Why the Design & Build Community Should Focus on Embodied Energy
With climate change becoming an ever more pressing problem, every industry has a responsibility to take action. Brent Trenga, LEED AP BD+C, WELL AP, Building Technology Director for Kingspan Insulated Panels North America, explains how the design and build community can play a role, by reducing embodied energy in the design framework
Snøhetta’s Powerhouse Brattørkaia is a striking example of a project that includes embodied energy in its design framework. Images courtesy of Snøhetta
LEED AP BD+C, WELL AP, Building Technology Director for Kingspan Insulated Panels North America
As the Earth’s average temperature continues to rise, so do efforts to combat the effects of climate change. These efforts include the Paris Climate Agreement, which hopes to limit global mean temperature rise to 1.5°C above pre-industrial levels.
This is an ambitious but attainable goal if each industry does its part. In the design and build community, reducing embodied energy is a critical component in the fight against climate change.
Reducing embodied energy to lessen the overall impact of the built environment becomes more urgent when you consider that today the proportion of embodied energy in buildings has increased to more than 40% of energy consumption.
According to a report from the Global Alliance for Buildings and Construction, the building sector growth rate over the next 40 years is expected to produce more than 736 billion square feet of new construction – adding the equivalent of the city of Paris to the planet each week.
Reducing embodied energy in the design framework
As we look at the intersection of architecture and the environment, there is a need to factor in embodied energy in the context of viewing the production of a building as an act of energy expenditure.
Architects should focus on designing buildings that extend beyond the boundaries of their walls and facades, reducing embodied energy in their design framework by accounting for many invisible-yet-essential aspects of the built environment, including embodied carbon, embodied water, and embodied labor.
A great example of this is being done in Norway, as the country enters a new era of climate-conscious architecture. One of the projects that illustrates how we can reduce embodied energy is the Powerhouse Brattørkaia, in the city of Trondheim.
“ Architects should focus on designing buildings that extend beyond the boundaries of their walls and facades, reducing embodied energy in their design framework by accounting for many invisible-yet-essential aspects of the built environment. ”
Brattørkaia is an eight-story office building that produces 485,000kWh of electricity annually (by comparison, the average US home uses about 10,000 kWh per year). As a mini power plant that can supply electricity to Norway’s publicly-owned grid, Brattørkaia’s surplus energy also compensates for the energy used to produce its building materials.
Snøhetta architect Jette Hopp told The Atlantic, “That is unique; prevailing definitions for energy-positive buildings don’t include materials’ embodied energy.”
Hopp also added that “we tried to give things multiple functions, and that directly leads to less embodied energy since we don’t have to double or triple up systems”.
“That’s in the smart thinking—but you need to have the knowledge of all the different layers of infrastructure works in order to find synergies.”
In separate books on the topic of embodied energy, Columbia’s David Benjamin and Harvard’s Kiel Moe advance the opinion that the way we design today results in buildings that consume more energy than ever before - with serious consequences. They also indicate that architects egregiously approach buildings as isolated objects, when they are instead moving parts in a far-reaching, enduring, and complex network.
In the fight against climate change, designing for energy efficiency is low hanging fruit; it’s time to focus more on designing with embodied energy in mind in order to make a real difference.
Image credit: Prof. Volker Staab/ © Staab Architekten
Embodied energy in building materials
To create low-carbon buildings, we need to choose low-carbon building materials. But right now, choosing these materials is challenging because the data is not readily available and what we do have lacks transparency to ensure it’s accurate.
Microsoft is the first large corporate user of the Embodied Carbon Calculator for Construction (EC3) to track the carbon emissions of raw building materials, introduced by Skanska and supported by the University of Washington Carbon Leadership Forum, Interface and C-Change Labs.
“We’ll use this in our new campus remodel. Our early estimates are that a low-carbon building in Seattle has approximately half the carbon emissions of an average building, so this could have a substantial impact on reducing carbon emissions in our remodel and eventually the entire built environment,” wrote Lucas Joppa, Chief Environmental Officer for Microsoft, in a corporate blog.
“ The drive toward reducing embodied energy in the built environment should also include a movement to make changes at the supply chain level. ”
Every building is a complex combination of many processed materials, each of which contributes to the building's total embodied energy. In looking at reducing embodied energy in the design process, it is important to keep in mind that more processed materials will generally have higher embodied energy.
Some of the factors that contribute to a material’s embodied energy include:
- The distance needed to transport materials; local sourcing results in lower embodied energy.
- Amount of raw materials used.
- Complexity of the manufacturing process; the more complex the process, the more energy intensive it is.
- Recycling potential.
- Efficient building design.
Most life cycle assessments (LCA) show that the majority of embodied energy comes from the supply chain. As such, the drive toward reducing embodied energy in the built environment should also include a movement to make changes at the supply chain level, encouraging producers of steel, concrete and other materials to continue to shift towards more sustainable practices.
It makes sense to look for options that minimise the initial energy investment—the embodied energy—in the built environment. The design and build community can make a significant impact by selecting materials that have an LCA or an environmental product declaration, helping to impact climate change by making smarter, sustainable choices in the products they use.