Performance evaluation and case studies of microturbines fuelled with natural gas and diesel

Abstract

The high reliability and simple design of microturbines make them an attractive prime mover in the generation and distribution of electricity in the low capacity range. This paper gives an overview of microturbines in the Brazilian environment and provides a performance assessment and an economic analysis of these machines fuelled by natural gas and diesel and also an indication of their emission levels. This work was based on data that were obtained from experimental tests on microturbines operating at full and part load. The performance assessment indicated that it is possible to obtain up to 27 per cent microturbine efficiency at full load under local conditions. The nitrogen oxides (NO x ) and carbon monoxide (CO) emissions level of the machines tested are less than 7 ppmv@15%O 2 at full load when natural gas is the fuel. The units are therefore clean enough to be sited among residential and commercial establishments. The results of the economic analysis show that with the natural gas microturbine used in cogeneration, it is possible to achieve a payback time on capital equipment of less than 4 years. The return on the investment has improved with the favourable pricing policies of some of the natural gas distribution companies and with the rise in electricity prices in Brazil.

Impact of heat transfer on the performance of micro gas turbines

“…Whereas the monorotor type compressor and turbine assembly is the dominant configuration for power generation micro turbines, other configurations are also being pursued [2][3][4]7,46]. A configuration where the combustion chamber is mounted in between the compressor and turbine is for instance often found for small turbojet engines [36,47,48].…”

“…When designed for a power output of 5 to 15 kW, micro turbines are of interest for various commercial and military applications [1,[4][5][6][7][8]. They could provide the power for a household or a small set of units [1,4,6,9], or form the backbone of a distributed backup and peak demand system as they offer an unparalleled flexibility [1][2][3]6,[10][11][12][13].…”

“…They could provide the power for a household or a small set of units [1,4,6,9], or form the backbone of a distributed backup and peak demand system as they offer an unparalleled flexibility [1][2][3]6,[10][11][12][13]. This unique fuel flexibility makes them ideal for both remote power generation at off-grid locations as well as for operation on indigenous fuels in developing countries [2,7,11]. Micro turbines are attractive prime movers as they offer a good power quality, a very high reliability, a long engine life and low maintenance costs [2,4,7,11,12,14].…”

“…This unique fuel flexibility makes them ideal for both remote power generation at off-grid locations as well as for operation on indigenous fuels in developing countries [2,7,11]. Micro turbines are attractive prime movers as they offer a good power quality, a very high reliability, a long engine life and low maintenance costs [2,4,7,11,12,14]. They produce low noise and vibrations as well as very low emission levels and are thus well suited for domestic use [2,6,10].…”

Microturbine Design Point Evaluation and Optimization Considering Pollutant Emissions and Thermoeconomic Approach

“…It is necessary to consider more carefully the economic and the environmental aspects [10]. Fuel consumption has a great influence on cost and environmental impact, justifying the search for more efficient engines, such as the recuperated types, to maintain the compromise between lightweight and low emissions, as required for small microturbines in the actual DG market [11,12].…”