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Posts Tagged Model Calibration

Going-Green (2)Last month I had the pleasure of being involved in the 4th Going Green Conference, which took place in Gauteng from 18-20 October. Hosted by the Green Building Design Group in partnership with the Gauteng province, the organisers aimed to “create a more connected platform for all the various actors in government to engage and to recognise that public assets can be used as a test case and lead by example to the wider country objectives on these policy directives.”

What set this event apart from some of the others I’ve attended was the focus on knowledge sharing and creating a platform for the private sector to share their knowledge with the public sector and with final year university design students from both Architectural and Engineering fields. Click here for an insightful synopsis of the event from Songo Didiza, Executive Director at the Green Building Design Group.

IES have a wealth of practical experience and measurable results from analysis of various buildings across the world. There is a global awareness of the power of data, but we need to further exploit this data to improve our buildings in South Africa. With this in mind, the topic I chose from my presentation was: OMG! Operational data + Modelling = Great Savings.

The presentation focussed on the need to evaluate building performance against design intent, and quantify operational gaps in the same level of detail with which we analyse design in simulation software. To do this, we need to consider the feedback loops that can exist within building lifecycle data, and how this should be managed by BIM processes. Designers can benefit from lessons learnt on previous projects, and the O & M team can benefit by an audit trail of the design intent and records of commissioning procedures and tests for the building they are managing.

At present, buildings are often an untapped data asset. By taking the operational data from buildings and using it to calibrate the operational model, we can generate highly accurate calibrated models, which enable owners and FM’s to analyse planned interventions and evaluate their impact with a high degree of accuracy, to assess viability before commencing work.

Let us consider a single data stream from a building. If we view monthly metred data, we have 12 data points, but if we have data measured every 30 minutes by a smart meter, we have 17520 data points! If we then collect data from several streams, the potential for a clear image for comparative analysis increases, especially where this data is logged effectively, clearly named and well managed.

Data-points-view

It is estimated that 80% of cost lies beyond the construction team involvement. For any client with a portfolio of real estate, there are real benefits available from data analysis:

  • Creation of benchmarks, to identify low or high performers and outliers, indicating a need for further investigation of the building fabric and systems, and its operational strategies.
  • Support both better informed design of new buildings, and future strategy for O & M

In my presentation I presented various healthcare examples of where our IES consulting team have assisted with BMS Data Logging and collation on a cloud-based platform, enabling data reviews for:

  • BMS analytics, including tracking and monitoring building performance
  • Independent performance review through auditing the building against its Key Performance Indicators
  • Energy consumption benchmarking Building Simulation was then used to propose suggestions and evaluate their impacts and compliance.

The unique skillset of our consulting team enables our analysis to compare different results and postulate reasons for the differences. For example, we utilised BMS data logging and analytics to evaluate a portfolio of 6 similar healthcare facilities. In reviewing the supply air pressure data for the operating theatres, we identified many opportunities for immediate savings from operational decisions, as shown below.

Supply-Air-Pressure

The technology is available now to deliver projects that incorporate BIM and energy modelling in an integrated design process that extends to building hand-over, commissioning and facilities management. As owners start to demand buildings which operate closer to design predictions, we can start to use operational data to inform dynamic building simulations of improved design and retrofit, and provide enhanced operational models that enable ongoing monitoring of performance and great savings.

If you want to find out how more about how operational data + modelling = great savings, drop me an email and I can provide you with more information about my presentation. I have no doubt that the 5th Going Green Conference will be even better and I look forward to being involved in more knowledge sharing again next year.

Operational BIM and Calibration

The world of energy efficient building design is littered with acronyms and jargon – CAD, BIM, SBEM, DSM, energy modelling and BREEAM to name but a few. Now as we strive to bridge the ‘performance gap’ operational BIM, BIM 4 FM and calibrated simulation are being joined by BMS, AMR and BEMS. But just what are the benefits of combining the technology and processes behind these jargon laden phrases to the average building owner?

We’re currently at a technology cusp. CAD (computer Aided Design) techniques being used at the design phase are the default choice, and being joined by both BIM (Building Information Modelling) and building analyses technologies.

The issue is that these buildings do not always operate in real-life the same way as their design intended. This is sometimes called the performance gap. Misunderstandings around the difference between the energy model done to prove compliance with building regulations and an energy model of the actual building don’t help, as don’t last minute specification changes, lack of detailed commissioning, and disjointed handover to the building owner.

Its fast being recognised that ensuring design intent is handed over correctly as the building is completed and starts operating is a necessity to bridge this difference between predicted operation and actual operation – the process of well managed building handover is known as ‘soft landings’.

3D models of buildings created purely for geometry, or for performance modelling, or as part of a BIM process are being recognised as a way to gather, store and pass-on important data related to a buildings’ operation. Using an Operational BIM or BIM for FM approach offers many benefits by aligning construction and design to the operational use of the asset.

However, taking this one step further, an innovation known as ‘calibrated modelling’ links together all operational data streams from a building (including Smart/AMR Meters, Sub Meters, BMS Equipment, Environment Sensors, other building systems such as lighting), with other available external data sources (such as weather), with 3D analysis models. This means that real data rather than design data can be used directly in calibrated energy models (or simulation models) enabling more accurate predictions.

One of the key strengths of this approach is its value of being used after initial operational energy efficiency improvements have been made and its capability to find more improvements. It can either be applied to a building for a fixed period or can be used on an ongoing basis to support a programme of continuous improvement depending on the individual application. It can also be used as part of a retrofit process (light or deep) in order to assess different options and make sounds business case-led decisions.

Key points of calibrated modelling are:

  • Advanced data analytics helps find ‘hidden’ cost and resource savings through smarter system control and smarter ways to gather and analyse data
  • By analysing actual performance against virtual models and utilising climate-change/ weather files, it can catch operational drift, identify energy reduction areas, improve efficiencies, and inform deep retrofit
  • Is applicable across a wide range of scenarios which can be modelled simultaneously : whether you are dealing with enhancing building operation or undertaking large scale retrofitting
  • Is relevant as part of a BIM for FM strategy (due to its use of 3D analysis models)
  • Allows operational data and simulation BIM technology to be used at all stages in the building lifecycle from design, through commissioning and hand over on into its first year of operation and beyond
  • Delivers energy demand reduction through operational efficiencies as well as retrofit (helping to reduce risks and validate the most appropriate strategies) which has the added benefit of ensuring renewable technologies deliver the right proportion of the energy load
  • Enables Future Proofing – ability to take future climate predictions into account ensuring highest possible asset and building values now and in the future

So where could the future take us? It is not hard to envision how a 3D simulated environment could be exploited to intelligently control buildings. Model Based Control, Fault Detection Identification Analysis, Optimisation of the Building operation while in use and Predictive Control based on future weather and operational data, are all areas currently being researched across Europe.

As part of World Green Building Week IES is running an education session, followed by drinks on this subject. Taking place on Thursday 24th September 4-7pm in central London the session is aimed at both building owners and those responsible for their operation as well as consultants working in this area. Using case study examples it will look at how new technology in this area can enable operational data and performance simulation technology to be used together to drive efficiencies and close the performance gap at all stages of the building lifecycle from design, through commissioning and handover on into the first year of operation and beyond.

Sign up here: Technology Update: Driving Building Efficiency Using Operational Data & 3D Modelling

 

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