PDCs are a new biomass fuel now available in New England, manufactured in Peterborough, NH at a plant operated by Froling Energy.
PDCs are PRECISION DRY Wood Chips:
PRECISION: Because we take in standard random sized green, mostly hardwood chips and put them through a screening process that filters out chips that are too large and re-chips them. Our goal is to have chips about the size of a standard match book–fairly regular in size and shape so they can be transported easily using augers and blowers.
DRY: The green wood chips that we make PDCs out of arrive with moisture contents of between 35% and 55%. Once they go through our processing, they have an assured moisture content of 25%.
WHY PDCs? Dry chips burn better and cleaner than green chips and they cost 35% less than wood pellets.
Download our Froling Energy PDC Brochure & Specifications
Most larger, high efficiency pellet boilers can also burn PDCs–with a few system design changes and modifications. Those modifications can usually be paid for very quickly with the fuel cost savings. PDC and Pellet systems usually are sized to cover between 90% and 95% of the average annual fuel usage (with oil or propane providing the balance as a peaking or back up heat source).
One of the key advantages of PDCs is that they are delivered into an interior storage bin by blowing them through a 5″ diameter pipe. Green chips come in via semi-trailer and require large buildings with pits and docks with big garage doors.
PDCs are not as energy dense as wood pellets–in fact they take up twice the volume of storage space for the same BTU value– but the savings usually make any additional investments very worthwhile.
How do PDCs compare to green or raw wood chips? Green chips have moisture contents between 35% and 55% while PDCs are at 25% which requires that your boiler burn as much as 55% more tons of fuel to be able to generate the same amount of heat for your building. Yes, they can cost a lot less, but the infrastructure required to handle green chips is also very different–and much more costly.
DOWNLOAD THIS CHART that shows some general costs of boiler systems and future fuel costs for each of the 3 types of biomass fuels, all for a hypothetical school using 50,000 gallons of fuel oil. Future Cost Predictor–Project + Fuel 50kGalOil CHART
While wood pellets can be stored a long way from the pellet boiler, PDC storage bins must be fairly close to the boilers they feed. This lack of flexibility makes a retrofit somewhat more difficult. However, most of our customers are burning PDCs to heat existing buildings.