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Energy generation and its use affect the surrounding environment. About sixty five percent of the energy comprises of global anthropogenic green house gas emissions which are renewable. Reduction of this emission must necessarily begin with action targeted shift of energy sources that are renewable. Out of the various sources of renewable energy biomass and specifically agro-biomass has a lot of potential as it can be utilized in the existing energy conversion systems with minor modification. Biomass can be utilized in energy conversion system by co-firing in a modern coal fired power plant with biomass content up to 10% by weight. The combustion efficiency of biomass feedstock can be about 10% lower than that for coal. Biomass can also be combusted in a dedicated power and combined-heat and power (CHP) plant that is typically smaller in size and of lower efficiency of up to 35%. In cogeneration mode the efficiency may go up to 90%.

Air-film cooled gas turbine is widely used in aero-derivative gas turbines. The present paper reviews previously developed air-film blade cooling models. The article further proposes a new blade cooling model for estimating blade coolant mass fraction which takes into account the effect of radiative heat transfer from hot flue gases to aero-derivative gas turbine blade surface. Various possibilities to achieve enhanced performance from aero-derivative gas turbine have been enumerated namely effect of advanced design philosophies, thermal barrier coatings, advancement in blade material. Also adoption of advanced design philosophies such as 3-D CFD would lead to improved component design. Further use of advanced blade material specifically for gas turbine blade application including single-crystal blade, directionally solidified blade material being nickel-chrome-molybdenum alloys may be explored.

In modern turboprop engines, reduction in emission and fuel consumption is the primary goals during the development of gas turbine aero engines. In this paper, a concept has been proposed for hybridizing the air blade cooled turboprop engines by integrating it with a fuel cell. The proposed study focuses on thermodynamic analysis of a turboprop engine integrated to a solid oxide fuel cell (SOFC) system. A solid oxide fuel cell is the perfect candidate for utilizing waste heat available at turboprop engine exhaust, through recuperation process. Integration of SOFC is ultimately leads to enhancement the overall performance of the turboprop-SOFC hybrid system. Power generated by the SOFC system can be utilized by the aircraft and in can complement the auxillary-power-unit (APU) and may even supplement it. On the basis of 1st and 2nd law of thermodynamic modeling analysis of a turboprop-SOFC system has been presented in this article.

Automotive power packs have been the focus of research over a long period of time. Among various power packs when we consider internal combustion engines, there is an ample opportunity in developing systems that can make optimal utilization of all the energy streams related to the automotive engine. In this regard utilization of internal combustion engine exhaust waste heat and environmental pollution have been the focus of research in the recent past. About 35% of the automotive input fuel energy is converted to useful crankshaft work and about 30% energy is expelled with exhaust. This leaves about one-third (35%) of the total energy that must be transmitted from the enclosed cylinder through the cylinder walls and head to the surrounding. The exhausted energy from engine results in entropy elevation and solemn environmental pollution. So it is desired to utilize waste heat to the extent possible.

Cogeneration involves simultaneous production of both thermal energy as well as electrical energy from a single energy conversion system. The thermal energy produced by the system is generally in the form of steam and generally used for process heating purposes. Marine gas turbine that provide propulsive power also have thermal energy in it exhaust gas stream which can be further be used to generate steam for process heating applications. Gas turbine blade cooling is critical to reliable operation of gas turbine based power utilities. A thorough literature review suggests that air-film cooling is one of the most widely used blade cooling techniques. The present study adopts few previously developed air-film cooling based gas turbine blade cooling models (without considering radiative heat transfer) and compare them with a proposed gas turbine model (which consider radiative heat transfer to gas turbine blade surface).

Increasing in the turbine rotor inlet temperature improves the aviation gas turbine efficiency, while on the other hand, but also leads to a higher requirement for blade cooling air, which in turn reduces the gain in efficiency achieved by increasing temperature. Turbine rotor inlet temperature has been increasing with the entry of highly-efficient gas turbines have been developed for the last decades for the aviation market. Around one fifth of the compressed air is extracted from the compressor and is used for blade cooling purposes and is thus not used in the actual power/thrust generation process, which has a negative impact on the engine efficiency. For this reason, new cooling methods and hot-gas path component materials that will be compatible with these high temperature’s gases are among the areas being analyzed.

An “APU” (Auxiliary Power Unit) is a small gas turbine engine to provide supplementary power to an aircraft and is located at the tails of larger jets. APU generators provide auxiliary electrical power for running aircraft systems on the ground. Applications include powering environmental systems for pre-cooling or preheating the cabin, and providing power for crew functions such as preflight, cabin cleanup, and galley (kitchen) operation and long-haul airliners must be started using pneumatic power of APU compressor. The Honeywell 131-9A gas turbine APU has 440 kW shaft power and 90 kW electric generator consuming 120 kg fuel/hour. Hybrid power systems based on fuel cells are promising technology for the forthcoming power generation market. A solid oxide fuel cell (SOFC) is the perfect candidate for utilizing waste heat recovery. This case deals with waste heat recovery from fuel cell exhaust using Brayton cycle as bottoming cycle for additional power production.

In the present scenario, when the non-conventional energy resources are still under development stage for their full potential as a source of energy for our fast growing population, gas turbines are one of the most promising power generation technologies. The gas turbine based power utilities are also gaining acceptance across globe, because of increase in extraction of natural gas. Further reduction in the price of natural gas would also result in the number of gas turbine units installed across globe and thus it is important to carry out the environmental analysis of gas turbine based utilities. The gas turbines are employed in power generation in industries, aircrafts and marine propulsion units. The present exercise carries out thermodynamic performance analysis i.e. energy, exergy and emission performance analysis of an air-craft gas turbine. The gas turbine blades of present cycle are assumed to be cooled by air-film blade cooling technique.

This paper focuses on the thermodynamic analysis of Solid Oxide fuel cell (SOFC). In the present work the SOFC has been modeled to work with internal reforming of fuel which takes place at high temperature and direct energy conversion from chemical energy to electrical energy takes place. The fuel-cell effluent is high temperature steam which can be used for co-generation purposes. Syn-gas has been used here as fuel which is essentially produced by steam reforming of methane in the internal reformer of the SOFC. A thermodynamic model of SOFC has been developed for planar cell configuration to evaluate various losses in the energy conversion process within the fuel cell. Cycle parameters like fuel utilization ratio and air-recirculation ratio has been varied to evaluate the thermodynamic performance of the fuel-cell. Output performance parameters like terminal voltage, cell-efficiency and power output have been evaluated for various values of current densities.

An “APU” (Auxiliary Power Unit) is a small gas turbine engine to provide supplementary power to an aircraft and is located at the tails of larger jets. APU generators provide auxiliary electrical power for running aircraft systems on the ground. Applications include powering environmental systems for pre-cooling or preheating the cabin, and providing power for crew functions such as preflight, cabin cleanup, and galley (kitchen) operation and long-haul airliners must be started using pneumatic power of APU compressor. The Honeywell 131-9A gas turbine APU has 440 kW shaft power and 90 kW electric generator consuming 120 kg fuel/hour. Here the traditional combustor of the APU is proposed to be replaced by a chemical-looping-combustion (CLC) system.