Decreasing Operational Carbon
As soon as the final concrete is poured and the ultimate pane of glass is put in, sustainable structure turns into a query of day-to-day efficiency. On the Amazon HQ2 towers, this contains consuming about 24% much less power than similar-sized buildings. How? The workforce at ZGF took a whole-building view of all of the challenge’s parts, each in isolation and along with each other, to coax the very best efficiency from the towers.
As an example, the buildings’ glassy exteriors aren’t simply an aesthetic selection; they make the constructions extra power environment friendly. Brian Earle notes that, “One of many fascinating issues once you construct a constructing this massive is that the hundreds contained in the constructing develop into way more essential than the envelope efficiency (thermal management) of the constructing. We discovered that it was extra essential for us to scale back our power use for lighting than to have the next performing thermal envelope. The thermal efficiency and transparency of the glass actually helped us optimize power use in that sense.”
In different phrases, because of the excessive volume-to-surface-area ratio of those towers, rising daylighting was extra useful to general power efficiency than decreasing glazed areas for the sake of thermal management. This wasn’t an apparent conclusion; it required in-depth power modelling. Nonetheless, as Rebecca Pantschyschak defined, “ZGF loves doing this sort of calculation to verify we’re discovering the proper resolution for the surroundings.”
In fact, utilizing high-performance glass helped with this resolution. The glazing for these towers is Starphire Extremely-Clear® from Vitro Architectural glass with a Solarban® low-e coating on floor two. The low-iron substrate maximizes pure gentle circulate into the constructing whereas the low-e coating reduces undesirable warmth acquire. This helps to scale back the constructing’s general power consumption and shifts the design towards a completely glazed constructing envelope. It additionally introduced the challenge one step nearer to LEED® Platinum standing by contributing towards the Optimize power efficiency credit score.
Making this challenge power environment friendly required a whole-building perspective. By contemplating the glazing along with the construction’s general proportions and power calls for, ZGF was capable of cut back power consumption and design a really sustainable constructing envelope.