© 2003 Reliant
Reliant Seward Station CFB: Successful
Conversion of Waste Coal into Energy
Energy from Biomass and Waste SymposiumSeptember 27, 2007
2© 2003 Reliant
Energy/Electric Power
Steam Electric » Coal» Other fossil
• Biomass• Shale
» Nuclear» Combined cycle
Simple Cycle» Combined cycle» Combustion turbine
Fuels Cells & Thermo Nuclear Renewables
» Wind» Solar» Hydro» Pumped storage» Other renewables
• Geothermal• Wave• etc
CoalWood, refuse, etc
NuclearPetroleum, distillates, PNG/LNG
Fuel
3© 2003 Reliant
Electric Power Projections (DOE)
Total Electricity Generation (Gwe)
2004 - 629.802005 - 648.182006 - 649.492007 - 664.692008 - 677.082009 - 693.452010 - 701.992011 - 711.072012 - 718.012013 - 723.45
Centralized vs. Distributed Systems•Valuable infrastructure
Generation by fuel type (2008)
Coal 82%
Petrolium .6%
Natural Gas 6%
Nuclear 9%
Renewables/other 1.1%
~ 2% growth/annum
2025 (Coal 75% Gas12%)
4© 2003 Reliant
Seward – Legacy of Coal Mining in Pennsylvania
• Waste Coal (“boney”)• Blights the landscape• Contributes to Acid Mine
Drainage (AMD)• As a fuel, waste coal is
Higher than some sources:• sulfur• ashYet Lower than most sources in
energy value• CFB technology can cleanly
convert waste coal into energy
5© 2003 Reliant
Seward - CFB
Aerial Photo – October 2006
• 521 net MW
• Fuel BTU
• 5500 BTU
• 51% Ash
• 2.75% Sulfur
• DOE Clean Coal Technology
• CFB – Circulating Fluidized Bed
6© 2003 Reliant
Seward – How
Pollution Control Technology
• SNCR – NOx
• Limestone/FDA – SO2
• Baghouse
• Fuel – Barn and Covered Conveyors
• ~ 3.5M tons per year refuse
Steam
Water
Ash CollectingBaghouse
Furnace
Cyclone
LimestoneFuel
Ash Air
Seward CFB Schematic
7© 2003 Reliant
Seward – Air Emissions
Permitted Emissions (lb/MMBtu)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
NOx SO2 PM
Old Plant CFB
• NOx – Down 74%
• CFB low temperatures
• Selective Non-Catalytic Reduction (SNCR)
• SO2 – Reduced 85%
• Limestone injection
• FDA – Flash Dry Absorber
• Particulate Matter – Down 90%
• Fabric filter (baghouse)
• Enclosed fuel storage
8© 2003 Reliant
Seward – Generating Capacity
• Generating capacity increases 2-1/2 times
• Energy production will increase even more
• New plant should run as “baseload” (~ 24/7)
Change in Generating Capacity (MW)
0
50
100
150
200
250
300
350
400
450
500
550
Former Repowering
9© 2003 Reliant
Seward – Future Challenges
• Hg• GHG• Holistic – multi-faceted approach to
energy• Manufacture• Consumption
