Arc provides a score for the operational performance of spaces, buildings, and places based off of five indicators. These indicators include a Transportation Score, which is a 0-to-100 measurement of greenhouse gases emitted in an occupant’s journey to work. This score relies on data self-reported by occupants, and it is independent of location.
This means that a project in Singapore, with a robust public transit system, is scored the same way as a city in Texas with little to no public transit infrastructure. Does that make sense? What about a project in a small town with no bike lanes, and a project in Bogota, Colombia, a city with over 220 miles of bike paths?
Let’s start by considering the original rationale for this scoring concept. The idea was to offer green building projects a globally relevant way to recognize and understand transportation performance. For LEED, this meant focusing on greenhouse gas emissions — the most important LEED v4 system goal — and measuring actual travel behavior — not management actions. Moreover, the goal was to provide a consistent benchmark for use across multinational portfolios. The resulting Transportation Score allows companies and organizations responsible for places, spaces, and buildings to understand how their facilities “measure up” to other entities around the world. In order to make this comparison, what they measure must be similar. In other words, they must have a common metric for measurement.
With that in mind, the COVID-19 pandemic has changed virtually everything about how we interact with the built environment, especially in terms of transportation. In late March and April, many transitioned to working from home, leaving the majority of office buildings unoccupied, and public transit unused. The lack of occupancy within buildings affects transportation scoring, because Arc’s current methodology for transportation scoring is dependent on surveying occupants about their transportation behavior. I, along with my fellow Schneider Fellow, Shikha Srinivas, explored alternative transportation scoring methods involving location-based scoring methods, and diversity of Transit modes, found here and here, respectively.
During our initial exploration into location-based scoring metrics, we first analyzed over 800 Arc projects globally. Our process involved correlating Walk Score values from the WalkScore platform with Arc Transportation scores. After our initial analysis produced an r2 value of less than 0.1, we realized Walk Score data was not widely available or reliable for locations outside of the US and Canada. With that in mind, we refocused our research to involve around 300-400 projects in the US and Canada.
While focusing on the US and Canada made sense in that particular analysis, the broader scope is that LEED projects exist in more than 170 countries, and the Arc platform is used in 122 countries around the world. Consequently, any viable transportation indicator must be relevant to the US and internationally. The question then becomes, how do we ensure we evaluate projects in the same way, universally?
Your mind might immediately jump to the same metrics discussed above. If the projects are evaluated across the same metrics, then surely the score is accurate for that project, right? Wrong.
Performance-based, shared metrics — such as those provided in the Arc platform — provide a comprehensive measurement and evaluation of performance across indicators that is essential for global comparisons. That being said, location-based factors are also extremely important when comparing one project against each other, and should be considered in a performance analysis. USGBC emphasizes the importance of location, specifically pertaining to natural context, infrastructural context and the social context of a place. In order to benchmark projects against each other, there needs to be some evaluation and discussion of the characteristics of their in order to get an accurate understanding of where a project stands.
With these considerations in mind, let’s return to the issue of transportation scoring: Transportation itself is extremely variable from one country to another. For example, Arc provides a menu of commute mode options: bus, single occupancy vehicle, carpool, motorcycle, scooter, walk, bike, telecommute, subway/metro, and tram or streetcar.
In Europe, however, long distance trains might also be a realistic commute option that is not necessarily provided in a commuter survey, but could be considered in location-based public transit metrics. In India, 10-20 percent of daily motorized trips are taken in Auto-Rickshaws, another form of transit not included in the existing commute mode options.
Another example that demonstrates the importance of location-based metrics is the adoption and commitment to carbon neutral public transit in Sweden. If someone in Sweden takes the bus to work everyday, but the bus is likely to be electric and zero-carbon; hyperlocal factors that should, ideally, inform carbon-emissions calculations and occupant choices on the transportation survey.
So, the fundamental question here is how can Arc provide a practical, operational transportation score that simultaneously recognizes these factors and meets the need for a consistent, globally-applicable performance metric. There are no easy answers, but there are several places we can start. Arc can:
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Create more transparency and flexibility about how travel data are collected and scored. Transparency and flexibility will allow an organization to understand how they are being scored. This is especially important under unique circumstances like COVID-19.
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Explicitly score the components of transportation (e.g., mode choice, travel distance, and emissions intensity), instead of just scoring overall greenhouse gas emissions
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Consider providing both local and global transportation scores — this will help communicate leadership across scales and localities.
Shared, measured, performance-based metrics are an important and a valuable component when comparing and scoring projects, but how we are measuring is important too. Emphasizing the how allows us to consider factors in the occupant and project’s environment that are place-based, in addition to common metrics. Adopting both will ultimately lead to a much more localized and accurate indicator of green performance.