Biomass Gasification — Commercialization and Development: The Combined Heat and Power (CHP) Option

Author(s):  
Richard L. Bain ◽  
Kevin C. Craig ◽  
Ralph P. Overend

World-wide, biomass is the most used nonfossil fuel and is expanding from its traditional thermal applications to more usage for liquid fuels and electricity. More than 9 gigawatts of biomass electrical generation capacity have been installed in the United States, primarily by forest products industries, since the Public Utilities Regulatory Policy Act (PURPA) was passed. Combined heat and power (CHP) technologies promise to improve power-to-heat efficiencies to strengthen the economic viability of these electrical generating methods. These technologies, which are now being tested and demonstrated, employ industrial and aeroderivative gas turbines; use a variety of feedstocks including agricultural wastes, residues, and dedicated energy crops; and range in size from 8 MW to 75 MW. Specific demonstrations with the U.S. Department of Energy Biomass Power Program and partners in Vermont and Hawaii are discussed.

1995 ◽  
Vol 117 (3) ◽  
pp. 424-431
Author(s):  
A. Saith ◽  
P. F. Norton ◽  
V. M. Parthasarathy

The Ceramic Stationary Gas Turbine (CSGT) Program has utilized the SPSLIFE computer code to evaluate the preliminary design of ceramic components. The CSGT program is being performed under the sponsorship of the United States Department of Energy, Office of Industrial Technology, to improve the performance of stationary gas turbines in cogeneration through the selective replacement of hot section components with ceramic parts. Preliminary design evaluation and life assessment results are presented here for the following components: (1) Stage 1 turbine blade, (2) Stage 1 turbine nozzle, and (3) combustor inner liner. From the results of the analysis, recommendations are made for improving the life and reliability of the components. All designs were developed in Phase I (preliminary design) of the CSGT program and will be optimized in Phase II (detail design) of the program.


Author(s):  
Arun Saith ◽  
Paul F. Norton ◽  
Vijay M. Parthasarathy

The Ceramic Stationary Gas Turbine (CSGT) Program has utilized the SPSLIFE computer code to evaluate the preliminary design of ceramic components. The CSGT program is being performed under the sponsorship of the United States Department of Energy, Office of Industrial Technology, to improve the performance of stationary gas turbines in cogeneration through the selective replacement of hot section components with ceramic parts. Preliminary design evaluation and life assessment results are presented here for the following components: (1) Stage 1 Turbine Blade, (2) Stage 1 Turbine Nozzle, and (3) Combustor Inner Liner. From the results of the analysis, recommendations are made for improving the life and reliability of the components. All designs were developed in Phase I (preliminary design) of the CSGT program and will be optimized in Phase II (detail design) of the program.


Author(s):  
Jeffrey R. Price ◽  
Oscar Jimenez ◽  
Les Faulder ◽  
Bryan Edwards ◽  
Vijay Parthasarathy

A program is being performed under the sponsorship of the United States Department of Energy, Office of Industrial Technologies, to improve the performance of stationary gas turbines in cogeneration through the selective replacement of metallic hot section components with ceramic parts. The program focuses on design, fabrication, and testing of ceramic components, generating a materials properties data base, and applying life prediction and nondestructive evaluation (NDE). The development program is being performed by a team led by Solar Turbines Incorporated, and which includes suppliers of ceramic components, U.S. research laboratories and an industrial cogeneration end user. The Solar Centaur 50S engine was selected for the development program. The program goals included an increase in the turbine rotor inlet temperature (TRIT) from 1010°C (1850°F) to 1121°C (2050°F), accompanied by increases in thermal efficiency and output power. The performance improvements are attributable to the increase in TRIT and the reduction in cooling air requirements for the ceramic parts. The ceramic liners are also expected to lower the emissions of NOx and CO. Under the program uncooled ceramic blades and nozzles have been inserted for currently cooled metal components in the first stage of the gas producer turbine. The louvre-cooled metal combustor liners have been replaced with uncooled continuous-fiber reinforced ceramic composite (CFCC) liners. Modifications have been made to the engine hot section to accommodate the ceramic parts. To-date all first generation designs have been completed. Ceramic components have been fabricated, and are being tested in rigs and in the Centaur 50S engine. Field testing at an industrial co-generation site was started in May, 1997. This paper will provide an update of the development work and details of engine testing of ceramic components under the program.


Author(s):  
George A. Hay ◽  
Art Cohn ◽  
Paul Baustista ◽  
George Touchton ◽  
William Parks ◽  
...  

This paper summarizes the proceedings of the 1995 workshop in San Francisco, CA on “Small Gas Turbines for Distributed Generation” and the planned winter of 1996 follow-on workshop. The working definition for distributed generation used in the workshop was modular generation (generally 1–50 MW) in various applications located on electric customers sites or near load centers in an electric grid. The workshop was sponsored by the Electric Power Research Institute (EPRI), the Gas Research Institute (GRI), the U.S. Department of Energy (DOE) and Pacific Gas and Electric (PG&E). The objectives were to: • review historical operating experience, market trends and the current state of the art of small gas turbine based options (1–50 MW size range); • characterize benefits, motivations, application requirements and issues of small gas turbines in distributed generation strategies amongst “stakeholders”; • identify what further efforts, technology or otherwise, should be pursued to enhance future opportunities for small gas turbine “stakeholders’; and • define “stakeholder” interest in future forums for coordination and discussion of improved distributed generation strategies based on small gas turbines. The workshop was attended by over 42 electric or gas utilities, 12 independent power companies and a broad cross section of equipment suppliers. Architect and Engineers (A&E’s), Research Development and Demonstration (RD&D) programs, government organizations, international utilities and other interested parties. The total workshop attendance was over 140. Small gas turbine technologies, user case histories, operating experiences, electric and gas system requirements, distributed generation economic theory, regulatory issues and general industry perspectives were reviewed. Industry input was gathered through a formal survey and four break-out sessions on future small gas turbine user needs, market requirements and potential hurdles for distributed generation. Presentations by suppliers and users highlighted the significant commercial operating experience with small gas turbines in numerous electric utility and non-electric utility “distributed” generation applications. The primary feedback received was that there is significant and growing market interest in distributed generation strategies based on small gas turbines options. General consensus was that small gas turbine systems using natural gas would be the technology of choice in the United States for much of the near-term distributed generation market. Most participants felt that improved gas turbine technology, applications and distributed generation benefit economic evaluation models could significantly enhance the economics of distributed generation. Over 30 utility or other users expressed support for the formation of a small gas turbine interest group and an equal number expressed interest in hosting or participating in demonstration projects. A strong interest was indicated in the need for a follow-on workshop that would be more applications focused and provide a forum for coordinating research activities. Current plans by EPRI, GRI and DOE will be to include the follow-on as part of a planned workshop on “Flexible Gas Turbine Strategies” in the fall of 1996.


Author(s):  
Scott J. Curran ◽  
Timothy J. Theiss ◽  
Michael J. Bunce

Pending or recently enacted greenhouse gas regulations and mandates are leading to the need for current and feasible GHG reduction solutions including combined heat and power (CHP). Distributed generation using advanced reciprocating engines, gas turbines, microturbines and fuel cells has been shown to reduce greenhouse gases (GHG) compared to the U.S. electrical generation mix due to the use of natural gas and high electrical generation efficiencies of these prime movers. Many of these prime movers are also well suited for use in CHP systems which recover heat generated during combustion or energy conversion. CHP increases the total efficiency of the prime mover by recovering waste heat for generating electricity, replacing process steam, hot water for buildings or even cooling via absorption chilling. The increased efficiency of CHP systems further reduces GHG emissions compared to systems which do not recover waste thermal energy. Current GHG mandates within the U.S Federal sector and looming GHG legislation for states puts an emphasis on understanding the GHG reduction potential of such systems. This study compares the GHG savings from various state-of-the-art prime movers. GHG reductions from commercially available prime movers in the 1–5 MW class including, various industrial fuel cells, large and small gas turbines, micro turbines and reciprocating gas engines with and without CHP are compared to centralized electricity generation including the U.S. mix and the best available technology with natural gas combined cycle power plants. The findings show significant GHG saving potential with the use of CHP. Also provided is an exploration of the accounting methodology for GHG reductions with CHP and the sensitivity of such analyses to electrical generation efficiency, emissions factors and most importantly recoverable heat and thermal recovery efficiency from the CHP system.


Extensive laboratory and pilot plant experimental work on the Solvent Refined Coal process by Gulf Oil Corporation over the past 18 years, sponsored by the Fossil Fuel Division of the United States Department of Energy and its predecessor agencies, has led to the development of an improved version of the process known as SRC-II. This work has shown considerable promise in recent years and plans are now being made to demonstrate the SRC-II process with commercial size equipment in a 6000 ton/day (5440 t/day) plant to be located near Morgantown, West Virginia. On the basis of recent economic studies, the products (both liquid and gas) from a future large-scale commercial plant are expected to have an overall selling price of $4.25-4.75/GJ (first quarter 1980 basis). The major product of the primary process is distillate fuel oil of less than 0.3 % sulphur for use largely as a non-polluting fuel for generating electrical power and steam, especially in the east where utilities and industry are currently using petroleum products. In such applications, SRC-II fuel oil is expected to be competitive with petroleum-derived fuels within the next decade. During this period, SRC-II fuel oil should be economically attractive compared with coal combustion with flue gas desulphurization in electric utility and industrial boilers, particularly in the major metropolitan areas. Naphtha produced by the SRC-II process can be upgraded to a high-octane unleaded gasoline to supplement petroleum-derived supplies. Significant quantities of pipeline gas are also produced at a cost that should be competitive with s.n.g. from direct coal gasification. Light hydrocarbons (ethane, propane) from the process may be effectively converted to ethylene. In addition, certain fractions of the fuel oil might also be used in medium-speed diesel engines and automotive gas turbines. For many of these applications, the fuel oil and other products from the SRC-II process would displace high-quality petroleum fractions, which could then be used for production of diesel fuels, jet fuels, home heating oil and gasoline by conventional refinery processes.


Author(s):  
D L Tolley ◽  
G J Fowler

This paper examines the impact of the Public Utilities Regulatory Policies Act (PURPA) in the United States and the Energy Act 1983 in the United Kingdom on the nature of the purchase tariffs for co-generators and combined heat and power (CHP) plant, and considers the reasons why the prospects for investment by private generators might be enhanced in the United States.


Author(s):  
Paul F. Norton ◽  
Gary A. Frey ◽  
Hamid Bagheri ◽  
Aaron Flerstein ◽  
Chris Twardochleb ◽  
...  

A program is being performed under the sponsorship of the United States Department of Energy, Office of Industrial Technology, to improve the performance of stationary gas turbines in cogeneration through the selective replacement of hot section components with ceramic parts. It is envisioned that the successful demonstration of ceramic gas turbine technology, and the systematic incorporation of ceramics in existing and future gas turbines will enable more efficient engine operation, resulting in significant fuel savings, increased output power, and reduced emissions. The engine selected for the program, the Centaur 50 (formerly named Centaur ‘H’) will be retrofitted with first stage ceramic blades, first stage ceramic nozzles, and a ceramic combustor liner. The engine hot section is being redesigned to adapt the ceramic parts to the existing metallic support structure. The program currently in Phase II focuses on detailed engine and component design, ceramic component fabrication, ceramic component testing, establishment of a long term materials property database, and the development and application of supporting technologies in the areas of life prediction and non-destructive evaluation. This paper outlines the design activities associated with the introduction of a ceramic first stage nozzle and two configurations of ceramic first stage turbine blade. In addition, probabilistic life assessment of the ceramic parts for major failure modes (fast fracture, slow crack growth and where relevant, creep and oxidation) will be discussed.


Author(s):  
Sy A. Ali ◽  
Robert R. Moritz

Aero-derivative gas turbines have been successfully serving the power generation, mechanical drive, and marine markets for 40 years. These products are well suited for distributed generation, with sizes in the range from 3 MW to 50+ MW. The Rolls-Royce group of companies provide vertical integration for aero-derivative based energy systems, having marketing, sales, manufacturing, packaging, distribution, and customer service capabilities. The 3– 6 MW, 501-K family serves power generation and cogeneration applications. The new 6–8 MW 601 is used for cogeneration and mechanical drive. The 15 MW Avon is widely applied to mechanical drives, offering exceptional reliability and low life cycle cost. The RB211 provides over 30 MW at high efficiency, and is used in mechanical drive and electrical generation. The 42% efficient, 50 MW, Trent is primarily intended for electrical generation. This engine retains a higher than usual degree of commonality with aero production modules, thus retaining the cost advantage of high volume production and benefits from continuous improvements in aero engines. Plans: Cost reduction of mature existing products will be achieved by “industrialization”, e.g. by alloy changes and shape simplification, of parts no longer in aero production. Better integrated packaging and “more electric aircraft” features are rapidly becoming a necessity in the competitive marketplace. The trend is toward minimizing and possibly eliminating mechanical drives and other components in a gas turbine to improve product quality, efficiency, reduce product cost, while enhancing product quality and the environment. In this regard, the approach being taken near term is to substitute normal oil bearings with Active Magnetic Bearings. Such an action would help eliminate high cost skid lubrication system components and some environmental hazards as well as reducing maintenance. Several programs will make contributions to environmental improvements through reduced emissions and the use of “renewable” fuels. A prototype 501-K has been supplied to operate on gasified coal, a reduced emissions path to generating electricity from coal. A dual fuel DLE combustion system for very high pressure ratio and turbine temperature is in development for the Trent, having downward compatibility with other company products. The Next Generation Gas Turbine (NGGT) project, sponsored by the US Department of Energy, will use an existing engine core. Advanced modules, including a long life “spiral” recuperator and cycle enhancements combine to yield 50% cycle efficiency at a reduced cost per kW. The goal is to produce a 50 MW class plant with “combined cycle efficiency at simple cycle cost.” The NGGT is suited to using alternate fuel for part of the energy input. Following evaluation of fuel cell/gas turbine hybrids, a specially suited gas turbine development is being initiated with sponsorship by the U.S. Department of Energy. The company is also conducting a solid oxide fuel cell program. An auxiliary power unit(APU) was developed and is now in production for the M1 tank. A “microturbine” derivative of this product is being considered for distributed generation.


Author(s):  
Oscar Jimenez ◽  
John McClain ◽  
Bryan Edwards ◽  
Vijay Parthasarathy ◽  
Hamid Bagheri ◽  
...  

The goal of the Ceramic Stationary Gas Turbine (CSGT) Development Program, under the sponsorship of the United States Department of Energy (DOE), Office of Industrial Technologies (OIT), is to improve the performance (fuel efficiency, output power, and exhaust emissions) of stationary gas turbines in cogeneration through the selective replacement of hot section components with ceramic parts. This program, which is headed by Solar Turbines Incorporated and supported by various suppliers, and national research institutes, includes detailed engine and component design, procurement, and field testing. A major challenge in the successful introduction of ceramic parts into a gas turbine is the design of the interface between the ceramic parts and metallic hardware. A turbine blade, which incorporated a dovetail root, was designed with such considerations. A relatively thin compliant layer between the ceramic-metallic loading surface was considered for equalizing pressure face load distributions. Five monolithic siliocn nitride ceramic materials were considered: AS800 and GN10, AlliedSignal Ceramic Components; NT164, Norton Advanced Ceramics; SN281 and SN253, Kyocera Industrial Ceramics Corporation. The probability of survival using NASA/CARES for 30,000 hours of engine operation was calculated for each material. The blade frequencies, stresses, and temperatures were predicted. The influence of the dovetail angle was also analyzed to determine the most optimum configuration. Prior to engine installation all blades underwent extensive nondestructive evaluation and spin proof testing. This paper will review the design, life prediction, and testing of the first stage ceramic turbine blade for the Solar Turbines Centaur 5OS engine.


Sign in / Sign up

Export Citation Format

Share Document