Pellet/Chip Quality, Integrating Boilers into High-Temp Systems, and Maximizing Boiler Uptime Industry Forum March 30, 2016

Industry Forum Pellet/Chip Quality Integrating Boilers into High-Temperature Distribution Systems Maximizing Boiler Uptime

Precision Dry Wood Chips  Screened to be average size of 1.5” long x 1.5” wide x.25” thick.  Moisture content is assured to be 25%  Hardwood 90% and Softwood 10%  Ash content: Less than 2.5%  Volume: 4.9 cubic yards per Ton at 25% moisture (15 lbs per cubic foot)  High Heating Value (HHV) Energy Content: 6495 BTU/pound (12,990,000 BTU/ton)  Tramp metal, occasionally found in green chip deliveries, is removed in processing. Oversized chips, sticks and rocks are also removed.  Made from sustainably harvested trees  Made from bole wood (main stem of a tree)  Quality Assurance—All PDC chips go through screening, drying and quality control process before they are delivered. If our chips cause a problem in your equipment, we fix it.  Thermal Renewable Energy Credits: with 84% burn efficiency PDCs yield approx. 3.0 Megawatts per ton (3 T-RECs) (Mass & NH Only)

Industry Forum Pellet/Chip Quality Integrating Boilers into High-Temperature Distribution Systems Maximizing Boiler Uptime

Moneyball “It should be obvious that the purpose of an offense is not to compile a high batting average.” Michael Lewis, Moneyball, p. 76.

Moneyball “It should be obvious that the purpose of an offense is not to compile a high batting average.” a boiler plant efficiency rating Michael Lewis, Moneyball, p. 76.

pellet boiler "OFF" setpoint controller pellet boiler "OFF" sensor outdoor temperature sensor outdoor reset controlle r to / from load from boiler to boiler (S2) (S1) (S3) tekmar 256 $150 Johnson A419 $59 Honeywell L4006A2007 $74 Temperature stacking (using 1 setpoint temperature and one outdoor reset temperature) (R2 ) (R2-1) 24 VAC pellet fired boiler T T (R2- 2) contacts T target +5 ºF T target -5 ºF contacts: 165 ºF open at 175 ºF (S1) (S outdoor ) tekmar 256 reset controller pellet boiler enable tekmar 150 setpoint controller (S2)

Temperature cycling range of storage is high dependent on the type of heat emitters used outdoor temperature (ºF) 0-10 water temperature cycling range in thermal storage (ºF) mixing HIGH temperature heat emitters No outdoor reset control of supply water temperature LOW temperature heat emitters No outdoor reset control of supply water temperature outdoor temperature (ºF) 0-10 water temperature cycling range in thermal storage (ºF) pellet boiler start pellet boiler stop Low temperature heat emitters allows for wider tank “draw down.” pellet boiler stop pellet boiler start

A comparison of tank temperature cycling range mixing OR to/fro m heat source mixing with 3-way motorized valve outdoor temperature (ºF) 0-10 water temperature cycling range in thermal storage (ºF) High temperature heat emitters No outdoor reset control outdoor temperature (ºF) 0-10 pellet boiler stop pelle t boile r st rtrt High temperature heat emitters With outdoor reset control of pellet boiler start temperature pellet boiler stop pellet boiler start outdoor temperature (ºF) 0-10 pellet boiler stop pellet boiler sta rt Low temperature heat emitters With outdoor reset control of pellet boiler start temperature Mixing of supply water temperature required water temperature cycling range in thermal storage (ºF)

Boiler Plant Effectiveness (BPE) Each bar represents a boiler plant in the or heating season. Some plants have bars in both seasons. BPE = % of heating time when boiler plant is providing water ≥ setpoint − 2.5°C OR Output of all available boilers > 95% of full output (undersizing not penalized) BPE is a performance metric, not an efficiency measure

Storage Tank ΔT Results

Industry Forum Pellet/Chip Quality Integrating Boilers into High-Temperature Distribution Systems Maximizing Boiler Uptime

Moneyball “Baseball keeps copious records... Why doesn’t anybody use them? Why doesn’t anyone say in the face of this contention or that one, ‘Prove it’?” Michael Lewis, Moneyball, p. 75.

Boiler Faults and Shutoffs Lead to Large Performance Penalties Possible reasons for shutoffs and faults: Manufacturer—boilers not rugged and fault often Service provider—lack of timely repairs keeps boilers in fault Operator—fails to ensure steady fuel supply or to clear faults quickly ✔ BPE = % of heating time when boiler plant is providing water ≥ setpoint − 2.5°C OR Output of ALL boilers > 95% of full output Each bar represents a boiler plant in the or heating season. Some plants have bars in both seasons. Had all boilers been available when temperature goals not met, these performance penalties = 0% BPE

Many Boilers Can’t Heat 24 Hours a Day Average time in fault per day (hours) StartupShutdownHeating

Pellet/Chip Quality, Integrating Boilers into High-Temp Systems, and Maximizing Boiler Uptime Industry Forum March 30, 2016