Autodesk Ecotect

Autodesk takes a giant leap forward in the green software industry with the aquisition of Square One Research LTD including substantially all of the assets related to of the Ecotect software tools for conceptual building performance analysis.

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"Square One Research and Autodesk share a commitment to using technology to make the design and construction of sustainable, high-performance buildings easier and more efficient," said Dr. Andrew J. Marsh, Co-Founder and Head of Research & Development, Square One Research. "We are pleased to join Autodesk and look forward to helping develop and deliver simple and effective building performance analysis to architects and engineers around the world."

Autodesk announced simultaneously that it had acquired substantially all assets related to Green Building Studio, Inc., the intent of which they had announced in February of this year.

What the Square One acquisition should mean:

• Improved gbxml workflow
• Improved IFC workflow
• Improved geometry workflow from Revit and other Autodesk applications
• Development of LEED toolkit within Ecotect
• Supported use of Ecotect in conjunction with other energy modelling software
• Improved transfer of metadata for more iterative analysis opportunities
• The View Cube and Steering Wheel now found in all other Autodesk products will be replaced by the Ecotect right mouse orbit and the F5-F8 standard views (please not the other way around)

See related story...

The Engineer Takes the Lead

In this follow up to the "Chicken or Egg" blog I'm attempting to clarify the process, still misunderstood by many.

First it needs to be recognized when designing high performance buildings that we are too limited if we rely on a single energy model which simply calculates overall loads. The concept of multiple models appears inefficient and a departure from what we want out of BIM, but is a reality that can be efficient with a clear stream of data with a clean file exchange.

If we look at the current process we see that engineers are building multiple energy models to fulfill two requirements:

1. Peak loads to size equipment


2. Overall energy consumption for compliance with local code

   

Diagram representing Zone calculations for energy modeling.

What hasn't yet worked well are the efforts made to integrate energy models into the design process. Most efforts in the US to improve this process focus on reassigning the task of energy modeling to the architects who are more able to do it early while (whilst) the results can influence the design. Later in the process the engineer will take charge of the energy model, in theory. Engineers are very excited about the potential to spend less time modeling geometry, but still argue that they need to be brought into the process earlier as they don't particularly trust the architect to do this alone, and will often remodel everything again the traditional way just to validate their results.

The US approach has greatest potential for small offices where the architect often performs tasks without the help of consultants and can now achieve more information than they could previously. Medium and large design firms prefer to rely on consultants for most everything which requires advanced knowledge and skills. To build and understanding an energy model requires advanced abilities--to convey the results effectively, but also to trust them in the first place.

Diagram representing Geometry calculations for environmental analysis

Due to tougher energy regulations Europe and the UK have had more experience and have seen a slightly different process evolve. UK engineers have a greater involvement earlier in the project where they actually use their knowledge and experiences to bully architects into making better design decisions. Architecture firms often bring trusted engineers into sustainability charrettes, or "surgeries," where they will critically evaluate designs for multiple projects that they are not working on. When their involvement begins on a project there is immediately a back and forth between their energy model and architectural analysis models that are focused on specific tasks.

By assigning tasks to the architect the engineer can set the parameters for high performance design that allow the architect to creatively explore and evaluate multiple options. These tasks could be minimizing solar radiation during peak hours, redesigning inefficient shading devices, redesigning the forms or the facade to allow more daylight into spaces, and other ways to reduce loads that the architect can measure without a full energy model. To visual this more clearly I've created a project timeline.

This timeline is front loaded in that Pre-Design makes up about one third of the analysis effort, Concept and Schematic phases combined are the next third, and there is even an analysis phase during Due Diligence. The first two project phases belong to what some buildingSMART experts describe as the Building Investigation Modeling phase, while the Due Diligence here is a new concept for most that will prove to be invaluable to the process. We are all familiar with architectural due diligence relating to local codes and site history and the term "environmental due diligence" referring to site investigation for pollution hazards. But to commit to high performance design we need a broader background check and an understanding that sunlight, wind, water, and daylight are not just opportunities but are also hazards if not fully understood. Before a single line is drawn, collaborative due diligence should help us understand when we will have heating loads, cooling loads, peak values, daylight opportunities/constraints, wind opportunities/constraints, on-site renewable opportunities and more. This information can be gathered from many different sources, but when related to energy performance the MEP engineers should be utilized to set design guidelines from their knowledge of building type and location, or from a basic energy model. Before the designer draws a single line they should have a clear direction of what not to do and where their opportunities lie.

There are many reputable software packages that are able to calculate total energy loads, fewer that are trusted or able to design equipment around peak loads. The software that ultimately will excel in energy modeling will be one that is accepted by local building codes across the globe. But perhaps more importantly this software will be able to reuse architectural design models, architectural construction models, and will promote interoperability by cleanly exchanging data between all design and analysis platforms.

When it comes to environmental analysis for evaluating specific issues early in design there is currently no software comparable to Ecotect in either function or interoperability. But Ecotect is particularly easy to support philosophically because of its commitment to interoperability, which is imperative for our industry to move forward.

First Pass - Chicken or Egg?

It is well known in the industry that energy analysis used to improve design has the greatest impact at the very earliest stages of a project.
One must add to this that the costs associated with making changes is least also at the earliest stages of the project. *

But the effort to push energy analysis to the front of the project has run into a couple of hurdles:

1) The analysis software in use may not be fully integrated with the design tools, which are often still a pencil and paper. The good news here is that the software industry is working very hard to improve interoperability all of the time.

2) The other hurdle is the amount of assumptions needed to begin an energy model. The accuracy of the simulation is improved by reducing assumptions, by designing the building in detail much earlier. By the time your details are defined your project is usually far enough along that the scheme can't change and the analysis can only have a minimal impact on the design process. **

Another Approach:
We try to avoid these problems associated with assumptions by focusing on the variables we have the greatest control over that enter into the building energy equation.

Thermal balance occurs when the sum of all the different types of heat flow into and out of a building is zero. That is, the building is losing as much heat as it gains so it can be said to be in equilibrium.
Thus:

Qc - Conduction Gains
Qv - Ventilation Gains
Qs - Solar Gains
Qi - Internal Gains
Qe - Evaporative Loss

To remain in thermal equilibrium our HVAC system kicks in gear and is inversely equal to the sum of the gains.

For our projects in hot climates we only have two gains which significantly impact design that we are able to modify during an investigation modelling period. Qs which includes solar heat gain through windows is often our greatest load. The other big one is the heat from lights (Qi) for spaces not utilizing daylighting. ***

Its very easy for us to take a project in a hot climate, forget about all of these other building assumptions and just start working to minimize solar heat gain through windows while maintaining adequate daylight. Later, when we have enough building assumptions to produce an accurate energy model, our design will be in much better shape than if we had held off on the analysis.

But in a hot climate it can become more complicated when taking into account peak loads. The largest cooling loads generally occur late in summer in the afternoon, and the strategy to minimize peak loads sometime works against the strategy to minimize total gains. Knowing closely when the peak occurs can influence wall orientation, shading strategies and daylighting strategies on the west facade. One should rely on a full thermal model to get as close as you can to the time of the peak load to effectively work to reduce it. ***

Even more complicated than this are buildings with both heating and cooling loads for which we will try to minimize solar gains in one season while maximizing them in another (while ensuring that our solar design decisions work with our daylighting strategy). ****

If the designer can utilize solar analysis during the concept stage the building will be much improved by the time accurate energy modeling can enter the process. But to accurately design for solar optimization in moderate and cold climates they must make assumptions about the hours of the day and the months of the year for which there will be heating and cooling loads.

To find the heating and cooling range we probably need one of three things:
1) Expert guidance from a local engineer.
2)"Target Finder" type information that includes monthly loads for heating and cooling.
3) Perhaps a first pass at an energy model before there even is a design. The Egg before the Chicken. A first pass can be done with any reliable analysis software, verified by an engineer familiar with both the software and the building type and location. This analysis could be done using simple boxes, but it would be great to see the architect and engineer jointly develop generic building "type" models, easily dropped into any climate for the first pass at understanding basic loads associated with type and location.


There is a quote about knowing your enemy, but I'd rather focus on enlightened designing, utilizing both technology and one's conscience to design and produce buildings that really work well. To this effect how can we improve upon our process?

Image Reference:
* ASHRAEs 2003 Green Guide with vertical axis notes added for clarity by Alex Hirsig**

**Hirsig, Alex. "Design by Simulation: Building Performance Modeling by Architects in the Conceptual Design Process." Masters Thesis, Design Studies: Design and Technology Concentration, Harvard Universtiy Graduate School of Design, 2008

***The ASHRAE Guide for Buildings in Hot and Humid Climates, 2008

**** Bedington Zero by Bill Dunster Architects