Heating/Piping/Air Conditioning Engineering, June 2014, by Dan Vastyan.
http://hpac.com/heating/wood-pellet-fired-boilers-provide-highly-efficient-no-fuss-operation

"The Pennsylvania Department of Conservation and Natural Resources (DCNR)...wanted a district hydronic heating system fired by a renewable fuel—ideally, wood for its Resource Management Center—in Weiser State Forest in eastern Pennsylvania.

After reviewing several proposals, the DCNR chose a solution offered by ATI Systems Inc., a hybrid representative/distributor/engineering-services organization based in Conestoga, Pa., whose founder, Carl Longenecker, has found a way to burn wood automatically at near-condensing efficiencies with an air-friendly emissions profile vastly beyond traditional wood and coal burners
."