance analysis available to the mechanical engineers.
9. Collaborate with engineers so they understand why a room needs extra cooling or more artificial lighting, for example. This can result in changes to the building design.  
10. Iterative design - iterate this process to incorporate changes suggested by HVAC engineers.

Demonstration

Jean demonstrated elements of this process showing

• creating the Revit BIM model
• using Excel to create custom schedules for the BIM model
• generating and importing the gbXML model into IES-VE
• cleaning the model up in IES-VE
• exporting the geometry from IES-VE to simplify and get rid of extraneous objects
• reimporting the simplified geometry file
• using Excel to add room ids, thermal templates and other tabular information required for the simulation
• running simualtions such as thermal analysis, daylighting analysis, etc
• exporting the results back into the BIM model using BIMLink

Future

Jean foresees some important future developments

• Energy performance audit for existing structures - Jean foresees that a similar process could be used for existing structures, using scan to BIM to create a BIM model and an additional calibration step to ensure the base model reproduces the observed bldg performance.
• Operate and maintain (O&M) - Jean estimates that the BIM model incorporates 45 % of what facilities management (FM) would require to operate and maintain the building from an energy usage perspective.

Mobile scanning interiors of buildings with automatic feature extraction for energy performance modeling

At the SPAR International conference Avideh Zakhor from the University of California Berkeley gave an enthralling presentation about her research on capturing optical and thermal point clouds of the insides of buildings using a portable backpack containing a collection of sensors.   Her team has also developed analytical software tools for generating floor plans, distinguishing rooms, identifying staircases, texture mapping surfaces, identifying windows, finding heat sources such as computers and human occupants, identifying lights, and even estimating plug load lower consumption - all automatically. The software her team has developed can generate input in the form of an IDF file for the Department of Energy's EnergyPlus energy performance analysis program. Avideh said that soon it will also be able to generate a gbXML file, which can be consumed by almost all building energy performance analysis software.

Man portable system

 

The "man portable system" her team has developed is a 32 pound backback with a collection of sensors.  There are sensors for accurately tracking the six degrees of spatial freedom which determine the location and orientation of the backpack in addition to sensors for recording optical and thermal point clouds. The operator walks through the building going into all rooms, halls, stairwells and other human accessible spaces. With the backback this is a much faster process than capturing indoor spaces with static laser scanners. For example, Avideh's team was able to scan Union Station in Washington DC in a matter of hours. A comparable static scan takes days.

 

Automated feature extraction

 

The resulting georeferenced data is then offloaded from the backpack and analyzed to generate different 3D data products including optical and thermal 3D point clouds, a colourized 3D point cloud, surface texture map,  and triangulated mesh surfaces.  Two different triangulated surfaces are generated for different applications - a very detailed surface and a much simpler model of spaces and walls. Using these data products the software automates feature extraction. It can distinguish  windows, staircases, and individual rooms and generate a floorplan.  Surface textures can be added to create a 3D photorealtistic rendering.  By analyzing both the optical and thermal point clouds the software tools can identify heat sources including computers and human occupants and can even identify lights and estimate power plug loads.

 

Building energy performance modeling

 

Usi‎ng the results of the automated feature extraction the software tools can be used to generate the input required for a building energy performance audit. Currently the tools are able to generate input in the form of an IDF file for the Department of Energy's Energyplus whole building energy simulation program.   Avideh said that soon it will be possible to generate an gbXML file, which can be consumed by most building energy performance analysis applications including IESVE and Green Building Studio.  This clearly has the potential to convert what is now a slow, manual, expensive process into a fast, repeatable, affordable process.

Improving energy performance of buildings in an urban environment using 3D models

The European Union has set itself agressive goals to reduce GHG emissions by 20%, increase renewables share of energy generation to 20%, and to reduce energy cinsumption by 20% by 2020.  The EU seems to be on track for the first two goals, but the third remains a challenge.  In the EU something like 40% of energy is consumed by buildings, heating and lighting being the largest factors.

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Yesterday at the GI_Forum Symposium, Wolfgang Wasserburger gave an overview of a project SUNSHINE (Smart Urban Services for Higher Energy Efficiency) focused on energy efficiency for buildings in an urban environment.  Sunshine is a European funded project that started a few  months ago and is intended to continue for 36 months.

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Energy certification of buildings is a key policy instrument for reducing the energy consumption and improving the energy performance of new and existing buildings. It is expected to help increase demand for high performance buildings by improving the energy performance of the building stock in urban centers. SUNSHINE is intended as a step towards toward such a policy and a way to  contribute to improving the energy efficiency of buildings.

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SUNSHINE is intended to be accessible to Web and mobile platforms. An interesting feature of the project is that it is planned to develop an extended CityGML model for representing urban structures for energy performance modeling.

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Three use cases are being considered.

.

1 Assessment of energy performance

The goal is to supports the automatic large-scale assessment of building energy performance based on publicly available data. The building energy performance models will be used for energy.density mapping ("ECOMaps") .  It is intended that an ADE extension to CityGML for 3D building energy modeling will be developed.

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2 Heating and cooling forcast and alerts

This focusses on existing buildings that have been selected for energy performance improvement.  It relies on localized weather forecasts and other information to forecast heating/cooling requirements to optimize energy performance..

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3 Optimization of power consumption by public lightimg

The idea is to control illumination so that areas are only illuminated when people are present and the level of natural lighting requires it.

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SUNSHINE will be piloted at nine sites across five countries that include 20 public buildings in Ferrara, 60 technical buildings in Trentino, and public illumination sysems in several Italian cities.

Modeling downtown The Hague to reduce energy consumption

I've blogged previously about a project by the Los Angeles Community College District, the largest community college district in the U.S., create 3D BIM models of all the buildings on the LACCD  campuses.  One of the most important motivations for creating these models was that BIM models would faciliate energy performance analyses of LACCD buildings.

Reducing energy usage in The Hague

At the Geospatial World Forum 2013 (GWF 2013) conference in Rotterdam Martinus Vranken and Jene van der Heide of the Dutch Kadasre described a project to model a square kilometer of downtown The Hague with the objective of reducing and stabilizing energy usage and costs for the entire area.

The Dutch Ministry of the Interior has initiated a joint project with the Municipal government of The Hague to reduce and stabiize energy usage and costs in downtown The Hague, including the use of renewable energy.  The study area is roughly about a square kilometer of The Hague where the buildings are large and mostly owned by the National and Municipal governments.  The Dutch Kadaster has been contracted to provide an information system to assist the Ministry of Interior in developing a business case.

The Kadaster has combined its own data with that from other government agencies

Kadaster

• Topography
• Ownership and building information
• Energy labels
• Underground grids electricity, gas and heat
• Monuments

Ministry of the Interior and City of The Hague

• Energy consumption
• Employees
• Surfaces suitable for solar panels
• 3D model

Province of South Holland

• Heat pump facilities
• Solar probability map
• Wind probability map

Ministry of Economic Affairs

• Geothermal facilities
• Permits for geothermal concessions

The Kadaster has assembled land registry information like ownership, monument status; building information such as year of completion, surface area, energy labels, energy indices; information on underground networks like heat networks, gas and electricity grids; together with government information on heat pump facilities, energy consumption of buildings, and available building facade area suited for solar panels.  Combining this information provides a tool that the Ministry is using to develop the busness case for a new form of energy supply that is reliable, clean, and affordable.

The two main challenges have been to translate this information to fit the perspective of the Ministry of the Interior and structuring the information so that it can be reused for similar projects in the future.

The next steps  on the project are data collection and processing, defining business case,  and tendering and then transition to the new energy supply.

The lessons learned so fare are interesting.  First of all, visualization using a geospatial information platform has been vital in developing the business case.  This approach has provided important Insight into the energy and heat exchange possibilities between buildings and enabled exploration of the possibilities of solar, wind and geothermal energy.  The geospatial approach also provides a platform which the private sector can use as a foundation in preparing bids for the project.

There is a video about this project available here.

State of the art: Energy performance modeling for buildings

Yesterday the Ottawa Chapter of the Canadian Green Building Council sponsored a presentation "Building Green in a Collaborative Virtual Environment" by Jean Carriere of 3DEnergy, Ltd.

Where we are now

Jean gave an overview of the state of the art for energy performance modeling for new buildings.  To summarize, there are a lot of energy analysis tools (lighting, thermal, emissions, water usage, etc) , many are very complex, and the volumes of data that are required is increasing exponentially. Interoperablity is one of the biggest major challenges that is inhibiting productivity in energy performance analysis.

Energy performance modeling is a new field, so new that there is no set of standard best practices.  Energy modelers are making it up as they go.

Another important factor inhibiting the full benefit of energy modeling is that it is rarely used in the conceptial design phase of a building project when its impact would be most significant.  In Jean's experience he is called in after the architect has completed the basic design, during the design development and construction documentation phases.   This late in the game there are severe limits on what can be changed to optimize building energy performance.

One of the most, if not the most important, motivations for conducting an energy analysis for a new building in Ontario are programs run by the Ontario Power Authority (OPA) that provide direct payments not ony for reducing the energy load of a building but also for the energy analysis itself. The program that Jean cites most often is the High Performance New Buildings (HPNC) program that pays $400 to $800 to the builder for every kW of electric power saved over what is mandated by the Ontario Building Code (ASHRAE 90.1 2010).   Regulation is also starting to be an important factor as well.  In Ontario there is a new regulation that requires that any building with 40% or more glazing has to be 5% more efficient than ASHRAE 90.1.

Trends

There are important trends that are emerging that point to where the industry is headed.

BIM

First of all, from Jean's perspective the natural place to start energy modeling is with a Building Information Model (BIM).  There are several reasons for this.  First of all it is what many of the energy performance analysis packages expect and it is supported by the gbXML standard.  Secondly it allows all the information required by the architect, engineers and construction contractors to be accessed in one place.  And thirdly it helps in communicating the results of the energy performance analysis to the people who need it including heating and cooling, lighting and other types of engineers, all  of whom may require the same  information but communicated in dfferent ways.

Interoperability standards

From Jean's perspective the big challenge is getting the right information stored in the BIM model into the energy performance analysis package.  Jean sees interoperability as having the biggest productivity impact on the energy analysis process.  Jean has put a lot of effort into streamling the flow of building properties from the BIM model to the energy analysis package.  He relies on the gbXML open schema to transfer building properties stored in the BIM model to engineering analysis tools.

Jean has focussed particularly on hospitals and reports that after working on several hospitals he has optimized the process so that starting from paper architectural drawings, he can develop the BIM model, compile energy performance parameters, generate gbXML, and conduct a complete energy analysis (daylighting, thermal analysis, etc)  for the proposed building in only two weeks.  People in the audience were astounded at how quickly Jean is able to do this.  One person cited several months as their typical experience in doing an energy analysis of a building design. 

Getting the biggest bang for the buck

Jean showed a fascinating graph that compared the energy reduction impact of various strategies.  I and a few others were surprised that daylighting, reducing the need for electric lighting, is one if the easiest strategies to implement and is one of the most effective way to reduce energy usage by a building.   

Training and education

One of the challenges that has to be addressed, and that educational programs like this one organzed by the CaGBC, is making everyone involved in construction, but especially those involved in the early conceptual design phase, more aware of energy modeling.  Currently on many design/build projects, one group does the conceptual design, which is then handed over to a second delivery group that developes the schematic design and builds the building (and often leaves detailed design to the construction contractors.)  Jean rarely gets a chance to work with the conceptual design group, who are often not that conversant with energy performance of buildings and the important implications some of their design decisions have for the energy performance of the finished building.  By the time the delivery group calls Jean in to conduct an energy analysis, design decisions that could have dramatically changed the energy profile of the building have already been made and at that point are cast in stone.

 Future

The future is net zero energy buildings.  I have blogged about the mandated objectives for near zero energy buildings in the EU, the emerging objectives for zero emissions buildings in Japan, and the Federal objectives for net zero energy buildings in the U.S.  Buildings that either use net zero energy or even contribute more energy back to the grid than they consume are clearly the future.  But getting there will require changes in how we design and build. 

First of all, from Jean's perspective energy analysis has to happen earlier in the design/build cycle.  Secondly, it will require much more collaboration than is typical of the overwhelming majority of construction projects.  Integrated Project Delivery (IPD) where everyone involved in a project work in the same big room is an example of the type of collaborative approach to construction projects that could enable much greater energy savings.

Some of the things that are on Jean's radar as we move toward net zero energy buildings are ASHRAE 189.1 a standard for the design of high-performance green buildings, standard building energy modeling procedures and guidelines (COMNET), and the zero energy performance index (zEPI), which is the ratio of the energy performance of a building to the average energy consumption of a similar building at the turn of the millennium that is operated in a similar climate, for similar hours of and similar operating conditions.

Conceptual energy modeling in a simplified BIM workflow

Project Vasari is a technology preview of a simplified design tool for creating conceptual building designs with integrated analysis for energy and carbon. Vasari is for early concept work.  One of its big differentiators from products like Sketchup is that it is intended to fit into a building information modeling (BIM) workflow.

Project Vasari has been sponsoring a series of talks about different aspects of the project.  The next one is specrficially about conceptual energy modeling.  By understanding the big picture energy implications of a building design early you can save time and money by identifying the key energy drivers.  In this talk Lura Griffiths, LEED® AP BD+C, E.M.I.T Senior Energy Analyst at Glumac, will present several examples of real building designs and how their energy performance was analyzed in the early stages of design using conceptual energy analysis.  The results of the early analyses helped guide the design and make significant impacts on the energy use of the buildings.

Date: August 8, 2012

Time: 11:30 AM Eastern time

You can register here.

Reducing electrical demand through energy efficient buildings

I heard a very interesting presentation on energy modeling for buildings with a focus on reducing electrical load at the GORUG meeting here in Ottawa.  Energy efficient building are becoming a priority for many utilities in the U.S., Germany and other locations.

Jean Carriere, an energy modeling specialist at 3D Energy Ltd, gave an insightful overview of what's involved in energy modeling from the point of view of a designer who is familiar with building information modeling (BIM).  The kind of design decisions that energy modeling helps with are

• How much energy should my building use ?
• Could I power it with solar PV or wind (Ontario has a feed-in-tariff program that encourages small scale renewable energy development) ?
• How much insulation is cost effective ?
• How sensitive is my building to changes in weather ?

Compliance

The motivations for conducting an energy analysis include the revised Ontario Building Code, LEED and other types of certification.  In Ontario, new buildings with 40% or more external glazing are required to conduct an energy assessment. After January 1, 2013 new buildings will have to exceed ASHRAE 90.1-2010.  In addition the High Performance New Buildings program rewards builders with incentives for offsetting the cost of energy-efficiency measures.  According to Jean you get compensated for every kW saved.

I blogged previously about a new LEED program fro commercial buildings focussed on demand response and reducing peak electric power usage.

An energy analysis allows you to determine how much energy your building will consume in a year, cost effective insulation and glazing, and other things that you can do as part of the building design to opimize energy usage.  An energy analysis requires a lot of data and according to Jean inputing the data is still a very manual process that takes more time than it should.  Simulation applications allow you to include local environmental conditions and conduct thermal modeling, daylight and airflow simulations.  Thermal modeling includes energy consumption, thermal comfort, CO₂ emissions, renewable energy integration, and electric power load. Natural lighting includes visual comfort (glare) and the reduction of energy use through natural lighting.  Airflow silumation includes external wind simulation, internal airflow simulation, clean room ventilation, and reduction in electrical load as a result of using natural ventilation.

Workflow

Jean devoted most of his talk to the workflow he uses to conduct an energy analysis.  In most projects he is brought in after the building has been designed which significantly limits the opportunity for optimizing the design of the building for energy usage.  He typically starts of with the architect's BIM model and a database containing information about building elements as well as local envrionmental conditions. 

The frist thing he does is to create a parallel model, which is a simplified BIM model derived from the architect's model that contains the key elements that are required for the energy analysis usch as simplified walls and floors, room bounding elements, complete volumes, and window frames and curtain walls.  He exports the simplified model as gbXML to an energy analysis package and runs a simulation or several simulations if he is able to consider alternative designs.  The simulations generate a lot of data which he analyzes. 

Finally, he uses a visualization based around the BIM model to communicate the conclusions derived from the analyses.

Standards

Jean repeatedly emphasized how standards, for interoperability like gbXML and for classifying building elements in BIM models, could contribute to streamlining the workflow for enegy analyses.  He specifically mentioned Industry Foundation Classes (IFC) and Zero Energy Performance Index (zEPI), and it would seem that other standards for classifying elemnts in BIM models such as COBie and Omniclass could play a role in this as well.