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A Utility Perspective on Renewables and Biomass
Doug Boylan – Southern Company
Traditional Utility
•Goals– Low cost, reliable energy provider
•Selected technologies– Hydro, nuclear, coal, natural gas
Drivers Toward Renewables
• Green house gas mitigation• Market demand for Green
Power• Government mandated
Renewable Portfolio Standards (RPS)
• Seeking lowest cost renewable energy options
Seeking Low Cost Large Scale Options for RPS
(Southeast US)• Solar - $$$• Wind – Good, but limited in resource• Landfill gas – Good, but limited resource• Small hydro – Good, but limited resource• Biomass – Good? • Purchase Credits – Sets renewable cost
cap
Biomass OptionsCo-firing
•Uses existing plant•Displaces coal directly•Reduced capital costs•Application limited by ash and
operational considerations•Co-Mill – limited percentage (3-
5%)•Direct Injection – Higher
percentage (10 - 20%), higher cost
Biomass OptionsGasification
• Higher capital cost• Higher efficiency• Displaces a higher
cost fuel• Greater potential
to meet large RPS generation needs
Grass Wood
Fuel Cost ($/MMBtu) 3 – 4 2 – 3.5
Moisture 10-15% 20-60%
Metals Low Low
Sulfur Low Low
NOx Moderate N Low N
Slagging and Fouling High K Moderate K
Catalyst effect High?Moderate?
Ash sales ? Non-spec Low Non-spec
Co-fire ¢/kWh (Est.) 2.6 – 3.0 0 – 2.6
Gasification ¢/kWh (Est.) ? 1.0 – 3.0
Grass Wood
Fuel Cost ($/MMBtu) 3 – 4 2 – 3.5
Moisture 10-15% 20-60%
Metals Low Low
Sulfur Low Low
NOx Moderate N Low N
Slagging and Fouling High K Moderate K
Catalyst effect High?Moderate?
Ash sales ? Non-spec Low Non-spec
Co-fire ¢/kWh (Est.) 2.6 – 3.0 0 – 2.6
Gasification ¢/kWh (Est.) ? 1.0 – 3.0
Contrast Wood and Grass as Fuels
Biomass - Closed and Open Loop
• Biomass will probably need tax or other incentives to compete
• Tax incentives have tended to favor Closed Loop
• Grass probably has the best opportunity to be Closed Loop
ConclusionsFrom the Utility perspective:
•Biomass has potential to supply RPS requirements
•Grasses and wood each have advantages and disadvantages
•Utility desire is to keep funds in our service area
•Biomass will probably need tax credits or other support to be viable for renewable energy
Questions?
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grass benefits co-mill benefits dir inj benefits
Co
st
Dif
fere
nti
al
($/k
wh
)Sulfur benefit
NOx benefit
milling energy cost
Labor cost
Capital cost
fuel diff cost
Costs of Co-Fire