Wood pellets are made either from the by-products of other wood manufacturing processes or from whole round wood.  The wood is dried, pulverized, and then forced under high pressure through the holes in a die, much like spaghetti is made.  Pellets can be made from either hardwood or softwood; premium or super premium pellets are very dry and have very little ash content. Softwood pellets often contain more heat per pound than hardwood pellets because of the resin in the wood.  Burning pellets does not create chimney deposits as burning cordwood can; in fact, there is no smoke visible from the chimney when pellets are burning. 

Pellets for bulk delivery are stored in large silos where delivery trucks load them for distribution to homes and businesses.

Pellets are taken from silos and delivered to home storage units which can be bins or silos indoors or outdoors.  These storage units can be of varying sizes, so that many residences can require only a couple of deliveries a year.  A home that burns 1,000 gallons of #2 heating oil would burn approximately 7.5 tons of premium pellets.  4 tons of pellets can be stored in a 6' cube in the basement.  Pellets must be kept dry so the storage containers are airtight.

Wood pellets are  delivered automatically by auger from the pellet storage bin to the burner on the boiler. The auger  is controlled by the burner; as it needs pellets it turns the auger on;  when the burner's small storage tank is full, it turns the auger off.

A pellet fired boiler works just as any other boiler does providing hot water to your baseboard radiation, radiators or radiant floor heating system and providing domestic hot water for your kitchen and bathrooms. Unlike oil boilers, pellet-fired boilers do require ash removal.  The six-section (~70,000 BTU) Bosch boiler will require ash removal two or three times a year.  The ash bin is light, and the ash is actually good for your garden or lawn, so disposal is a simple matter.

The Bosch pellet-fired boiler system distributed by Maine Energy Systems LLC does all this work while burning a carbon neutral fuel costing less than half as much as the identical quantity of heat derived from the #2 heating oil commonly used for residential heating in the Northeast.