Co-firing/firing Biomass in Coal Fired Power Plants
Issue: Biomass co-firing or firing in Coal Fired Power Plants is seen as an alternative for decrease the Coal based Power Plant emission. Also, is considered around the world as an alternative for the energy independence and the substitute of non-renewable source by renewable sources of energy. Alberta presents special considerations.
· Between 1998 and 2005 were decommissioned five Power Plants in Alberta, the equivalent to 324 MW.
· Between 2010 and 2013 it will be decommissioned four Coal Power Plants in Alberta, the equivalent to 718 MW; these power plants represent the 6% of the power capacity in Alberta today and they have a GHG emission around 20% higher than the average GHG emission in Alberta.
· Alberta has coal for feeding Coal Fired Power Plants for around 900 years at the current rate of consumption. The coal is a cheap fuel for electricity production; this produces a strong constraint in the electricity market.
· Due to the huge energy reserves, the concern about energy independence is absolutely different in Alberta compared to most of jurisdictions.
· In Alberta, sub-bituminous coal is mostly used for electricity generation. The Coal power plants use boilers adapted to this kind of coal.
· Alberta’s forest industry is in a critical situation; the market value has fallen 36.2 % between 2004 and 2007.
· Alberta’s forest industry strongly helps with community development.
· Biomass term could involve more than 50 different products including wood derived, algae and crops.
· The conversion of coal fired power plants to co-firing biomass has more than 30 years of study in USA.
· 174 world wide Coal fired plants are in process, or finished, to be converted in co-firing biomass Power plants.
· Most of the experience in that conversion is with sub-critical pulverized coal Power Plants using bituminous and lignite coals.
· The coal power plants retrofit designed for sub-bituminous coal is cheaper; this is due to the most close characteristics between the sub-bituminous coal and biomass as fuel for power plants.
· Under The Integrated Power System Plan, Ontario plans to replace Coal Power Plants by 2014;
· Ontario and the Federal Government started the study of co-firing and complete conversion of Coal fired plant two years ago.
· In January 2009, in an attempt to extend the life of some power plants and under Wood Pellet Association of Canada proposal, Ontario announced the conversion of four facilities (seven units) to a biomass Power Plant; one of them, Atikokan, will start the operation in 2012.
· Nova Scotia is developing feasibility studies in Trenton power plant.
· To burn biomass for electricity production is considered “net zero” emission.
· The percentage of GHG emission reduction for the power plant is lower than the percentage of co-firing.
· To burn biomass has a SO2 emission reduction, the proportion depends of multiple factors; the relationship with NOx emission reduction is not clear.
· The use of biomass presents concern in ash deposition and fly.
· Conversion Coal power plant to co-firing biomass is considered a small capital investment to reduce GHG emission, compared to other technologies.
· Retrofit for co-firing for small power plant is more expensive; studies show a stabilization cost curve for power plant higher than 200 MW.
· The percentage of biomass co-firing has a optimal relationship which depends of multiple factors, low and high percentages show higher cost (COE and efficiency in capital investment)
· Higher market price of electricity will increase the additional costs of biomass co-firing. Thus greater incentives may be required for biomass co-firing if the market price of produced electricity is higher.
· The use of biomass in a coal power plants increase the cost of the produced electricity:
· Fuel biomass is not as efficient as coal; this means an increment between 10 to 30 % in the cost of the produced electricity
· increased corrosion rates of high temperature components decreases the time-live of the power plant
· incertitude in fuel price, transportation, price volatility, seasonal effects and quality increase the volatility in electricity production, then the COE.
· The estimated time to convert a Coal Power Plant to a co-firing biomass Power Plant is around 18 months.
· The job rate creation for co-fired biomass coal power plant is around one direct high paying job per MW.
· For big power plant conversion, the retrofitting cost is around M0.3 $CAD/MW
· For forestry industry, a mill which produces 70,000 tons of pellets per year could feed a 16 MW Power Plant or 10% co-firing biomass in a 160 MW Power Plant.
· To analyse the possibility to extend the life of the future decommissioned power plants through the conversion to co-firing/firing biomass
· Analyse the existent emission regulation and pollutant formation for this technology
· To work with stakeholders in Biomass retrofitting evaluation for sub-critical Pulverized Coal Power Plants
· To work with stakeholders in co-firing biomass retrofitting evaluation for all Pulverized Coal Power Plants
· Focus in future decommissioned Coal Fired Power Plants; second order focus in old Coal Fired Power Plants
· To work with stakeholders in the mapping of fuel availability and cost for each one of the projects before
· To work with stakeholders in possible agreements to minimize the barriers for co-fired biomass power plants
· Co-firing biomass in coal power plants help efficiently in GHG emission reduction
· It helps to extend the operative live of old coal plants
· It helps to develop communities, agriculture and forestry industries in Alberta
· The cost of the electricity increase with the use of co-firing biomass