Sources of Inspiration in the Search for Deep Energy Savings

It’s been said that the greenest building is the one already standing.  There’s a lot of truth in that when you consider the embodied energy of building materials and, with luck, a cultivated sense of place.  At least in the case of historic structures, there may be inherent, environmentally sensitive attributes—and that says nothing of the quality and provenance of historic materials. While many existing buildings may not perform at the level we’d like to see in terms of energy efficiency, many have the potential to do so. Deep energy retrofits and renovations are now helping to ensure that existing buildings have a future as pinnacles of green design. What better way to accelerate deep energy savings projects than to look for clues in existing success stories?

Search for Deep Energy Savings

This summer NBI released a set of project profiles for nine existing building renovations and retrofits as part of ongoing work for NEEA’s regional Existing Building Renewal (EBR) initiative to accelerate commercial adoption of deep, integrated energy-efficient retrofits. NBI’s foundation work on deep savings in existing buildings for Doris Duke and Kresge also contributed to the project. The project profiles and a summary Meta report, A Search for Deep Energy Savings, were compiled to shed light on common technologies and practices to accelerate the commercial adoption of deep retrofits on the way to net-zero. Each project resulted in an energy savings improvement of 30% or more than the national average for similar office buildings, with seven having savings of 50% or more. Eight of the nine projects were deep energy renovations (three of which were historic renovations) with one a simple equipment retrofit project. Some of these buildings at a transition of use provided the opportunity to go for the greatest efficiency improvements. It’s an impressive set of projects, featuring energy efficiency measures ranging from daylighting features and natural ventilation to controls, renewables and commissioning. Together, they achieved a total of 13 LEED certifications in 4 categories (all but one at the platinum level) in addition to other awards and recognitions. Seven of the nine saved 50% more energy than the Commercial Buildings Energy Consumption Survey (CBECS) national average (2003 survey),  and have an average Energy Use Intensity (EUI ) of just 39 kBtu/sf/yr. In short, all are impressively low-energy buildings with proven energy performance. Plus, project representatives cited market benefits like increased occupancy rates (from 68-96% in one case), retention rates, and a willingness to pay a premium on rent. So, how do we take inspiration from these stories of success and package them for a wider audience?

Accelerating market adoption

These project profiles represent some of the highest performing deep energy renovations and retrofits to date—their energy performance numbers reflect this. But what made them successful? We know the end performance is there—but what about the process? It’s the lessons learned from these kinds of projects that organizations like NEEA will use to inform market transformation. So back to that question: what went into making these projects successful?  For one, many had a team of experienced, energy-minded professionals behind them. In only one instance were the architect, engineers and contractors not on board with low-energy goals from the outset. This was no accident on the part of the owners (buildings were split evenly by owner type: 1) private investor 2) owner occupied—green architect/construction firms 3) owner occupied—non-profits), who recognized that energy improvements were an innate, rather than optional part of their building upgrade. Three of the projects were designed by and for green firms, so the motivation was there with little question of the long-term return on investment. Additionally, any tenant wanting a “green” space would likely embrace tenant improvement or behavioral guidelines, further ensuring actual energy performance. Also, while cost was still something of a challenge in these projects—as with nearly any renovation or improvement project—it was by no means a primary barrier. Generally, funding included some combination of grants or tax credits, and for this set included donation-based and private investor funding.  However renovations were still completed within standard budget ranges for the level of work. In some instances certain energy efficiency measures were passed over for more economical (and sometimes more creative) solutions, but the end result was the same: 30%+ energy savings. The Meta Report suggests there really is no one-size-fits-all approach to achieving deep savings. What it takes is a combination of intention, creativity and flexibility. However, the report points to several concepts that can be appropriately applied to nearly any renovation or retrofit project that pushes the energy envelope:

  • Integrated design, multiple measures and ongoing monitoring are more impactful than any single technology.
  • The consistent use of controls (lighting, HVAC, CO2, and whole building)
  • The use of readily available technologies combined with progressive measures
  • Behavioral measures, such as tenant improvement plans or tenant level metering

This inspiring set of project profiles is a shining example of the potential for implementing deep savings in existing buildings. They also benefitted from a team that understood the value of pursuing green design and deep energy savings, had vision, knew how to maximize the energy-related funding available, could track results and conduct commissioning, and knew how to market the “green.” So, what does it mean for the wider audience and potential market of building owners, managers and others who don’t have these advantages? The trick will be to define this path to guide and motivate a broader audience, thereby facilitating the renovation or retrofit process. It will involve making the case to all parties involved and communicating the long-term value. Ultimately it won’t be about selling the “green,” but greening the norm.