Are Biofuels Carbon Neutral?
"Carbon neutral" refers to the balance between CO2 (carbon dioxide) released into the atmosphere and the amount that is removed of offset. When biofuels are produced from feedstocks - corn, sugarcane, soybeans, and so on - the CO2 released during their combustion is roughly the same amount as the plants absorb during their growth. This is the carbon cycle. The carbon emitted during combustion is offset by carbon absorbed during growth. In this case, these biofuels are considered carbon neutral.
However, not all biofuels are as carbon neutral as others. Certain factors, such as land-use changes, deforestation, or the use of fossil fuels during production, can disrupt the even trade of the carbon cycle. If the biofuels require the clearing of forests, for example, the change far outweighs the benefits of the biofuels. It also reduces the particular biofuel's carbon neutrality.
To ensure the carbon neutrality of biofuels, sustainable practices should be implemented throughout their entire lifecycle, from feedstock production to processing and distribution. This includes using feedstocks that have a low impact on land use.
With the expansion of the biofuels industry, you might be wondering how you can use biofuels in your own business. Below, we’ll discuss ways that companies can make the most of biofuels as part of their carbon management strategy to achieve carbon neutral transportation.
Common Uses of Biofuels
Vehicle Applications
Biofuels’ traditional application is in vehicles, such as ethanol blends with gasoline (E10, E15, E85). The Renewable Fuel Association has published data detailing today’s corn ethanol reduces GHG by half when compared to traditional fuels. In addition, ethanol has been the cornerstone of helping California meet approximately 40% reduction of GHG emissions for their new low carbon fuel standard. Increasing the blend levels of ethanol in gasoline will help States reach current low carbon fuel standards as vehicle fleets are electrified.
As vehicles electrify, the need for biofuels in passenger vehicles reduces. Electric vehicles being charged on a relatively clean grid may incur less GHG emissions than vehicles that run on 100% biofuels.
However, there is still a need for an adequate low-to-zero carbon option for certain types of transportation where electrification with batteries is not currently feasible (trucking, maritime, rail, aviation). The electrification of vehicles will take time and the use of renewable fuels will play a major role in meeting carbon reduction goals. Biofuels will compete as a solution with other technologies including Hydrogen and rail electrification (non-battery).
Aviation Applications
Since vehicle electrification has developed, the biofuels industry has begun pivoting to aviation. Like long-haul trucking, it is another transportation industry that cannot rely on batteries to decarbonize.
Biofuels would allow for aviation transportation to drastically reduce emissions. It will also allow aviation to potentially be carbon neutral, reducing their carbon footprint, depending on the type of biofuel, its feedstock, and the emissions associated with its production.
Long-Haul Trucking Applications
Electrification of long-haul vehicles with batteries is currently not feasible due to the weight of the batteries required. Renewable fuels such as biodiesel and ethanol offer a lower carbon option for the trucking sector.
Agriculture / Industrial Applications
The agriculture industry is unique because not only can it use biofuels, but it also contributes to their production. Like long-haul trucking, many of the vehicles and machinery in the agriculture industry aren’t being electrified (e.g., diesel tractors). Renewable fuels (ethanol, biodiesel, renewable diesel) could be the solution for decarbonizing scope 1 emissions incurred by operating farm equipment. Additionally, biofuel production requires crops such as corn, sorghum, soy, etc. This presents an opportunity for farmers to grow products in responsible ways (using sustainable farming techniques) that will ultimately be sold as biofuel renewable fuel feedstock.
Just this year in August, the USDA began accepting applications for $100 million in grants to increase the sale and use of biofuels derived from US agricultural products. U.S. Department of Agriculture (USDA) Secretary Tom Vilsack stated, “Biofuels are homegrown fuels. Expanding the availability of higher-blend fuels is a win for American farmers, the rural economy, and hardworking Americans who pay the price here at home when we depend on volatile fuel sources overseas.”
However, this is also where the “food vs fuel” conflict comes into play, where some have identified a risk that using suitable land for agriculture and/or food products as fuel feedstocks can create more price and land area competition.
It’s hard to find a consensus on the conflict in terms of risk quantification. Many renewable fuel producers use feedstock non-suitable for human consumption and produce co-products such as distillers’ grains for animal feed to replace the possible use of the original feedstock. In addition, it’s important to keep in mind that renewable fuels and electricity will not totally eliminate the use of fossil fuels. The decarbonizing goals of the future will be achieved by using a balance of fossil fuels like renewable fuels and electricity.
So, What Does Implementation Look Like?
It is important to account for biofuels correctly and anticipate how they will impact your greenhouse gas emissions accounting.
The environmental benefit of these fuels is seen in the upstream production of these fuels. Instead of extracting oil and gas, the plants used as feedstock uptake carbon dioxide, incurring a negative carbon emissions figure during their growth cycle that either partially or fully offsets the emissions generated in their production and ultimate combustion as fuel. Recent studies have shown that ethanol combustion produces significantly less GHG emissions than standard gasoline.
To take credit for the carbon uptake/offset associated with the biofuel, you need to have the Renewable Identification Number (RIN) credit. This certifies that only one entity is taking credit for the environmental benefit, and the benefit isn’t being double counted.
Accounting for the use of biofuels in your GHG inventory is nuanced. The Greenhouse Gas Protocol (and other reporting mechanisms, such as CDP Climate Change) allows for part of the scope 1 emissions associated with the combustion of biogenic sources (i.e., biofuels and other alternative fuels) to be reported separately from other scope 1 emissions. Specifically, the CO2 emissions are reported in a different category (e.g., “excluded emissions” or “biogenic emissions”), while CH4 and N2O are included in scope 1 as usual. This is to recognize that at least a portion of the carbon dioxide released from the combustion of the fuel was likely taken up by the feedstock earlier in its lifecycle.
The Bottom Line
Biofuels are certainly one piece of the complex decarbonization puzzle, especially for aspects of transportation industries that are not addressed by electrification via battery technology. Remember, the decarbonization puzzle will be achieved by using multiple forms of energy including fossil fuels, renewable fuels, and electricity. When it comes to reducing emissions, every step counts.
