An international team led by Erin Cooper, Research Analyst for EMBARQ, won The Fred Burggraf Award for excellence in transportation research by researchers 35 years of age or younger. Photo by the World Resources Institute.

What led you and your team to research this topic?

We started working on this topic because even though there is a lot of information about alternative fuels and different types of vehicles, it is really hard for non-emissions experts to understand what it all means. Because of the way buses are often procured, the cost of these new technologies is really important. The operators want to know the full cost of a bus prior to purchasing the bus, and they also want to know that they are making effective emissions reductions.

We wanted to get a better understanding of the vehicle emissions from different types of buses—so our research looks at all the same kind of bus, 12-meter long buses, but studies different fuels and different types of technologies for reducing their emissions.

There is a range of factors that determine bus emissions. It’s a challenge to simplify that data in a way people can understand, and then make sense of, and make a policy or decision from.

You mentioned that the difficulty right now is that non-emissions experts have trouble making sense of complex emissions data. Who is making the policy decisions and purchasing the buses?

A lot of times a transit agency is making these decisions – sometimes it is higher level agencies, but a lot of times transit agencies are very interested in on-road emissions testing. There is a real concern from these agencies that the theoretically “best bus” on paper might not work very well in practice.

And there are certain cases where fuels that work well in theory can have  problems when they’re put into practice or are very expensive. Transit agencies have to deal with those issues as they come up. There’s always that issue when bringing new technologies into practice—you don’t know what is going to happen.

You mention theory versus practice- is this related to your decision to use real bus testing? Can you explain the difference between “on-road testing” and drive cycle testing?

In on-road testing they take the bus out on the street and collect emissions data while driving on a typical route.

When they do the emissions testing used to certify buses, they use a few different types of drive cycles. They do try to get the full range, but there is concern that this doesn’t capture all the different scenarios. Sometimes agencies will develop their own drive cycle that shows their unique pattern of stopping and starting within their cities.

Different drive cycles do impact certain types of emissions. I have seen some studies where they have modeled emissions in different environments, certain fuels look really good in an urban context, where there is a lot of stopping and starting, and other fuels have lower emissions when operating at a more constant speed. So there is a difference. Drive cycles are important.

That’s why we wanted to get data from as much real testing as possible, or tests where they were looking at a certain city rather than just using the general drive cycles.

What was it like bringing an international team together? I’d imagine you all had different working habits and approaches to research. What were the difficulties or advantages of working with a team like that?

Actually, our donor for this project, FedEx, did a great thing to help us start the project. Because we are an international team they brought us all together at their Memphis headquarters so we were all able to meet each other and spend a week together learning about the topic a little bit more from FedEx’s perspective, where they told us about their own experience with heavy duty vehicles and meeting stringent emissions standards in California. But they did not influence our research.

Having the team come together was very useful to establishing the relationships that you need to do these types of projects. Other than that, it is a challenge to be working so closely on a project with people who are so far away all the time, in many different time zones. It required a lot of dedication from the team to try to see everything through. It is much easier to go ask someone a question, or to explain data if you are sitting in the same room. If you’re remote it requires a lot more effort. That was on the whole team, everyone made the effort to make sure we were communicating.

Perhaps a reflection of your international team, your paper has a strong international focus. Why did you and the team choose to focus on developing countries, where data seems scarce?

We tried very hard to get a lot of data from developing countries. There was not a whole lot to get when we first started. We’ve since found more. It is important because developing countries have different fuel qualities and different technologies available on their buses. So the results are slightly different, or in some cases very different, from the results you would find in the U.S. or Europe where the fuel qualities are better, with lower sulfur content in the diesel.

When you look at the U.S. and European data, it just doesn’t translate to the other countries immediately. And that’s the main effort here — is to translate the existing research into something that can be used in other places.

You and your team won this award for work by researchers under 35. How did you get into doing research, and get so far so fast?

Working on research itself is important. Building your knowledge in how to do research as well as in your subject area – It just takes time. I’ve had a lot of good training along the way… various internships and mentors in different subject areas over the years, my professor Cornelius at Cal Poly who I worked with for over three years, and a lot of support from my EMBARQ team (Aileen Carrigan, Dario Hidalgo, and Jorge Macias) as well as the EMBARQ network… a lot of good training. Becoming a good researcher is not something that happens quickly. So for me this is really not that fast at all.

What’s next?

The next piece of our project is coming soon! We are now working on specific case studies for Mexico, India, and Brazil. We’re looking at bus lifecycle costs and lifecycle emissions – that includes emissions from producing the fuel, etc. I think from there we will have some more clear recommendations. In this current paper, it’s more general results. So that piece is exciting – that’s in the works.

I think another reason that this whole project is successful is because we are at the World Resources Institute, so we have at hand much broader environmental resources. We have groups like the GHG Protocol here that makes us think more broadly about lifecycle emissions. But because we also have a transport side, we’re looking at the cost of vehicles too.

So I think it’s a good representative project of EMBARQ at the World Resources Institute.