Alternative Fuels: Reducing Fuel Costs and Greenhouse Gas Emissions
Posted: January 16th, 2012Author: All4 Staff
The use of alternative fuels for heat and power generation is on the rise, an increase that can be attributed to the price surge and volatility of traditional fossil fuels, as well as a general desire to use more environmentally friendly materials to reduce greenhouse gas emissions. Alternative fuels have been successfully permitted and are being effectively used on a consistent basis as fossil fuel substitutes at numerous public, commercial, and industrial manufacturing facilities. In addition to the “mainline” alternative fuels such as biodiesel and ethanol that receive plenty of press coverage, there are numerous less-visible alternative fuels that are being utilized more and more. Typical alternative fuels include:
- Biomass materials such as wood and wood waste, agricultural byproducts, crops and crop residue, grasses, biomass gasses (biogas), and liquids.
- Industrial byproducts such as petroleum refinery byproducts, biodiesel manufacturing byproducts, ethanol manufacturing byproducts, wood waste, tires, waste oils, waste plastics, waste paper, black liquor (from the pulp production process), paper fiber sludge, waste textiles, waste carpet, landfill gas, municipal solid waste, rendering plant residue, biosolids, and other various industrial byproducts with high energy value (5,000 Btu/lb).
There are many potential advantages to using alternative and biomass fuels as a substitute for fossil fuels for meeting energy needs. Specific benefits depend upon the intended use and fuel source. Benefits often include fuel cost savings, using a carbon-neutral fuel source or potentially reducing greenhouse gas and other air pollution reductions, local economic development, waste reduction, and the security of a domestic fuel supply. In most cases, the use of alternative fuels for heat and steam production will require the source to secure environmental permits.
Solid Waste Permitting
Alternative fuels can be permitted as a fuel option to be co-fired along with traditional fossil fuels in an existing industrial furnace or boiler, or can be permitted in a stand alone combustion device. Proper facility permitting of alternative fuel use involves a detailed examination of the intended receipt, storage, handling/processing, fuel chemical analysis, and combustion device. Additionally, a detailed review of state and Federal applicable regulations is required to determine the unique permit requirements which may be necessary to receive, store, process, and use a particular alternative fuel. In some instances, a solid waste permit, beneficial use permit, or co-product determination may be required to manage certain alternative fuels. Many states, including Pennsylvania, have promulgated General Permits which set specific conditions for the receipt, processing, and management of select alternative fuels (i.e., residual wastes) for use in industrial facilities. As you consider the use of alternative fuels, do not overlook the potential impact of Federal, state, and local solid waste regulations.
Air Quality Permitting
Some waste-derived alternative fuels, such as hazardous wastes and municipal wastes, are specifically regulated and must comply with existing stringent state and Federal requirements which regulate the combustion of these specifically defined materials. Other non-hazardous materials will need to be studied and permitted in a more traditional sense in accordance with specific state and local requirements. In all cases of alternative fuel combustion, facilities will need to evaluate the proposed alternative fuel use implications with respect to air quality permitting. Typically this evaluation will involve an estimate of the maximum potential emission rates of regulated air pollutants using the alternative fuel analytical data, available facility and vendor combustion device information, and other available references. New proposed uses of alternative fuels will typically require a new construction permit or the modification of an existing facility air permit. Prior to embarking on an alternative fuel project, it is recommended that a permitting strategy be developed for the specific fuel and combustion device to be reviewed with the relevant permitting authorities.
The use of alternative fuel as a fossil fuel substitute can be an attractive option for both large and small facilities. In fact, any facility that depends on electricity, natural gas, or fuel oil for heating or process steam needs is a prime candidate to investigate alternative fuels. The primary reason is economics. When fuel oil costs $2.00 per gallon and chipped wood costs $50 per ton, the use of wood fuel reduces energy costs by nearly 75%, making biomass-fueled systems economically attractive. Many other alternative fuels can be secured at costs less than the typical cost of chipped wood, making these fuels even more attractive. Here are a few specific examples:
- The Dillon Floral Company in Bloomsburg, PA is saving over $191,000 per year on fuel costs to heat their greenhouses by switching from a fuel oil-fired boiler to a wood-fired biomass boiler system.
- During the 2006 heating season, the Mountain View School District in Susquehanna County, PA saved $114,000 by heating with wood chips instead of No. 2 fuel oil.
- The Elk Regional Health Center is saving over $300,000 per year by switching from natural gas to biomass.
In addition, many pulp mills have been using wood fuel for years and are now modifying their operating permits to co-fire tires, waste paper, and other alternative fuels. Cement and lime kilns are investigating and are in various stages of permitting to allow the co-firing of glycerin, plastics, biosolids, and other alternative fuels in their kilns. Real and anticipated fuel savings at these large industrial furnaces and boilers range from several hundred thousand dollars per year to over $3,000,000 per year depending on the alternative fuel cost and permitted substitution rate.
Each proposed alternative fuel must be analyzed and evaluated on a case-by-case basis for specific exposure to humans and ecological receptors and environmental impacts during receipt, storage, and use. Generally speaking, the use of alternative fuels will tend to reduce overall air pollution emissions at the facility. Most, but not all, alternative fuels do not contain sulfur or contain sulfur at levels well below traditional fossil fuels. Most, but not all, alternative fuels contain only trace amounts, if any, of heavy metal contaminants, typically at levels significantly lower than fuel oil and coal. Biomass fuels (e.g., wood) are considered renewable fuels and, by definition, are carbon-neutral meaning that the use of renewable biomass fuels lowers the facility’s CO2 emissions equal to the displaced quantity of fossil fuel-related CO2 emissions. As more and more facilities begin to examine their carbon footprint, a common finding is that heating and energy use is their major greenhouse gas (GHG) emission contributor. By substituting renewable alternative fuels for heating or combined heat and power (CHP), a facility may be able to realize significant GHG reductions.
Alternative Fuel Systems
Alternative fuel energy systems can be thermal systems (i.e., combustion, gasification, and pyrolysis), biochemical systems (i.e., aerobic and anaerobic digestion), or a combination of systems. Modern biomass combustors are clean burning, meet current air emission standards, and in most cases can be incorporated into the facility’s process systems. The alternative fuel systems in use today are fully automated and use computerized methods to automatically move fuel from a storage bin “on-demand” to the burner and to continuously self-adjust the fuel feed rate and combustion conditions. Many stand alone systems are equipped with automatic de-ash systems which continuously remove any fuel ash from the units to an ash bin.
Biomass systems can be designed to meet the needs of the user and the available fuel source. Advanced Recycling Equipment, Inc. (ARE) manufactures biomass burner systems in their facility in St. Marys, PA. ARE has numerous systems in operation around the country and has recently commissioned a biomass unit at the National Renewable Energy Laboratory (NREL) in Golden, CO to provide heating for several NREL facility buildings. Visit ARE’s website to view standard components of a typical biomass combustion system and to view various applications in operation in the United States and abroad.
Numerous sources of funding assistance exist for alternative fuel/energy systems. State and Federal programs include grants, low interest loans, and renewable energy credit programs. A comprehensive source of information on state, local, utility, and Federal incentive programs supporting renewable energy and alternative (biomass) fuels can be found at the Database of State Incentives for Renewables and Efficiency.