It is no longer just a matter of reducing CO₂ emissions: now the goal is to create an environmental benefit that allows more CO₂ to be removed from the atmosphere than is generated, in other words, Carbon Positive.
Carbon-positive status is achieved by generating more energy than is consumed by creating an energy surplus from renewable energy. Or also, that a company’s products generate more negative greenhouse gas emissions than positive ones, or that a building produces more energy than it needs and returns it to the grid (a photovoltaic self-consumption system).
The aim is to decarbonize by avoiding carbon emissions through renewable sources (wind, solar, hydroelectric) and to advance in the storage of renewable energy.
In addition, for companies, achieving the goal of a ‘carbon positive company’ means advantages such as lower operating costs and greater flexibility in terms of energy supply.
Studio Gang and Urban Villages designed the first carbon-positive hotel in the U.S.
After construction officially began on the Populus Hotel, its developer, Urban Villages, has already described it as “the first carbon-positive hotel” in the United States.
Opening itself to the city and to the Rocky Mountains beyond, Populus is designed to become an energetic new social center in downtown Denver. Located on a prominent corner site, the building greets the neighborhood equally on all three sides, welcoming visitors and residents and connecting Denver’s civic, arts, and commercial districts.
The Populus Hotel was designed by Studio Gang, American architecture and urban design practice that focus on sustainability. The distinctive window shapes are informed by studying the characteristic patterns found on Aspen trees (Populus tremuloides), which is why, on its white facade, the windows grow up to 9 meters high, changing size in response to the public and private spaces, assimilating to this tree, which, as it grows, shed its lower branches, leaving dark eye-shaped marks in the papery bark of its trunks.
The windows have been further detailed to function effectively in the Denver climate. On the exterior, the “caps” of each window extend outward according to solar orientation to shade the interior, improving the building’s energy efficiency. They also perfectly channel rainwater so that the facade maintains a cool appearance over time.
A green rooftop terrace planted with regional vegetation offers expansive views across the top of the building, providing a lush place to socialize and an attractive habitat for local wildlife and insects.
Although not a direct feature of the hotel, the developers said this initiative will “offset an embodied carbon footprint equivalent to nearly 500,000 gallons of gas and [remove] additional carbon dioxide from the atmosphere.”
“Not only will we plant more than 700,000 trees, but we are committed to continuing to plant more trees to offset the energy we consume each day after the hotel opens,” Buerge added, according to Dezeen Magazine.
During the development phase, the structure will minimize its carbon footprint by using low-carbon concrete mixes and materials with high recycled content, maximizing structural efficiency, using fewer finishing materials and minimizing waste, among other strategies. Populus’ ongoing operations will also be carbon positive, so the overall use of the hotel along with each guest’s stay will be offset beyond the embodied carbon in the building.
Although the structure sits on the busy site occupied by Colorado’s first gas station at 14th Street and Colfax Avenue, the hotel will become Denver’s first hotel without on-site parking, typically built with steel and reinforced concrete increasing carbon profiles. This strategy encourages the use of public transportation and demonstrates that on-site parking is not always necessary as cities evolve toward a more pedestrian-friendly environment.