Decarbonizing Transportation: Two Examples Of Progress

In the US and in other developed countries, the transportation sector is one of the largest sources of greenhouse gas emissions. Electrification is being pursued as an alternative for many segments, but that is only as “green” as the grid from which that energy is drawn. There are major sub-sectors of transportation like air travel and long-haul trucking for which in isn’t a viable option to go electric. There are; however, innovations in process that can further the decarbonization of aviation and truck transportation based on nature’s own highly effective solar energy capture system – plants. There is already significant biofuel industry tapping into that resource. The markets for Renewable Diesel and Sustainable Aviation Biofuel already draw a significant portion of soybean oil production, and ethanol production draws a significant portion of the corn crop. That does not necessarily translate into a problematic “food vs fuel” trade off because those biofuel industries also generate co-products for food and animal feed. Also, agriculturally sourced biofuels have been around for a long time. Consider the historical role of oats in the US – that was one of the crops that fueled animal powered transportation until the rise of the internal combustion engine (see graph below). Notice how oat acreage declined rapidly mid-last century while soybean acreage expanded. Corn acreage also increased, but it saw even faster gains in terms of per acre productivity.

As described in an earlier article, one way that plant-captured energy can increase fuel production without competing with food is to grow a “double” or “relay” crop on the same land as food crop but during a different time of the year. An oilseed crop known as Camelina is being optimized to pair with wheat and other common crops in Canada and the Northern tier of the US so both food and fuel are coming off the same acre in a given year. That practice also fits into the soil health and carbon capture strategy of keeping something growing on every acre for as much of the year as possible. Yield-10 Bioscience is an agricultural bioscience company that has pioneered Camelina development. They have developed regionally adapted cultivars with the herbicide tolerance traits that farmers desire in order to maintain their soil-health enhancing no-till and strip-till farming practices.

Yield-10 recently signed a Memorandum of Understanding with the global company Mitsubishi and the two companies are discussing a partnership. Mitsubishi is a major player in supplying fuel for aviation and heat pumps. They are focused on carbon footprint reduction, so the potential expansion of a plant oil supply beyond soybeans is something that they find very attractive. Yield-10 projects the potential to grow 100 million acres of Camelina and other new double crop options such as Pennycress and Caramanda.

On the long-haul trucking front, a company called ClearFlame Engine Technologies has raised $30 million in Series B funding by Mercuria, Breakthrough Energy Ventures, WIND Ventures and Rio Tinto, one of the world’s largest mining companies. Their engine technology allows existing diesel engines to run on a range of renewable fuels like ethanol. One of their target markets is companies with trucking fleets who would be able to arrange for refueling networks across the geography they serve. That would include large nationwide entities and mid-size fleets – particularly in the Midwest where ethanol is most readily available. There is also interest from the power generation, agriculture and mining sectors.

Again, this does not have to be a food vs fuel problem because corn is used to generate protein for feed and corn oil for food while at the same time supplying starch for an ethanol plant. In addition, the Distillers Dry Grain or “DDG” that is left over after the ethanol fermentation is a sought-after source of protein in cattle feed. Corn is a remarkably efficient crop for capturing solar energy. It does require a substantial amount of nitrogen fertilizer, but between new nitrogen fixing bacterial inoculants (e.g. products from Pivot Bio and Azotic) and the ascent of green ammonia production from wind and solar, the sustainability of this system is being improved. Not surprisingly many of ClearFlame’s investors are corn industry players, but there are also other strategic investors.

ClearFlame has successfully completed their initial alpha pilot demonstration with the next round of pilots scheduled with some of the largest fleets in the country. Fleets need very strong assurance that the modified trucks have the performance and reliability they need for their hauling business as well as a financial advantage in terms of fuel cost as well as TCO – total cost of ownership. Based on a recent analysis of the latter it appears that these players can, “make green by going green.” At today’s fuel prices, ClearFlame modified trucks would have a $0.29 per mile lower TCO than diesel trucks and, when using ethanol from cellulosic sources like corn stover or corn fiber, they could achieve a 69-83% reduction in GHG emissions. With their new funding, ClearFlame will begin scaling up modified trucks for additional customer pilots, continued R&D, and the remaining steps for regulatory compliance. They expect to begin generating revenue this year and project profitability within 2-3 years as they either retrofit their technology to existing diesel engines or develop license agreements with engine manufacturers.

So there is continuing progress with these plant-based strategies for transportation decarbonization.