By Jane Todd
Ontario is promoting more renewable electricity generation and conservation through the Green Energy Act. Biomass represents one renewable electricity option for the province.
By Jane Todd
Ontario is promoting more renewable electricity generation and conservation through the Green Energy Act. Biomass represents one renewable electricity option for the province. In addition, by converting existing Ontario Power Generation (OPG) coal-fuelled generating units, it is renewable electricity that can be produced on demand when it is needed. These are all good reasons why OPG is exploring the biomass option.
Why else biomass? Biomass fuels are recognized around the world as renewable, provided that they are obtained from sustainable sources. Biomass fuels are also considered to be carbon neutral: the amount of greenhouse gases (GHGs) emitted during combustion is equal to the GHGs absorbed while the material was growing. This gives biomass a major environmental advantage over fossil fuels such as coal, oil, and natural gas. A 2008 University of Toronto study of lifecycle emissions associated with Ontario wood pellets, coal, and natural gas found that generating electricity with 100% biomass reduced GHGs by 90% compared to coal and 75% compared to combined-cycle natural gas.
Although delivering environmental benefits, biomass-generated electricity will require a price that reflects its higher costs. Biomass production and processing, fuel transportation, storage, and handling costs will be a significant part of the costs of biomass energy production. Typically, biomass fuels are more expensive than coal per unit of energy produced.
The actual costs will vary depending on the type of biomass, as well as financing, location, and production system design. For example, the energy content of biomass varies by biomass type. Wood pellets tested at Atikokan Generating Station (GS) in northwestern Ontario have a heat value greater than lignite coal, which is Atikokan’s current fuel. In contrast, wheat shorts, tested at Nanticoke GS, have about 50% of the energy value per kilogram compared to bituminous coal.
Under provincial regulations, OPG will have to phase out the use of coal by the end of 2014. These generating stations are owned by the people of Ontario, and conversion to biomass could ensure they are used well into the future. Take Atikokan GS, which came online in November 1985 at a cost of $750 million. It has been well maintained over the years and is supported by transmission lines, transportation infrastructure, trained staff, and an enthusiastic community that sees the biomass initiative as a catalyst for a bigger and better tomorrow.
Concept studies for the conversion of Atikokan GS to biomass have been completed, and preliminary engineering is underway for combustion modifications and facilities required for the safe handling and storage of biomass pellets. OPG’s target date for conversion of Atikokan to biomass is 2012. However, before it can start the process for procuring the fuel and before starting the conversion of the plant to burn biomass, an agreement with the Ontario Power Authority to purchase power from the converted station is required.
Concept studies are also underway for OPG’s Nanticoke GS and Thunder Bay GS. Similar studies for Lambton GS will begin in the next few months. OPG is also conducting research on combustion, ash use potential, and environmental characteristics for a range of agricultural biomass and wood biomass fuelling options.
OPG continues to research the environmental benefits of biomass. A study of the lifecycle of GHG emissions is being commissioned for agricultural biomass sources in conjunction with the Ontario Ministry of Agriculture, Food, and Rural Affairs. The study will document the typical net GHG benefit of using agricultural biomass when emissions associated with planting, harvesting, processing, and transportation are considered.
OPG is developing specifications for a reliable and sustainable pelletized biomass fuel supply for Atikokan GS and the other proposed plants. Options for transporting pellets to Atikokan GS are being considered. As well, details for covered storage on site are being worked out. A transportation consultant has been engaged to optimize the transportation and storage logistics of biomass delivery to the plant.
The development of a biomass fuel supply could be the catalyst for a made-in-Ontario industry providing opportunities for the forest industry and agricultural sector. Converting generating units at OPG’s coal-fired plants to biomass fuel supports Ontario’s move to more renewable electricity and is important for the communities in which they operate.
OPG will continue to work with the forestry and agriculture industries, the academic community, and government ministries and agencies to develop biomass opportunities. Although there are many challenges ahead, OPG’s biomass team continues to make encouraging progress.
Jane Todd is program manager for Ontario Power Generation’s Northwest Fossil division and a director of Canbio.