One of the most recognizable features of skyscrapers—their thin, steel-and-glass-frames—often becomes an enemy of efficiency. These building’s sleek, striking curtain walls result in extra heat gain and excessive heating costs in cooler climates, meaning these modern structures can sometimes be energy hogs. Achieving energy efficiency in a high-rise often means designing to evade the sun, with facades strategically shaped to deflect the sun’s rays.
A new skyscraper concept being examined in Australia turns this design concept on its head by welcoming, not shading, the sun’s rays. The Sol Invictus, a proposed 60-story project in Melbourne, would feature a new form of cladding that doubles as solar panels, allowing the building to generate much of its own power. According to Peter Brook, director at the Australian firm Peddle Thorp, which developed the plan, this bold bet on new technology would turn the traditional curtain wall into a high-tech power generator.
"This concept would see the technology shaping a fundamental part of the architecture," says Brook. "Many designers engineer buildings to reduce their exposure to the sun. In this case, we’re doing the opposite."
The concept goes back about three years ago, when Peddle Thorp was investigating new solar panel technology from China that could be used on a building facade. One of the main issues with incorporating solar power and panels into a multi-story development is surface area; the amount of square footage needed to power a tall building would require a comically large roof or a huge field of panels on the ground, both of which are financially unfeasible. This new material changes the equation.
According to Brook, a typical roof installation on the Sol Invictus ("invincible sun") would result in 400 square meters (4,305 square feet) of panels. With the option to wrap them around the facade, the Peddle Thorp team can fit 3,500 square meters (37,673 square feet) of energy-generating solar cells. That’s enough to take care of roughly half the building’s annual energy needs, says Brook, and with rapidly developing battery technology, could eventually provide even more.
If the tower is built in Melbourne’s Southbank neighborhood—it has been submitted to the planning commission, and wouldn’t be complete for at least three to four years—it’s elegant oval shape will maximize sun exposure and improve power generation capacity. Wind turbines, LED lighting, and double-glazed glass will also help reduce the building’s environmental footprint. Everything from window height to its orientation on site was designed to welcome, rather than avoid, the sun, a fitting metaphor for a project that’s trying to rethink traditional concept of sustainable high-rise construction.
"It’ll be a bit of a revolution, as far as some parts of architecture are concerned, if we can achieve some of the goals that we’re setting," Brook says. "Buildings have the potential to go through a significant change in how they use energy. It’s a tragedy more ideas haven’t been pursued, but if we can break through some of these barriers, an enormous amount can be achieved."