Copyright © 2009 Integrated Environmental Solutions Limited. All rights reserved
An article appeared in the Telegraph last week, Energy Scandal: Misleading Efficiency Claims Leading to Huge Bills for Homeowners. At IES, while we’re 100% in support of the industry needing to do much more to tackle the energy performance gap, we feel that this article unfairly lays the blame for it at the doors of energy modelling professionals.
Headquartered in Glasgow, IES is the main provider of performance simulation software in the UK. We’ve been helping address the numerous causes of the performance gap for several year’s now, through training and education sessions.
Yes, the ‘performance gap’ is well documented and known about in the industry. But to address it requires action by all those involved in a building’s life cycle, from design to operation. That includes architects, engineers, energy modellers, contractors and facilities managers to name a few. The finger should not just be pointed only at building modelling professionals!
There are a number of issues in play here.
First off, a key misconception to understand, is that an EPC, as modelled by software during the design stage, is NOT a true reflection of how a building will perform once built. EPCs assess a building under normalised conditions, missing out ‘unregulated building energy loads’ that are not required to be included in the calculation. As an industry, we need to get away from modelling just for compliance and modelling for actual building energy use. Read more on our views on this here.
Next up there are already several well-established industry initiatives aimed at tackling the issue. CIBSE Guidance TM54 is focused on ‘Evaluating Operational Energy Performance of Buildings at the Design Stage’, and the BSRIA Soft Landings Process aims to help to solve the performance gap between design intentions and operational outcomes by better management of the handover process from design, through commissioning, and on into operation to deliver a better performing product.
Combine this with, the digital revolution of the construction industry that is Building Information Modelling (BIM), and the industry has a vehicle to capture relevant information during design for use during the operational phase of the building as well as accountability for operational performance.
So what’s the problem? Ultimately, building clients want low fees. To move away from a compliance only modelling approach that uses standard assumptions and leaves predictions of energy use way out, needs the support of clients. When done properly a building model can predict within +/- 5% of energy performance. But time and effort needs to be taken during the modelling process to predict realistic use. And time costs money!
In reality, this research just highlights why modellers use software tools to understand building energy use. The way a building responds in practice is complex with many factors interacting and needing to be accounted for. Modellers use tools like the IESVE to run scenarios and check their assumptions are correct. They often change their views based on feedback from models. The energy modellers that took part in the research were not asked to use any modelling software to inform their responses.
This is why tools like IESVE exist, to aid professionals in making informed decisions. All IESVE modellers can access detailed training and accreditation from us, and we would wholeheartedly support more courses, and in-depth, industry wide accreditation.
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.
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:
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:
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.
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.
I recently conducted an energy survey at a new healthcare facility and a couple of headline numbers jumped out which I thought could do with some further investigation and validation. So the focus of this Post is specifically around the application of Energy vs Cost Modelling within the Building Performance Analysis industry.
So here are the facts:
The story sounds ok so far until you consider the total Project Value, a £29-million design/build cost. If we do some very basic lifecycle cost modelling the numbers look like this:
[Note: No Utility Rate increases, NPV or Discount Rate allowances made in this basic calculation]
As the calculations stand this facility would therefore take 30-years to have a cumulative energy spend of £3-million.
Let’s say that 20% energy savings could be made fairly easily via a £20k energy efficiency spend and that a 1-year ROI would be achievable. So a £20k up front spend on energy efficiency measures generates £20k worth of savings by the end of the first year. Assuming this £20k reduction could be maintained for the remaining 29-years a cumulative saving of £580,000 could be made over the 30-year range.
A 20% saving is a 20% saving and who wouldn’t want an extra £580k in their annual budget, but is it really worth waiting 29-years for?! It seems like such a long time to wait.
Now if we look at the £580k from the total Project Value perspective (£29-million) it’s works out as only 2%.
So here’s the point. If 2% could be shaved off the total Project Value up-front at Design/Build stage the £580k saving becomes money up front, cashed in the bank from Year Zero – money that doesn’t need a 29-year wait to get back in hand. To me this sounds like a better deal for any building Owner/Operator?
If we look at this from the Building Performance Modelling perspective it gets interesting. We spend fees on Energy Modelling and associated analysis for Green Building Certification schemes (BREEAM, LEED etc) but do we really use these intelligent 3D models to their full potential from a Cost modelling perspective?
Surely with the BIM analysis models that are being developed for purposes of Building Performance Analysis (Energy, Daylight, Natural Ventilation, Overheating studies etc) it’s an easy transition to further develop these models as accurate Cost models? In this way more time and resource could be used on predictive modelling of Cost based scenarios? We’re all well versed in scenario based energy modelling (e.g. multiple changes to a wall U-values, HVAC plant efficiencies etc) and we can predict the resulting % energy savings such measures will have against a baseline figure, but do we really consider these ‘energy’ measures from a Cost perspective?
I will continue on this same theme in a future Post but am interested to hear the industry feedback on this to date. How many Building Performance Analysis teams out there are actively involved in BIM based Cost modelling on a day-to-day basis? Where do you get the data for the Cost models? Is there more that the ‘modelling’ industry can do to populate better Cost models – or is it simply a bridge too far with insufficient Cost datasets currently available? Is a dedicated Project Quantity Surveyor needed for a detailed Cost analysis or can the modelling industry do more to support early stage scenario based Cost modelling of this nature?
On the lead up to our free BIM4Analysis webinar taking place on Thursday 28th January, we’ll be publishing a series of blogs to preview some of the topics that will be covered during the session. First up is a post from our guest speaker Jean Carriere of Trailloop, who will be presenting the most recent thinking on his approach to producing building loads for systems sizing and energy modelling from an integrated modelling process.
Build clean models before exporting the gbXML file and avoid integration errors before they happen, yielding predictably good results across many applications.
The AEC industry is familiar with creating building loads for systems sizing and then producing energy models with the Performance Rating Method (ASHRAE 90.1 or NECB). Although these project deliverables are typically done independently from each other without any integration to the project’s architectural and MEP systems design.
The building loads are produced from an early snapshot of the building’s form and features, then the compliance energy model acts as an auditing tool when the design is complete. A framework that incorporates these familiar industry deliverables would improve the energy performance of any building, by integrating and using information effectively during the design process.
The objective is to create the building loads from the architectural design model and then use this information to design and right-size the HVAC systems. With a clear and robust framework for measuring and verifying energy performance indicators, the design team can make informed decision based on actionable metrics. This process is designed to promote iterative energy simulations in order to achieve certain energy performance targets, such as net zero and beyond.
In order to make this process work, it first starts with the integration of BIM for energy modeling applications. This is accomplished by exporting a good quality gbXML or IFC export file from a BIM project. These files can be imported into most energy modeling applications, which then creates a digital link between BIM and energy modeling. As the federated BIM project evolves in complexity and level of detail throughout the design process, the energy modeling integration link is lost, but the information parameters remain. If the geometry or spaces change after the integration, the modifications can be copied back using the 5 fundamental modeling techniques into the integration model and then re-integrated in order to maintain the BIM link between applications.
We can use these information parameters to exchange data between the two applications. That could be a third party defining space and component properties in Revit and sending that information down to the energy modeler. Or it could be the energy modeler producing building loads or systems data to be inserted within the relevant space and component parameters. This way the building’s information resides inside the BIM and the simulated data is accurately representing the architectural and mechanical/electrical design.
The process of exchanging information bi-directionally between BIM and third party application is where the UK is heading with their BIM mandate for 2016. They define level 2 BIM as “a single environment to store shared asset data and information; accessible to all individuals who are required to produce, use and maintain it.” In essence, we’re opening up a portal to move information between energy modeling and BIM applications. If you’ve maintained the integration model throughout the process, then exchanging information after an energy simulation is as simple as copy/pasting data in Excel, and in a few minutes your BIM project is filled with important and relevant data.
Want to find out more about Jean’s approach? Sign up now for our free IES Faculty BIM webinar.
Got a question you’d like to put to Jean or one of our IES BIM experts ahead of the webinar? There are a number of ways you can do this – submit your question here, tweet us using the #BIMfaculty hashtag or post on the IES Facebook page, and we’ll do our best to report back during the seminar. Questions and answers will be collated into an FAQ document which we’ll circulate after the event.
On the build up to this year’s ASHRAE Energy Modeling conference in Atlanta, ASHRAE have launched the new Lowdown Showdown modeling challenge. ASHRAE have put together a selection of teams consisting of engineers, architects, designers and energy modelers, who will be coached by software vendors including IES, as they compete to design and model a net-zero energy building.
The challenge, which started in June, will run for 3 months on the lead up to the conference that kicks off at the end of September. Each team has been given a baseline building, which they must then work on together to create a design proposal that demonstrates net zero energy performance.
The teams will present their final design on October 1st at the ASHRAE Energy Modeling conference. The “LowDown Showdown” projects will be voted on by the conference attendees and will be judged on Energy Use Results, Creativity, Innovative Workflow and Teamwork.
I’m very excited to be working with the group that ASHRAE have assigned to the IES team. ASHRAE have given us a tricky challenge but I’m confident in the talent on the team, and that they’ll overcome and surpass expectations. Our team consists of the following members:
Ben Brannon (Arup)
Anna Osborne (Integral Group)
Greg Romanczyk (exp)
Cory Duggin (TLC Engineering for Architecture)
Shona O’Dea (DLR Group)
Megan Gunther (Affiliated Engineers, Inc.)
Scott West (Jacobs)
Andrea Costa (ACE Energy Concepts)
Even though the team is spread across a massive region, I’ve been lucky enough to meet them all before. On a personal level, they are all really wonderful people and it’s a pleasure to work with them. I’m looking forward to seeing their presentation. If you are too, we’ll see you in Atlanta on October 1st!
The conference is set to be a busy week for IES. Our team will be exhibiting our latest VE solutions and we’re hosting two pre show training workshops – HVAC Loads Sizing and Energy Modeling (http://ow.ly/QNYlk) and Advanced HVAC Modeling (http://ow.ly/QNYq3).
It doesn’t stop there. My IES colleagues Nathan and Megan will also be taking part in the following presentations, so try and check them out if you’re coming to Atlanta…
IES are also hosting a welcome reception for our customers on the Wednesday evening, September 30th – details coming soon.
Check out this great round-up of sustainable analysis tools exhibited at AIA by Lachmi Khemlani, founder and editor of AECbytes www.aecbytes.com/feature/2009/AIA2009_EnergyApps.html.
It includes our new VE-Gaia tool which we previewed there… “IES, the leading vendor in the performance analysis field, introduced a new application, VE-Gaia, to add to its already substantial product repertoire.”
However, it was her comments in the conclusion that really struck a chord with me. It is very encouraging to have finally reached a point where the importance of analysis tools and optimisation of building performance in sustainable design is becoming widely recognised. Enabling this ease of use and access to analysis tools is at the very center of our entire ethos. These are very exciting times for us!
“The increase in the number of analysis tools is a testament to the increasing importance of sustainable design in architecture and the need to optimize building performance. Unlike in the past, when performance analysis was primarily the purview of energy experts, academics, and research institutions, they are now becoming a part of the mainstream architectural toolset, with interfaces that non-technical people can also easily use and understand. Of course, the maxim of “garbage in, garbage out” very much holds true for sustainable design tools as well, and it is easy to be seduced by the colorful diagrams and charts and omit to question the veracity of the input and the accuracy of the output. It’s terrific that we have finally reached the point where the input of building geometry to the analysis tool directly from a BIM application has become a commonplace feature–but we have to keep in mind that geometry is only one of the inputs, and that an accurate analysis depends upon a whole host of other input data that has to be specified correctly as well. It is here that the experiences and insights of an energy expert come in and play a critical role in the design of sustainable buildings. Thus, while it is great to have the tools with their ever-increasing capabilities, it is important to not forget the human element that is ultimately needed for the creation of successful sustainable architecture.”
Lachmi has a Ph.D. in Architecture from UC Berkeley, specialising in intelligent building modelling;Â she both consults and writes on AEC technology. Read the full article and sign up to her newsletters at www.aecbytes.com/feature/2009/AIA2009_EnergyApps.html.