Many a great design may have been scribbled on the back of an envelope, but these days smart thinking more often takes shape on a computer. Warren McLaren does a brief roundup of some of the green digital software tools available for designers, architects and engineers to conjure up a brighter world.
Ecotect
Ecotect was originally designed by Dr. Andrew Marsh whilst at the University of Western Australia. In 2008, AutoDesk, the company behind the first CAD (computer aided design) program to run on personal computers, AutoCAD, acquired EcoTect software. A building analysis tool, Ecotect allows architects and engineers to measure a building’s performance criteria like solar, thermal, shading, lighting and airflow. Ecotect provides analysis very early on in the design process and does not require a completed building design to furnish performance data. This affords architects an ability to design more energy efficient buildings from the get-go, reducing not only project development cost, but both building operational costs. Ecotect also allows CAD designs to be imported via a variety of formats, such as DXF, OBJ or 3DS, providing quick virtual assessment of daylighting, shadowing, solar gain and thermal comfort at any time of day. Ecotect has a web-based companion, Green Building Studio, which adds carbon neutrality analysis to the package.
Google SketchUp
The surprisingly powerful SketchUp is available as a free download from Google. For those requiring more, there’s SketchUp Pro, which costs about US$500 (still modest compared to other CAD programs). Oddly, coming from Google, SketchUp is not a web-based application but runs on either later versions of Windows or Macintosh OS X. The US’ National Renewable Energy Laboratory (NREL) have added to this gratis software bonanza by also offering its Open Studio tool, which combines EnergyPlus, a software program for analysing energy use in buildings. Open Studio is a free plug-in for SketchUp. Heating, ventilation and air-conditioning loads can be modelled, as well as lighting and water systems. Open Studio enables buildings created in SketchUp to be assessed for their thermal load by simulating the sun's movement during the day for a whole year to determine if windows have been effectively shaded.
AusLCI
The problem with much life cycle assessment (LCA) software is that it relies on data from Europe or North America, which isn’t always applicable to an Australian context. A decade or so ago this was rectified via locally developed pioneering products such BHP’s LISA (LCA in Sustainable Architecture) and the NSW’s Department of Public Works’ LCAid. These projects have languished so there remains a strong need for a local Australian database ranking building products on their whole of life environmental impact. The Building Products Innovation Council (BPIC) has thus teamed with CSIRO and Australian Life Cycle Assessment Society to develop such a library. Known as the Australian Life Cycle Inventory (AusLCI), it is scheduled for release later in 2010. BPIC’s 10 major building material associations have been working towards a consensus on LCA methodology, while CSIRO is designing a web database designed to integrate with common CAD software.
AccuRate
The Australian National House Energy Rating Scheme (NatHERS) is computer simulation software designed by CSIRO for rating home energy use under Australian conditions. Introduced in 2006 as the second generation of NatHERS came its successor, AccuRate. The software is used to provide energy star ratings for residential dwellings by modelling the annual heating and cooling requirements of a house design. AccuRate is considered to have improved on NatHERS, particularly with regard to consideration of natural ventilation, roof and sub-floor spaces, skylights, as well as matching climate data from the 69 different zones used by the Bureau of Meteorology (compared to 28 in the earlier version). Up to 50 living spaces within a home may be modelled by the program. The same calculation engine inherent in AccuRate is also to be found in the two other Australian energy rating programs — FirstRate 5 and BERS (Building Energy Rating System) Pro. [The accuracy of these programs was recently called into question following an investigation by the Housing Industry Association and Master Builders Australia].
SimaPro
Created by PRé Consultants in the Netherlands, SimaPro is one of the most respected life cycle assessment software tools around, having been around for 20 years and used by practitioners in over 60 countries. It is not dedicated architecture design software, but rather a whole-of-life-cycle measurement tool. SimaPro uses large material database inventories to describe the balance of the environmental impact of material inputs with product outputs. In short, it measures what goes into a product’s life cycle and what comes out. It could provide, for example, a floor covering manufacturer assistance in choosing whether recyclable polyester is an environmentally preferable carpet material to renewable wool over the useful life of that flooring. In Australia, SimaPro’s data set is derived from the Australasian Unit Process LCI library, which comprises data collated over 12 years by various Australian environment agencies.
GaBi 4
Like SimaPro, GaBi has been around for a couple of decades, although in this instance it hails from Germany. Based around a material’s inventory of over 4,000 life cycle inventory profiles, GaBi software can help designers identify the environmental performance of proposed materials and processes, how design decisions will reduce or increase carbon dioxide emissions, as well as comparing social and financial aspects of intended designs. The range of impact potentials that can be assessed is extensive, ranging across a broad spread, including global warming potential, eutrophication and ozone layer depletion. Data can be exported into Excel, so results of analysis can be shared with colleagues not using the GaBi software. Within GaBi, information can be presented graphically in a wide variety of charts and flow diagrams, with immediate changes visible by enacting ‘what-if’ scenarios for products and processes.
XFrog
As something a little different from the usual LCA and energy assessment programs, we’ve opted to include a couple of programs a little more quirky. XFrog Plants is one such example. It offers 1,300 botanically accurate plant models that can be used in 3D CAD-style software. Such plants can give greater realism to often bland computer rendered illustrations and models. Its plant inventory takes architectural and landscape rendering to a whole new realm. For example, its Oceania sets include the likes of Coastal Wattle, Lemon Bottlebrush, Spotted Gum, Australian Tea Tree, Bread Palm, Blue Gum, Australian Cabbage Palm and Flame Tree in all nine variations of 60 individual species. And with many Australian home owners taking up backyard gardening, XFrog also offers a large array of life-like vegetables in various stages of growth, from onions to broccoli and asparagus to zucchini.
Airpak
Ansys Airpak is a computer aided engineering (CAE) tool. It works by modelling computational fluid dynamics (CFD), or put more simply, airflow, and how this can impact on the passage of contaminants through building. It also models how airflow affects building occupants’ thermal comfort. Ansys Airpak can import CAD drawings in IGES or DWG/DXF format so that radiant temperature, relative humidity, air turbulence and velocity can be mapped with a structure. The effectiveness of chilled beam placement can be simulated, as can air-conditioning and natural ventilation. Varying designs of air-conditioning vents can be modelled, the flow rate of fans adjusted and thermal imagery can visually indicate which occupants are likely to be too hot or cold. Such software ensures optimised placement of energy intensive HVAC systems. Airpak enabled Cornell University to take top honours in the Comfort Zone section and Second overall in the US Solar Decathlon energy efficient housing competition.
LCA Calculator
Some green design software requires a significant degree of computer savvy. LCA Calculator does not. Rather than alienating neophyte life cycle assessment (LCA) users with an expensive, highly complicated LCA tool, the British-based Industrial Design Consultancy (IDC) has refined the process right down. LCA Calculator is a free, online tool ideal for designers wanting to rapidly get an idea of what environmental impacts a proposed design might incur. It asks a small number of questions before generating mini reports on your product’s potential lifetime energy consumption and carbon dioxide emissions. The results reflect inputs you submit regarding the four basic stages of a product’s lifecycle: extraction and manufacture; transport; use; and disposal. You can nominate up to five product materials from over 30 options and three packaging materials from over 20 alternatives, whilst indicating four modes of freight between eight worldwide regions. A worthy starting point if you’re new to green design.
Sustainable Minds
Sustainable Minds is yet another web-based life cycle assessment (LCA) tool, though a great deal more comprehensive than the free alternative we mentioned elsewhere. Sustainable Minds has merged Eco Design methodologies with LCA processes. For, as they point out, 75 per cent of a product’s manufacturing cost is often determined at the concept phase. Sustainable Minds establishes a reference product so you have a benchmark against which you can compare umpteen greener design options, like material choices, design for disassembly, and so on. Data input is streamlined with the ability to import a product’s bill of materials from existing CAD specifications. It then becomes a simple process of comparing various greener design alternatives to the original reference product to see which has the desired result required. Sustainable Minds generates graphically expressive product impacts that go beyond the usual carbon emissions to include issues like ozone depletion, water eutrophication, human carcinogens and more.
