Greenhouse gas emissions due to transportation make up nearly 29% of all greenhouse gas emissions in the United States.  The website Ars Technica discusses the possibility of powering large vehicles like trains, with batteries rather than diesel, to help reduce carbon footprint. With this rapid pace of technology change in smaller vehicles, it brings up the question of whether or not big modes of transportation, such as trains, planes, and ships, are able to join the wave of going green. A new study performed by California Based Researchers studies the possibility of electrifying rail-based freight. Technology is advanced enough to be able to make a plan like this work, but there is also an economic side that needs to be brought into consideration. 

Locomotives that run on diesel produce about 35 million tonnes of carbon dioxide per year. After discussing the different options, batteries seemed to be the most viable choice to quickly reduce carbon emissions from freight shipping. Using batteries to power locomotives was something that was looked at a few years ago, but was not feasible electronically or economically. Now, years later, researchers are re-evaluating this option. Within the United States, the average freight car travels 149 miles per day. Researchers created a large enough battery to move that amount of distance as part of a large freight. Although most large locomotives are powered by diesel, they are actually a type of hybrid. The diesel engines are just generators that produce electricity for the electric motors that actually move the train's wheels. Rewiring to reduce the need for the diesel generators could lower emissions without having to do a really major resdesign of how the trains actually work. 

Since freight vehicles travel so far each day, scientists were able to create a battery big enough to support this distance. Scientists found that lithium ferrous batteries would allow a large freight train to be powered by a single freight car run by a single battery. The direct electric power from the battery would make it so the train would only use half the energy that it would consume normally. Although scientists are able to confirm the stability of powering locomotives with larger batteries, the economic side will have to come into play, which will create some road blocks. Researchers estimated that switching to batteries would cost an estimated 15 billion dollars. Unfortunately, this estimate will increase as climate change continues to stay persistent. Check out the full Ars Technica article for more details.