Advanced Biomass-based Combined Heat and Power System Combined Heat & Power in the Pacific Northwest October 15, 2002 Nathan E. Carpenter Manager, Energy Boise

Presentation Outline Forest Industry Energy Overview Typical Forest Industry CHP Application Proposed Next Generation Systems Technology Gaps Policy Issues Summary

Forest Industry Energy Overview Ranked third in overall energy intensity Main users are the integrated pulp & paper facilities Industry 54% self-sufficient, mainly due to biomass ~65% of thermal needs generated internally ~25% of electrical needs generated internally

Typical Forest Industry CHP System Ash & Char Steam Turbine Natural Gas BFW Steam to Mill Air Stoker Boiler Bark & Solids To Flue Gas Cleanup Conventional stoker fired combination fuel boiler High pressure topping cycle using back-pressure steam turbine-generator with low pressure exhaust to process heat loads Natural gas used strategically to increase reliability and stabilize combustion Fuel to electricity efficiency 62-73%(cogeneration mode with some natural gas firing) Capital $1500 to $2000 / kw

“Traditional” IGCC Approach to Biomass-based Power Generation High pressure (15-25 ATM) biomass feeders, gasifier, ash and fines removal, and hot gas cleanup system Low caloric value gas turbine topping cycle and steam turbine bottoming cycle Fuel to electricity efficiency % Capital $1500 to $2500 / kW NO x emissions over 150 ppm High Pressure Combustor Heat Recovery Steam Generator High Pressure Gasifier High Pressure Hot Gas Cleanup Clean Fuel Gas Air to Gasifier Bark & Sludge Air Ash Hot fuel gas Gas Turbine Steam Turbine Condenser Air Water Steam Flue gas High Pressure Feed System Fly Ash High Pressure Fly Ash Removal High Pressure Ash Removal

“Evolutionary” Approach to Biomass-based Power Generation H 2 -rich syngas increases wood waste utilization and boiler capacity Low pressure biomass feeders, gasifier, and ash systems System uses existing flue gas cleanup system Gas turbine topping cycle only- using HP heated air as working fluid Natural gas used strategically to increase reliability and increase power generation efficiency Fuel to electricity efficiency 65-73% (cogeneration mode) Capital $1000 to $1500 / kW NO x emissions below 60 ppm Gasifier Ash & Char Ash Syngas Gas Turbine High Pressure Combustor Natural Gas BFW Steam to Mill Air Existing Stoker Natural Gas (Backup) Bark & Solids To Existing Flue Gas Cleanup 1800 F 2200 F (Backup )

Benefits and Features of Advanced Biomass-based Power Generation l Utilizes existing infrastructure l Increased biomass usage for electricity generation l Increased biomass usage for steam generation l Improves boiler performance – Improved load following – Increased efficiency – Higher carbon burnout Increased steam capacity l Reduced electricity costs Reduced emission Gasifier Ash & Char Ash Syngas Gas Turbine High Pressure Combustor Natural Gas BFW Steam to Mill Air Existing Stoker Natural Gas (Backup) Bark & Solids To Existing Flue Gas Cleanup 1800 F 2200 F (Backup )

Technology Gaps Materials for HPHT Air Heater Gas Turbine System for HPHT Air Utilization of Hot Air Generation System Integration Gasifier Ash & Char Ash Syngas Gas Turbine High Pressure Combustor Natural Gas BFW Steam to Mill Air Existing Stoker Natural Gas (Backup) Bark & Solids To Existing Flue Gas Cleanup 1800 F 2200 F (Backup )

Policy Issues Permitting hurdles Recognition of societal benefits Technical support Financial incentives

Summary Forest products facilities are excellent host sites for distributed, combined heat and power projects Renewable energy based Additional societal benefits Regional synergies Need financial incentives and technical support