I am pleased to have the opportunity to interview Seth Fore, a masters student at the University of Minnesota Crookston who has been working with professor Paul Porter to study small-scale on-farm biofuel production.
Their project is an innovative approach to farm-based energy sustainability that has been supported with both CERTs staff time and seed grant funding.
We are also happy to share a presentation about this project at the end of this post.
Joel: You have recently completed your masters thesis studying cold presses and their potential utility for various crops in Minnesota. How did this project begin?
Seth: During 2006, amid rapidly escalating diesel fuel prices, we became aware of increasing regional interest in small-scale biofuel production using oilseed crops such as canola, sunflower, and soybean. Since the Upper Midwest is well suited to the production of these commodities, the small-scale on-farm biofuel production system appeared to be a potential way for certain producers to stabilize income by offsetting risk associated with increasing diesel prices. Case studies were conducted on several preexisting small-scale biofuel production operations in Northwest Wisconsin to get an idea of the real time opportunities and challenges associated with the system. Concurrently, a pilot project was coordinated in northwest Minnesota where farmers produced biodiesel from canola.
Joel: Tell us a little about this press and how it works.
Seth: The most suitable press for small-scale crushing is what is called a mechanical press. A rotating screw inside a horizontal cylinder with a capped end exerts a large amount of pressure on the oilseed expelling the oil out of small holes along the cylinder wall while the meal is forced out a hole at end of the cylinder. Mechanical presses vary extensively in capacity. Those commonly used for small-scale on-farm crushing, such as the Komet DD85G used in the northwestern Minnesota pilot project, range from 1,500 to 2,500 lb d -1. The oil extraction efficiency of mechanical presses typically ranges from 65-75% depending on the type of oilseed being crushed and the rate of throughput. Optimal press configuration is most appropriately dictated by the total demand for either oil or meal and the time frame of demand.
Joel: This press has toured around a little. Where has it been and what has been studied?
Seth: Besides being used in the northwest Minnesota pilot project, the press has been used for numerous farm and extension demonstrations in North Dakota, Minnesota, and Wisconsin. Objectives including the suitability of different midwestern oilseeds for mechanical crushing, oil extraction efficiency for different feedstocks, the impact of crushing speed, and heat application on oil extraction efficiency were studied with the press.
Joel: Where is the press now?
Seth: The University of Minnesota Crookston has played an ongoing role in our research on small-scale on-farm biofuel production systems. The press currently resides on the UMC campus where we are conducting further research looking at burning straight vegetable oil in modified diesel engines. Additionally, the press will likely become part of an emerging renewable energy curriculum taking shape on the UMC campus.
Joel: What kinds of grains have been put through the press, and what are some of the preliminary findings?
Seth: We have crushed canola, soybean, sunflower, hazelnut, and camelina. This is, however, not an inclusive list of potential oilseeds that could be crushed using this style of press. Oilseeds including jatropha, pennycress, and other exotic oilseed may also be good candidates. In our experience, the most easily crushed oilseeds were canola and sunflower. Soybean can be crushed with minimal effort after the press is correctly set up. Hazelnuts that have not been dehulled proved very difficult to crush. In total, many oilseeds can be crushed; however, some differ in the amount of time and effort required to set up and refine various crushing parameters.
Joel: What type of biofuels can be produced with the extracted oil?
Seth: Biodiesel can be produced from straight vegetable oil (SVO) via a chemical reaction called transesterification using alcohol (commonly methanol) and a base catalyst (commonly sodium hydroxide or potassium hydroxide). Biodiesel can be burned in unmodified diesel engines displacing diesel fuel. Alternatively, many researchers both in Europe and increasingly in the USA are looking at burning SVO in certain modified diesel engines. Using SVO is advantageous, as it requires far less processing than biodiesel resulting in reduction in cost per gallon. Both small-scale production and safe use of biodiesel and SVO biofuels are actively being researched at the University of Minnesota.
It ought be mentioned that neither biodiesel nor SVO produced on-farm can be legally sold to a third party. Biofuels produced on-farm must be used on-farm by the producer. Standards exist for biodiesel, however testing is expensive thus cost prohibitive for small-scale producers. No standards are currently in place for SVO. SVO use in diesel engines is still in the testing phases in the USA and requires a federal permit for legal use.
Joel: In recent presentations, it was striking that if a soybean farmer didn’t mind putting the system together, had some livestock to consume the soybean meal and an out building to heat with the soybean oil, even with conservative estimates this system really pencils out. Can you go into further detail about this?
Seth: There are indeed certain operations where the small-scale on-farm biofuel production system appears to provide substantial savings to producers. The amount that a producer can save by producing their own biofuel depends on type of biofuel being produced, e.g. biodiesel, SVO for diesel engines, or SVO for heating applications, and the market price of the product being displaced, e.g. diesel fuel or heating oil.
A recent study examining the economic viability of biodiesel and SVO from canola or soybean for use in diesel engines produced on-farm suggested that SVO was consistently more cost competitive than biodiesel due to reduced input costs. Furthermore, SVO and biodiesel produced from soybean were less costly than the same produced from canola. This was primarily due to the impact of the meal co-product credit, which was substantially larger for soybean than canola resulting from its greater nutritional value.
A particular application of promise is using SVO as a heating fuel. This application requires minimal SVO processing and is not subject to the potential problems and regulations of burning SVO in diesel engines.
Joel: What is next for you?
Seth: I am pursuing my PhD. at the University of North Dakota. I hope to continue working with renewable energy production. I am interesting in the associated of energy and food production, the impact of increasing biofuel production on ecosystems, and how small-scale energy production can be a part of an emerging diversified energy production portfolio.
Joel: How can people learn more?
Seth: You can check out the presentation that I’ve shared (below) or visit our website on the project.
Sustainable Biofuels in Minnesota: Opportunities of Small-Scale On-Farm Biofuel Production
