Realizing Plants’ Full Potential: Electricity from Biomass By Becky Schanz and Megan Garvey Chicago-Kent College of Law Energy Law Presentation* email@example.com firstname.lastname@example.org
Overview of Presentation • Introduction and Background • Technologies that Produce Electricity from Biomass • Legal Aspects • Conclusion
Biomass: • Biomass is plant matter or other biological material, such as trees, grasses, or agricultural crops. • On average, biomass is made of 75% carbohydrates and 25% lignin. • Lignin forms the woody cell walls of the plants.
Biomass • Wood and Wood products
Biomass • Agricultural Biproducts and Residues
Biomass • Trees, shrubs, grasses and other energy crops • Typically fast growing
Bioenergy: • Bioenergy or biomass energy is any fuel, electric power, or useful chemical product derived from organic matter. • Bioenergy can be derived either directly from the plants or indirectly from plant-derived wastes and residues.
Environmental Factors • Generates same amount of heat and carbon dioxide as from natural processes. • Renewable energy source • Reduces erosion by preserving soil
Environmental Factors • Provides a habitat for wildlife species • Provides moisture retention and shade, which cools our atmosphere. • Most wood used is remnants from the logging industry, such as tree tops and wood chips.
Reliability • The United States has an estimated 65-90 billion tons of dry matter. • At 2000 energy use levels, this biomass could supply 14-19 years of energy. • The Department of Energy states that all of the biomass available now has an energy content that would produce an estimated 2,740 Quads. • 1 Quad = 1,000,000,000,000,000 Btus
US Biomass Generation • The US is the largest biopower generator. It produces 37 billion kWh of biomass electricity which requires about 60 million tons of biomass a year. • The US has more than 7,000 MW of installed capacity. • We have about $15 billion invested and 66,000 jobs.
Marketing & Incentives • Green Power Marketing provides choices for consumers to purchase power from renewable or environmentally friendly sources. • Customers also pay a premium to support investment in renewable energy technologies.
Marketing & Incentives • The EPA Combined Heat and Power Partnership program is a voluntary partnership between EPA, combined heat and power (CHP) industry, utilities, and state and local governments that create CHP programs.
Biomass Uses for Energy • Heating – stoves, process heat • Cooking – developing world • Transportation – ethanol • Electric Power Production
Technologies used to Produce Electricity from Biomass • Direct Combustion - burning biomass with excess air to produce steam
Technologies (cont.) • Co-Firing – replaces part of the coal with biomass, as a supplementary energy source.
Technologies (cont.) • Gasification – heat biomass without oxygen to produce a calorific gas
Technologies (cont.) • Small Modular Bio-Power – develops small, efficient, clean biopower systems
Direct-Fired Combustion • Oxidation of air and biomass • Produces hot flue gases that produce steam • Steam generates electricity in generators
Small-Modular Systems • Less than 5 MW • Potential to power villages • Consist of power generation attached to the transmission and distribution grid, which is close to the end consumer. • Potential to supply 2.5 billion people who are currently without electricity.
Gasification • Two processes: • Pyrolysis – releases volatile compounds of the fuel • Bigger role here than in coal fired plants • Char Conversion – carbon remaining after pyrolysis reacts with steam and/or oxygen (combustion) • Biomass has high reactivity
Types of Gasifiers • Direct Gasifier • Indirect Gasifier
Gasification Process – Direct Gasifier • Plant gets wood chips • Biomass is gasified • Air is extracted from the gas turbine and fed into the gasifier • Gasification steam is extracted. • Remaining fuel gases are cooled.
Gasification Process – Direct Gasifier • Fuel gas combusts and produces electric power and a high temperature exhaust steam • Exhaust steam expands in a steam turbine to produce additional power • Steam is extracted and electricity is sent to a substation
Generating Capacity • The United States has about 7 GW of grid-connected biomass generating capacity. • Coal-fired electric units are 297 GW of capacity, which is about 43% of total generating capacity.
Vermont Project • Vermont has the first industrial biomass gasification process located in Burlington. • The process integrates a high-throughput gasifier with a high-efficiency gas turbine. • Circulating hot sand surrounds the biomass particles and the particles break down and produce gas. • This project uses an indirect gasifier system.
Hawaii Project • Hawaii Biomass Gasifier is part of the DOE’s initiative to demonstrate a gasification system to turn biomass into electricity. • Its goal is to provide competitive electric power. • The plant uses maple wood chips, California highway clippings, paddy rice straw, fuel from refuse, bark, paper mill sludge, and alfalfa. • This project uses a direct gasifier system.
Advantages of Gasification • Biomass closes the carbon system and therefore reduces emissions. • Biomass is low in sulfur • Biomass contains .05 to .20 % of weight is sulfur • Coal contains 2-3% of weight is sulfur
Advantages of Gasification • Operates at a lower temperature and wider variety of feedstocks than direct combustion systems. • Can produce a Btu gas that is interchangeable with natural gas. • Produces nitrogen free gas. • Less landfill waste. • Future technologies are being developed • Fuel Cell Systems
Disadvantages of Gasification • Some biomass plants have closed because of deregulation of the electric utility industry. • Hard to compete with cheaper sources, such as coal, oil, and nuclear. • Small amounts of tar are released in the gas. The tar can coat parts of the pipe or the equipment. • Catalyst reactor has been developed to decrease the amount of tar to parts-per-million.
Disadvantages of Gasfication • Still a new technology and the Vermont Plant has not been able to operate continuously yet for a sustained period of days or weeks. • Over storage of wood fuel can lead to odor problems and spontaneous combustion.
Costs • Capital costs of building a biomass-fired steam turbine plant is about $2000-2500 per KW of installed capacity. • These costs are expected to decrease in the future.
Future of Gasification • Gasification has a bright future, once the technology is fine-tuned. • If the cost of the process decreases as expected, it will be able to compete economically with current energy sources.
Co-Firing Biomass with Coal and the Legal/Governmental Incentives for Biomass as a Renewable
Co-firing Biomass with Coal to produce Electricity • What is Co-firing? • The simultaneous combustion of biomass and coal in a pre-existing boiler of a traditional coal-fired power plant • 2 Methods • Blending • (+) Least expensive • (-) Limited amounts; higher possibility of damage • Separate Feed • (+) greater emission reductions; greater amounts of biomass tolerates; less harmful to existing boiler • (-) requires more resources (equipment, $)
Advantages of Co-firing:“Something for Everyone” The Existing Power Plant • Existing equipment is still utilized • Easier to meet environmental regulations and hedge future regulations • Cost savings • Tax incentives • Fuel supply options • Good PR
Advantages of Co-firing:“Something for Everyone” Biomass • Encourages development of feedstock infrastructure • Creates a market for residues and energy crops
Advantages of Co-firing:“Something for Everyone” The Environment • Reduces GHG emissions (CO2; CH4) • Reduces SO2 and NOX emissions • Reduces burden on landfills • Extends the life of coal-use for electricity generation
Advantages of Co-firing:“Something for Everyone” The Economy $$$ • Provides an end use for low value/negative value products • Maintains existing market for coal • Increases domestic economic growth and job creation • Increase economic activity in rural/agricultural areas • Increase business for equipment suppliers
Disadvantages of Co-firing Technological issues • Existing boilers/systems designed (exclusively) for fossil fuels • Negative impact on existing boilers • CL-based corrosion • Negative impact on boiler capacity