In 1993 Sanborn Industries, an Iowa based wood waste pallet hauling Company, approached Charlie Cary to determine if he knew of any wood waste boilers needing wood fuel. Charlie responded that all his boiler customers produced their own fuel, but many industries outside the forest products industry could use Sanborn’s woody material as fuel. With Charlie’s help Sanborn was able to find a market for its wood residue at Simonsen Rendering in Quimby, IA. Simonsen has now been burning wood fuel in a Horizontal Zoned Grate based wood fired boiler which Charlie sold them for over ten years and Simonsen could not be happier.

“We would not be in business if it was not for that wood boiler” states Jeff Simonsen who runs the facility. “In my business you can not stop running when high winter energy prices cut into profits because people will take their business to the competition. With locally supplied wood fuel Simonsen Rendering has a competitive edge when fossil fuel prices increase”.

Since northwest Iowa based Simonsen Rendering does not produce wood residue, and is not near any large sawmills, it is not the first place one would expect to find a wood fired boiler. The original wood supply contract with Sanborn included substantial trucking costs in the purchase price of $3.30 a million BTU. The project had a 2.5 year payback because the cost of propane was $5.50 a million BTU and the Company received a small grant from the State of Iowa. In 2004 Simonsen is paying between $2.50 and $4.00 per million BTU for wood fuel as compared to $7.00 per million BTU for propane. “We started out with a supply contract with Sanborn” says Jeff, “but quickly determined we could always find wood for less money if we shopped around”.

“Maintenance costs vary with the fuel quality” claims Mr. Simonsen. “With good clean fuel we rake the ash once a day which takes about 15 minutes and clean the tubes every three weeks which takes about an hour and a half. We tried burning poultry litter since it is available for almost no cost, but determined the manpower requirements for keeping the grate clean did not pencil out even though the fuel burned OK”

The boiler is designed to receive 2.5” minus wood chips and sawdust. All wood is chipped to this specification before delivery although Simonsen’s system puts the fuel over a screen to ensure fuel quality. Wood is delivered from furniture plants and pallet recyclers in 40’semi trailers equipped with “walking floors” which automatically drop the fuel onto a warehouse floor. A couple of times a day the wood is picked up by a front end loader and dropped into a bin which automatically feeds the boiler on demand. The boiler will burn up to 2,600 lbs/hr of dry pallet waste.

“Making an investment in wood energy makes sense for the long run” states Jeff, “Not only does my bottom line stay healthy when the price of fossil fuel increases but I have piece of mind of knowing that I can shop locally for my energy needs” .