Why We Started The Grant Project

Since 1997 Ralph has been researching what energy options may be available to a small greenhouse producer like Laughing Stock Farm on the southern coast of Maine for heating greenhouses using local biomass. The best solution currently available is the direct burning of animal fats and vegetable oils (Triglyceride Burner Fuels - TBF) collected from local restaurants. TBF can easily be burned in commercially available waste oil burners. The kind of burner used to burn used automotive lubricants.

The most logical option up to now has been wood. We live in a densely populated area of the state and cannot afford a woodlot. Also, wood is a fairly dirty and labor intensive fuel. We do not believe that the state's problems could be solved if everyone burned wood because of the high particulate and other emissions from wood furnaces and boilers. It's true that wood is a renewable non-fossil carbon fuel, but as anyone who has had a wood stove knows, it makes lots of smoke. Still, though it will not work for us in Freeport, wood remains a good viable solution for areas of the State where no better options exist.

Another option is Biodiesel which is typically made from surplus soy oil, but can also be made from used cooking oil (UCO). We have strong supplies of UCO in Freeport relative to our energy use. We decided not to make biodiesel because: Extremely hazardous materials are used to make biodiesel, the process is not as simple as some would have you believe, and the glycerol byproduct must be disposed of as EPA listed hazardous waste because it is too contaminated with impurities to have any economic value. To make 100 gallons of biodiesel, you need to use 20 gallons of methanol, which is a hazardous material, and you loose 20 gallons of the batch mixture as wastes and glycerol byproduct. Finally, it takes about 500 gallons of fresh water to wash impurities from a 100 gallon batch of biodiesel. That water then must be disposed of properly. That's a lot of waste and a lot of hazardous material. There must be an easier way...

Direct burning of the TBF became an option when I found two companies who make commercial sized waste oil burners for automotive waste oils and who claimed that their burners would burn vegetable oil. Industrial users of vegetable oil, like McCain's in Aroostook County, have burned their UCO in industrial boilers for years. Many commercial waste oil burners will not burn TBF because of the glycerin content of the TBF, which is the same reason it cannot be burned in compression ignition (diesel) engines. It clogs and cokes the internal components in a very short time. It also has a flash point of about 380 deg F, making it extremely difficult to burn completely. Most waste oil burners use compressed air to assist in atomizing the waste oil for better combustion, and a small heater block to make sure the waste oil stays liquid during the flow and atomization. The hot water boiler we are now using includes a ceramic inner chamber and target to radiate heat back at the flame contributing to complete combustion. The hot air furnaces we are using do not use the ceramic chamber and we still get complete combustion.

After one disastrous year using a burner made by INOV8 that did NOT work, we changed to a system made by the Clean Burn of Leola, PA. We now use the Clean Burn burners exclusively, three of them, because they work really well and are easy to maintain.

The best estimates are that about 1,500,000 gallons of UCO are hauled off every year from restaurants in Maine. It is not clear to me why some in Maine are so strongly advocating that we ship in 300,000 gallons of hazardous methanol from outside the state when the purpose of the methanol is to throw away 250,000 gallons of glycerin, a perfectly usable heating fuel. That amount of UCO contains about 3.3 trillion BTUs. Not as big a number as the national debt, but clearly making biodiesel from Maine's UCO is not the most energy efficient way to use the limited UCO resource we have in Maine.

That said, I remain convinced that making biodiesel from surplus soy on a national scale under strict quality standards is a very good thing and I strongly support biodiesel that is produced commercially to ASTM D6751 quality standards.

Follow the links at left and below for a tour of our system.

Collection - This section shows how we get the oil we use. This part of the process requires a driver to pick up full 55 gallon drums and leave empty drums in their place.

Oil Processing - This section shows how we clean the oil to burn it for fuel. This part of the process requires an worker to move drums, turn valves, clean strainer screens, and operate the pump.

Oil Use - This section describes the burners and shows how the oil is burned. This part of the process is fully automatic.

UL Certification - We are continuing to work with Clean Burn toward a TBF burning specification that will allow Underwriter's Laboratories to list and label these systems as safe and reliable. At present we are very close to having an approved Standard Specification for TBF, which is being developed within ASTM.

Economics - The bottom line. Although it seems obvious that relatively free TBF is a better deal than $3.00/gallon petroleum oil, there are drawbacks to and costs to TBF use. TBF use is not for everybody, but for growers who are already managing wood, or other alternative energy systems, this may be a good alternative provided there is a stable supply of TBF in their area. Freeport is a perfect location for this project. We can already say that without this project, we would not have been able to operate our greenhouse during the winter. We are continuing to expand this system to heat additional greenhouse space as time and capital allow.