Low-energy design: two views - Kieran Timberlake
Stephen Kieran and James Timberlake argue for technology as a key generator of sustainable design
The application of technology in pursuit of sustainability is tense and uneasy. Some blame technology for our current predicament: ozone depletion, rising sea levels, loss of habitat and a host of other threats to our existence. Others believe technology is the answer. Faced with these polarising viewpoints, it is tempting to turn back to a time when architecture directly reflected the natural energy economies afforded by sun, wind and water. But we cannot revert to the comfort of a known past.
As architects, we must apply technology to focus on the scales at which we operate. Technology is not going away. We must revisit the intelligence of craft-based vernacular form, extract the relevant intuitive approaches as a baseline and bolster them with technology. A return to good passive principles based on regional climates and vernacular knowledge is a start, but we need to do more to achieve nuanced and incremental performance enhancements. As we stated in our recent book Inquiry (2011), the ‘ethical obligation to perform [is] a central generator of architectural form’. To add to our intuition we need to look closer at more specific and refined scales of use and inhabitation to gain comfort and performance enhancements. It is here that technology can turn its maligned role on its head through the application of both hardware and software.
As architects, we must apply technology to focus on the scales at which we operate
In the hardware realm, we have developed multifunctioning walls that employ technologies to capture desired energy (solar and wind) and reject unwanted energy (heat and ultraviolet rays). For example, facades on our Yale University Sculpture Building are tuned to building orientation, using a combination of highly insulated glass, aerogel-filled translucent panels to admit daylight and solar shading to reduce solar gain. The translucent and transparent building envelope has a very high insulating value and a unified aesthetic to which nothing can be added or taken away. At Brockman Hall for Physics at Rice University, an energy intensive programme and humid climate were offset through fundamental decisions of building orientation and a series of nuanced facades to moderate negative climatic influences, while maintaining the precise indoor light, temperature, and humidity required for the highly sensitive experiments hosted within.
Promising new streams of research can now turn entire buildings into energy producers.
Our own work in this realm, beginning with SmartWrap, displayed at New York’s Cooper-Hewitt National Design Museum in 2003, speculated on the use of deposition printed organic photovoltaics (OPV) and organic light emitting diodes (OLED) onto thin polyethylene terephthalate (PET) layers to create a lightweight, energy gathering, mass customisable building envelope. This research was applied on a larger scale using thin-film PV technology at Cellophane House, and will continue its development in the outer envelope for London Embassy. However, many new sustainable buildings today reveal a tendency towards more and more hardware, based on the belief that hardware alone is going to get us out of this predicament.
What we also need to focus on is a new kind of software. Most environmental software is analytic rather than synthetic, incapable of influencing form before the parameters of design are fully established. We need software that provides information sooner and makes it visually accessible, so we can mould form around verified performance at the micro-scale of a particular site and distinct program. We are currently developing a suite of digital tools that provide increasingly precise data at ever smaller scales, depicted in a way that is useful at the earliest stages of design. Some are highly technical and use both hardware and software to gain precise site-specific readings of temperature, illuminance, humidity and carbon dioxide levels.
Others are remarkably low-tech, such as a tool that translates CFD data from a specific space into a quantifiable and visual topographic model. This readily comprehensible information can be used early in the design process to adjust form and test it as we seek to optimise ventilation.
Another such tool calculates the environmental impact in the materials of a design, such as embodied energy, as a part of BIM workflow in real-time. Embodied energy is a huge part of the life cycle energy use of most structures, sometimes equaling 40 years of operational energy. However, projects are not modelled to a sufficient level of detail to account for all of the materials in a building, nor are components modelled to reflect actual material volume. Moreover, any assessment of environmental impact factors, such as global warming potential or chemicals of concern, requires that we establish more refined definitions of architectural products than would normally be expected, or desired, in BIM models. With this tool, the impact of embodied energy can be considered during formative design phases.
As architects we must innovate within the technological terrain that lies between us and engineers
Closing the loop of design and information, we deploy sensors to verify performance and calibrate predictive modelling versus actual field performance. While much attention is paid to the sustainability of new construction, there are even more existing buildings needing retrofits for energy and other efficiencies. Existing buildings present a rare opportunity to study the passive thermal performance of an unconditioned, unoccupied building. We are presently using sensors to measure the microclimatic conditions found on multiple orientations of a building’s exterior, using the information as a data input for energy and thermal models. Misalignments between form and prediction suggest topics for investigation and improvement.
As architects we must innovate within the technological terrain that lies between us and engineers. We can no longer wait for science to simply verify intuition. We need easily comprehensible, democratised software tools to allow science to once again inform the art of architecture from its earliest conception.
Each increment of design insight, innovation and control afforded by this ever increasing array of easily used and understood iterative design tools may well transform energy outcomes, as much or more than the high performance hardware. In order to meet current and future planetary challenges, research, analysis and data must sit on an equal footing with design intuition. Rapidly emerging information technology can inform the art of sustainable design, leading to aesthetics informed by performance.
In today’s political terms, positions are often staked out in stark contrasts: either/or is far more marketable than any nuanced position that confronts present realities.
Debating contrary positions often results in paralysis, rather than working toward real solutions that lie in the murky and grey realities between those poles. Those who advocate solely for more technology are just as deluded as those who seek a return to the regional vernaculars of the pre-energy economy. It is the fusion of science and technology with art and intuition that offers the most effective passage forward.