Modeling Green Environments
Simon Wild, the senior environmental engineer at Cundall Johnston and Partners, explains that Genesys becomes involved in a project at its onset. "The architect will ask us for help at the concept stage on issues surrounding the internal and external environment of the building."
Adds Fogarty: "Because we have done this a number of times, we have built up an extensive knowledge base. We can provide feedback on any aspect of a design within a few days, therefore helping to progress the conceptual stage faster."
Based on the information provided by the architect and their own research, Genesys produces several variations on the concept design and helps architects decide where to focus their design attention for maximum benefit.
In what has become a specialist market, Genesys's services range from analyzing shading in facade development to energy auditing of completed buildings.
This diversity of consulting work means they make use of a variety of computer packages, some of which they develop in house. "Although we do buy off the shelf, says Fogarty, "we often are the guinea pigs for some of the newer packages. We are therefore able to feed back our ideas to the developers."
The Wellcome Trust Building
The company recently worked with Michael Hopkins and Partners on the facade design of the new Wellcome Trust building in north London, scheduled for completion in 2004. The design is a 10-story building with a lower six-story frontage. The client wanted a "green" energy-efficient building with an innovative design.
The facade of a building represents the architect's signature, but it is also a source of light and a thermal barrier. Its performance is critical to the efficiency of the energy used.
The designer has a number of systems to choose from including external shading methods, various glass technologies, and double-skin facades. What is the best solution to a given problem? Genesys models the outcome for all of the options; then it is up to the architect and client to match benefits and costs.
Genesys was asked to provide input into the design of the internal atrium and the glazing system. One of the computer modeling systems Genesys used was ECO 1. Developed in house, this is a simple wireframe 3D modeler used to calculate solar penetration and predict the performance of the proposed shading systems.
The firm also used computational fluid dynamics (CFD) to determine the potential air movement and temperature distribution of the atrium. Genesys modeled air flow and heat exchange on a micro level using the Phoenics package by CHAM.
Genesys uses CFD primarily to look at factors affecting human comfort: areas of overheating and stagnation in natural ventilation and air conditioning designs. They can identify areas with potentially high heat gains, whether through physical activity or from other heat sources.
In the Wellcome Trust building, the CFD analysis predicted a heat buildup at the top of the curved atrium. In the end, they proposed a double-louver system that would reduce glare and keep the heat levels to within the acceptable comfort factors.
To provide insight into the thermal responses of a building throughout the year, Genesys conducts a dynamic thermal analysis. They use TAS software produced by Environmental Design Solutions Limited (EDSL) to visualize the relationships of such aspects as air temperature, work activity, and levels of clothing to the potential energy performance of the design.
Genesys uses TAS to simulate natural ventilation, facade comparison, comfort analysis, energy targeting, and life cycle costing. They provided TAS thermal modeling information to architect Fletcher Priest for Vodafone's World Headquarters near Newbury in the southern English county, Berkshire. The new £120 million headquarters will provide office accommodation for approximately 3000 staff in seven buildings totaling approximately 550,000 square feet (51,000 square meters).
The aim has been to ensure that the buildings are energy efficient, have good daylighting to reduce the demand for electric lights, and take positive steps to control water resources.
Genesys also uses THERM, a window frame analysis program developed by Lawrence Berkeley National Laboratory
to determine heat transfer through windows.
A building facade is not only the architect's signature and the thermal barrier between inside and outside, it is also the medium that determines interior natural lighting.
Radiance software developed by Lawrence Berkeley National Laboratory provides information about the performance of internal and external lighting systems, identifying glare sources, luminance values, and visual comfort analysis.
Genesys uses Radiance to predict glare, solar penetration, and the effect of innovative lighting systems. Providing a comfortable, daylit environment has the added benefit of reducing energy consumption. Up to 40 percent of a building's annual energy use is in electric lighting.
Here comes the sun
Sun penetration and solar access are important factors of energy efficient design. A combination of ECO 1 and the Radiance software provides graphical representations of the shading performance and interior lighting contours indicating the efficiency of windows.
The packages enable the consultants to assess the shading elements of any building along with the solar transmission and reflection analysis. This evaluation helps the architect visualize how a building shades its neighbors throughout the year.
All of the elements of a building are interrelated. Likewise, the software systems that Genesys uses provide the potential for integrated environmental results. For example, human comfort is affected by air movement, solar performance, heat loss, sound transmission, and lighting in varying degrees.
"We can also identify opportunities for 'future proofing' a building," says Fogarty. For example, they can anticipate new materials currently in development or plan for the location of photovoltaic panels when they become commercially feasible in the future.
Alan Fogarty concludes: "We can provide some answers, but because environment-related design is so extensive and innovative in its use, often as not, no one really knows what the questions should be." Nevertheless, since its inception, the firm has become inundated with work.
Don Barker is a freelance writer and photographer in London, UK, who has lived and worked in Europe, Australia, Thailand, Sri Lanka, Hong Kong, and Singapore.