© 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