Spooner farmer uses horse ‘poo-bricks’ for heat
Sherry Sutton-Zanardo held a fuel brick she made from horse droppings. She and her husband, Matt, have been burning the “poo bricks” in their wood-burning furnace for the past two winters to help heat their home.
SPOONER — Sherry Sutton-Zanardo has discovered a new type of horsepower, making heating fuel from her horses’ manure.
She and her husband, Matt, burn horse manure collected from their three horses by making the manure into bricks. They have used the bricks to heat their rural Spooner home, Chickadee Hills Farm, for the past two winters and have found the bricks burn beautifully with no odor.
Sutton-Zanardo came across the idea to make the bricks while surfing the Internet for information about manure management. She learned one horse’s daily amount of manure, together with the bedding material, has 30 kWh of energy. This amount equals about three liters of fuel oil.
In recent years, greater attention has been given to the use of biomass material as an alternative fuel source. Along with bricks, companies have offered compressed horse manure in pellet or briquette form.
While the movement promoting the use of dried dung as a modern fuel alternative is relatively new, dried manure has been used since prehistoric times and is still being used in a number of countries throughout the world for heating and cooking.
Through her research, Sutton-Zanardo saw a number of models for “poo brick” devices. She then developed a design for a press and commissioned her farrier to build one for her at a cost of around $20 for materials.
Through trial and error, Sutton-Zanardo found using manure with minimal bedding works best for forming the bricks.
“I have practiced with many different combinations of manure and straw, manure and shavings and so forth, but the best is just straight horse manure,” Sutton-Zanardo said. “If you are cleaning out a stall with shavings, it is OK if there is some shavings on the manure, but too much will cause it to break apart wherever there is a large concentration of shavings.”
Sutton-Zanardo said she also had to experiment to find a method that made a nice finished product.
“It is necessary to add water to the manure, but not too much,” she said. “If you simply put the manure into the press as ‘apples,’ after it dries it delaminates as ‘apples.’ So it needs to be broken down into a mixture.”
The mixture is pressed to remove most of the liquid and the new brick is removed through a drop-down door at the bottom of the press and stacked to dry. The byproduct liquid is used in a “manure tea” to fertilize her garden.
“After pressing, you have to allow the bricks to dry for weeks,” Sutton-Zanardo said. “I don’t do it when it is cold, and it certainly wouldn’t work if it were below 32 degrees.”
Her bricks are kept under an overhang located on the south side of their barn. Dry manure is typically defined as having a moisture content of less than 30 percent. Because of the lack of moisture, the bricks are nearly weightless, especially compared to firewood.
“They store well, but do not stack them where they can get damp,” she said. “I stacked some in the barn alleyway, which is concrete, and next thing you know I was growing mushrooms.”
Although Sutton-Zanardo believes they could make enough manure to heat their house for the entire winter they have only used manure for about one-third of their total heat source.
“That is just because I get tired of making poo bricks, which is silly because in the winter they are a lot easier to tote around than wood,” she said.
Anyone interested in learning more about using horse manure as an alternative fuel source can contact Sutton-Zanardo by emailing email@example.com or by calling 715-816-4103.