1. Michigan Air Quality Division
Greenhouse Gas BACT Analysis for
Wolverine Power Supply Cooperative Inc.
G. Vinson Hellwig, Chief
Air Quality Division
Michigan Department of Environmental Quality

2. Project consists of two 300MW (net) circulating fluidized bed (CFB) coal-fired boilers and auxiliary equipment Project site is located in Rogers City, Michigan, and would provide base load power in northern lower Michigan

3. BACT analysis for conventional criteria pollutants completed prior to submittal of GHG BACT analysis GHG BACT analysis submitted in March 2011 as a supplement to original BACT analysis

4. Step 1 - Identify control options
Technologies Considered: • Carbon Capture and Sequestration (CCS) • Combined Cycle Gas Turbine (CCGT) • Pulverized Coal (sub-critical, supercritical, ultrasupercritical) • Circulating Fluidized Bed (supercritical) • Integrated Coal Gasification Combined Cycle (IGCC) • Biomass Gasification • 100% Biomass Combustion • Energy Efficiency • Combined Heat and Power (CHP)

5. Step 2 – Eliminate technically Infeasible Options
Not feasible: • Combined Cycle Gas Turbine (CCGT) • Pulverized Coal (sub-critical, supercritical, ultrasupercritical) • Integrated Coal Gasification Combined Cycle (IGCC) • Biomass Gasification • 100% Biomass Combustion • Combined Heat and Power (CHP)
CCGT – redefinition of source; lack of NG supply; limited fuel flexibility (couldn’t burn biomass); doesn’t take advantage of site specific options (limestone availability for SOx control, on-site cooling water port for solid fuel delivery, landfill for ash); high fluctuation of fuel costs; less attractive option overall
PC – fuel input limitations therefore infeasible; doesn’t take advantage of site specific attributes; also could be eliminated in Step 3 due to lower ranking than CFB
IGCC – determined to be cost prohibitive for criteria pollutant control; fuel input limitations therefore infeasible; no advantage in GHG emissions over other designs
Biomass Gasification & 100% Biomass Combustion – limitations on biomass feedstock supply; not demonstrated at size proposed by WCEV
CHP – eliminated in previous analysis because no options for nearby users of steam
Most of the these technologies were eliminated is because they redefined the source, were considered to be in developmental state, or in the earlier analysis for criteria pollutants.

6. Step 3 – Rank Remaining Technologies
Remaining Technologies: • Circulating Fluidized Bed (supercritical) • Carbon Capture and Sequestration (CCS) • Energy Efficiency • Biomass Fuel Augmentation

7. Supercritical Circulating Fluidized Bed Boiler
Eliminated from further consideration because: • Only one supercritical CFB known to exist in world (built in 2009 in Poland) • Known supercritical CFB burns only eastern european bituminous coals • Very limited data

8. Carbon Capture and Sequestration
Carbon Capture technologies reviewed:
• Absorption • Adsorption • Physical Separation • Hybrid technologies • Biological uptake (algae farms) • Oxy-firing
Absorption – typically amines, lime and other proprietary materials being investigated
Adsortpion – zeolite, activated carbon
Physical – mambrane technologies, cryogenic technologies
Hybrid – combinations of chemical absorbents/adsorbents & physical separation
Biological – algae farms with bio-engineered algae strains
Oxy-firing – not really a capture technology but can be used to concentrate dilute CO2 streams

9. Carbon Capture and Sequestration
Carbon Sequestration technologies reviewed:
• Terrestrial - Offsets • Geological - Sequestration • Compression & Re-use

10. Carbon Capture and Sequestration
CCS eliminated based on: • cost • increase in plant size to accomodate parasitic load required to operate CCS equipment
Cost effectiveness was about $126/ton based on a slipstream of 5%
Total add’l cost for 5% slipstream is on the order of 30% of base cost of plant
Would require an increase in plant generating capacity of at least 20%

11. Biomass Fuel Augmentation
Michigan PA 295 requires electric service providers to establish renewable energy programs 75-mile radius around site could theoretically support up to 20% biomass Feedstocks over 5% biomass can negatively affect boiler efficiencies at high moisture contents
5% biomass selected as BACT

12. Energy Efficiency
Variable speed motors over 100 hp Thermal efficiencies Minimize pressure drops across control equipment
Permit includes requirement for design specs, Energy Efficiency Plan (EEP), and output based limits
Energy Efficiency selected as BACT

13. Questions?