What role do buildings play in the energy transition?
February 10, 2021
The path to change starts with collaboration between the buildings and energy industries
When we talk about the energy transition, we must consider the whole picture. As much as we tend to gravitate toward the energy we produce, we must also consider the energy that we consume. How can we manage the energy consumption of our communities more efficiently? What industries can help us in our actions to reduce global greenhouse gas (GHG) emissions? And how can energy providers work with these industries to find opportunities for reducing energy consumption?
One industry that is at the forefront of this challenge is the buildings industry. Why? Because buildings are responsible for 39% of global energy-related carbon dioxide emissions. The architecture and engineering industry has realized that to successfully reach a carbon neutral future by 2050, we must drive this figure down¡ªpreferably sooner rather than later. In fact, a study by the Rocky Mountain Institute estimates that global buildings emissions must decrease by 50% by 2030. So, what can we do to effectively reduce these emissions? Let¡¯s start with the following three goals:
- Retrofit or upgrade existing buildings to be more energy efficient and adaptable to new uses.
- Decrease our dependency on energy generated by fossil fuel sources by designing our new buildings, and upgrading our existing buildings, to be 100% electric and powered by renewable energy.
- Improve the energy resiliency and health of our communities by collaborating with utility companies to create a more dynamic relationship between buildings and power grids.
Buildings account for a significant contribution towards global GHG emissions¡ªat almost 40%.
Making our buildings more efficient
While the number of verified net zero energy buildings being constructed is increasing, the pace is not fast enough. In fact, the New Buildings Institute national database of verified and emerging net zero buildings shows there are only 136 certified or verified net zero energy building projects across North America as of September 2020, with another 547 in progress.
In addition, we must shift from a focus on net zero energy to aiming for net zero carbon. That is, carbon neutral buildings that look not only at the units of energy consumed and offset but also the greenhouse gas emissions¡ªwhich include carbon¡ªassociated with their fuel sources. So, what can we as architects and engineers do to accelerate the percentage of buildings, both old and new, that are achieving net zero goals??
Heading forward, building developers and local utility providers need to work together in stride, finding ways to optimize energy efficiency and provide cleaner energy to the communities they serve.
Reducing emissions for new buildings
When it comes to new buildings, there are many methods¡ªold and new¡ªto reduce emissions and minimize a building¡¯s carbon footprint. These are the top five ways to make your new building project more efficient:
- Passive load reduction: Passive strategies rely on building form, geometry, and architectural elements to reduce reliance on powered systems while remaining comfortable and operational. Some examples include orienting the building to benefit from daylight and natural ventilation, as well as selecting highly insulated wall and window assemblies to minimize heat loss or gain.
- Energy-efficient systems and controls: Integrate efficient HVAC, lighting, power, and energy recovery systems with smart controls. This allows a building to be more responsive to varying patterns in occupancy and use, as well as to identify issues in real time for faster response and resolution.
- Electrification: Design building systems to be 100% electric, avoiding the need for on-site fossil fuel combustion. This includes better supporting integration with on-site solar photovoltaics (PVs) and battery storage.
- On-site renewable energy and storage: Offset energy use with renewable energy sources, preferably on-site. Include battery storage to leverage the economic benefits of reducing peak loads. The key to innovation and financial success in the net zero equation is close coordination with local utility providers from day one.
- Long-term monitoring: Long-term monitoring of energy use is critical to ensuring a building is operating as efficiently as it was designed to. Smart controls and trained personnel are key to supporting identification of potential building issues before they become critical.
When it comes to new buildings, there are many methods¡ªold and new¡ªto reduce emissions and minimize a building¡¯s carbon footprint. (evolv1, Waterloo, Ontario).
Reducing emissions for existing buildings
While there may be fewer options when retrofitting existing buildings, there are still many ways to make them more efficient. These are the top five ways to make your existing building more energy efficient:
- Retro-commissioning: Retro-commissioning is the process of inspecting, testing, and adjusting existing building systems so they continue to meet expectations for the duration of their life cycle. Over time, occupancy patterns and the use of different spaces in a building may change. So, a periodic check-in of the building is key.
- Energy-efficient systems and controls: While you may not be able to replace or upgrade the systems in existing buildings, there are a number of smart controls that can be installed post-occupancy that result in greater efficiency in how a building is operated.
- Electrification: Consider a phased approach to replacing fossil-fuel equipment with electric alternatives. This can either be at the end of useful life for major equipment, or at the point where switching to electric-powered equipment¡ªoffset by on-site PVs¡ªis a positive return on investment. Engage an electrical engineer to assess if the building¡¯s electricity service feed capacity needs to be increased.
- On-site renewable energy and storage: If an existing building¡¯s roof structure cannot support rooftop PVs, identify a location on site for a solar carport. This is a structure covered in PVs that is large enough to provide shade and weather protection for parked vehicles. Not only is this a highly visible signal of an organization¡¯s commitment to clean energy and environmental stewardship but it benefits employees to have their vehicles shaded from sun or protected from snow and rain.
- Long-term monitoring: As with new buildings, long-term monitoring is essential to make sure the building is meeting the occupant¡¯s comfort and functional needs every day, through all seasons and changes.
For any building project, understanding the load profile is extremely important throughout the decision-making process. The load profile refers to the projected energy use of your building. What are the most critical loads? What are the most unique loads? This data is key to optimizing energy efficiency for a building, and therefore the associated carbon emissions.?
While there may be fewer options when retrofitting existing buildings, there are still many ways to make them more efficient. (University of Colorado Denver Business School, Denver, Colorado).?
Forming a strong, two-way relationship between buildings and the grid
One of the most important methods of reducing energy consumption for your building¡ªand for the surrounding community¡ªis by improving the relationship between your building and the local power grid. Before this was a one-way relationship, with buildings receiving energy from the grid. But now it¡¯s a two-way, mutually beneficial relationship. We call this grid citizenship.
Grid citizenship involves buildings with on-site renewables and battery storage redirecting energy back to the grid¡ªhence the two-way relationship. It is made possible through coordination and collaboration with local utility providers. Not only does this build positive relationships with the local community but it's critical for identifying utility rates, clean energy incentives, and demand response programs that support the economics of the energy transition.
Considering the utility representative as a member of the project team¡ªand engaging them early on¡ªcan have a positive impact on the long-term economics of the building. It is also important to understand how clean the grid is. Regions vary when it comes to the greenhouse gas intensity of the utility grid serving the building. So, that intensity can significantly impact decisions on the cleanest energy source for a building, as well as the role of on-site renewables, in meeting a carbon goal.
This chart highlights the GHG intensity of electricity generation in each province of Canada.
Thoughtful decisions for better buildings
As I said earlier, buildings account for a significant contribution towards global GHG emissions¡ªat almost 40%! If we hope to achieve the goals set by the Paris Climate Accord, the buildings industry must be part of the solution.
Heading forward, building developers and local utility providers need to work together in stride, finding ways to optimize energy efficiency and provide cleaner energy to the communities they serve. It is important to keep up to date with the current codes, regulations, and standards to achieve this. It is also key to understand where the codes are headed in the future¡ªthese will evolve and knowing them will keep you ahead of the game.?