Our Commitment to Renewable Energy On and Off the Farm
We have had a commitment to using renewable energy on our farm wherever practical since before we actually began farming. We knew as far back as 1997 when we built our first greenhouse, that petroleum was not going to be a sustainable way to heat greenhouses in Maine. We have been researching specific renewable fuel technologies that might have potential for us since then.
Biodiesel Off the FarmAlthough making biodiesel is not a practical solution for our farm we remain strong supporters of biodiesel manufactured to strict quality standards (ASTM D6751) for any application using diesel engines. Because biodiesel is not well suited for engine use in long term storage and cold climate applications of a farm in Maine, and because much of the biodiesel made in Maine ignores quality standards, we are not impressed with much on-farm produced of biodiesel. Follow the Biodiesel link at left to read more about our commitment to and participation in the biodiesel industry.
Renewable Energy On Our Farm
The complexity and cost of making biodiesel that is safe to burn in diesel engines makes the technology extremely difficult (in my opinion impractical) for on farm manufacture. This led to considerations of other, more simple and safe ways to use triglycerides as fuel on the farm. An analysis of our energy use showed that less than 1% of all the fuel used on our farm is diesel fuel and about 90% is heating oil. Because of this, we settled on using raw used triglyceride (cooking oil and animal fat) as heating fuel and sticking with reliable, safe diesel (ASTM D975) in our tractors.
Our heating system makes use of used animal fats and vegetable oils from local restaurants sometimes called Used Cooking Oil (UCO), now referred to as Triglyceride Burner Fuel (TBF). Some refer to these fats and oils as Waste Vegetable Oil (WVO). We reject this concept since these materials are truly a resource and not a waste. Unlike homemade biodiesel, our system uses no hazardous materials to make the oil burnable, requires no hazardous and complicated chemical conversion, and generates no hazardous waste. The only waste products are the food bits and watery waste cleaned from the TBF and the stack emissions which are considerably less than emissions of No 2 fuel oil.
At the present time, we operate three burners for a total of more than 3,500 hours per year. The burners each consume 2.5 gallons of TBF per hour, which means that we use almost 10,000 gallons of TBF each year resulting in savings of about $25,000 per year. The disposal savings to the restaurants in Freeport is estimated at about $8,000 per year. We are convinced that this concept is practical and can result in significant cost savings for greenhouse operators while providing a more environmentally friendly energy source. This is a win/win/win solution for everyone involved.