Performance and economy of the hottest E-type and

Comparison of performance and economy between E-type and F-type gas turbine combined cycle power plants

Yang Bai 1, Huang Jie 2

(1. Huizhou power plant preparation office, Huizhou 516080, Guangdong;

2. Shenzhen Guangqian Electric Power Co., Ltd., Shenzhen 518051, Guangdong)

e-type and F-type gas turbines refer to gas turbines with an inlet temperature of 1150 ℃ and 1350 ℃ respectively. The power plants with these two gas turbines as power units are called E-type gas turbine power plants and F-type gas turbine power plants respectively. To compare the two power plants, the first is to analyze and compare the two gas turbines, so as to further compare the efficiency, floor area and economy of the power plant. Through such analysis and comparison, it can help the builders of gas turbine power plants choose the unit model and provide them with certain reference and analysis methods

1 comparison of gas turbine structure and performance

Table 1 shows the latest performance data and structural characteristics of e-type and F-type gas turbine produced by the world's four major gas turbine manufacturers. These performance data are quoted from the 1999 ~ 2000 world gas turbine manual, which is based on ISO working conditions and uses natural gas as fuel. It can be seen from table 1 that the efficiency of type F gas turbine is about 4% higher than that of type E under design conditions; The total output power of type F is about 1.5 times that of type E; The unit output power is about 1.3 times. It can be seen that the performance of type F gas turbine is far better than that of type e gas turbine

2 comparison of performance and economy of combined cycle power plant

let's take a look at the performance characteristic diagram of gas turbine and its combined cycle. Figure 1 shows the relationship between gas turbine efficiency and pressure ratio at different combustion temperatures without charging management fees. Figure 2 shows the relationship between unit efficiency and pressure ratio at different temperatures during combined cycle. It can be seen from Figure 1 and Figure 2 that with the increase of combustion temperature, the efficiency of gas turbine and its combined cycle unit has been significantly improved, which is why everyone has been committed to studying high temperature resistant materials and advanced cooling technology to try to improve the initial temperature of gas turbine population. At the same time, it can also be seen from the relationship shown in Figure 1 and Figure 2 that the design pressure ratio of type E and f gas turbines is not selected according to the maximum thermal efficiency of the gas turbine, but according to the maximum unit output power; At this time, the efficiency permeability of the corresponding combined cycle is the highest under certain climatic conditions, that is, the gas turbine is designed according to the minimum energy consumption and maximum thermal efficiency of the combined cycle. Obviously, since the turbine inlet temperature of type e gas turbine is about 1150 ℃, which is about 200 ℃ lower than that of class F (1350 ℃), the efficiency of its corresponding gas turbine and its combined cycle is also significantly lower than that of class F gas turbine combined cycle. Next, we take s109e and S109FA of Ge as examples to analyze the differences in performance, space, construction cost and power cost of combined cycle power plants based on these two gas turbines

assuming that the rated capacity of the power plant is 1000 MW, working under ISO conditions, using natural gas as fuel, the unit operates for 4000 hours a year, and the fuel price to the plant is 0.198 US dollars/kg. Under the above working conditions, the performance of the unit is shown in Table 2. In Table 2, the output of type E is about 1/2 of that of type F, and the heat consumption is about 10% more. It can be seen that the performance varies greatly. Therefore, in order to meet the 1000 MW capacity of the power plant, six E-type units and three F-type units are required. Obviously, in terms of space, the installation of e-type units requires a larger land area. It is roughly estimated that the six E-type units need about 19000 m2, while the three F-type units only need about 14300 m2, that is, in terms of plant area, the F-type saves about 4700 m2 of land than the E-type. It is conceivable that the increase of land occupation will inevitably lead to the increase of land acquisition, civil engineering, slope, site preparation and infrastructure costs, resulting in the increase of power plant construction costs. Even from the construction cost of a complete single shaft power plant provided in the "1999 ~ 2000 world gas turbine manual to apply specific tension load to wire samples fixed in rotary collets and translational collets with specified working length (gauge length)" (obviously, this statistical cost cannot include civil engineering, land use, infrastructure and other inputs), The construction costs of GE's s109e and S109FA are $90million and $139 million respectively; For a 1000 MW power plant, the cost is about $540million and $417 million. It can be seen that the cost of building a 1000 MW power plant of type E is about US $123million higher than that of type F. From this point of view, type F also has obvious advantages over type E

let's take a look at the comparison of power cost. The so-called power cost refers to the input cost relative to the power generation, mainly including capital cost, fuel cost, operation and maintenance cost. The capital cost of each unit depends on the capital investment cost, annual interest rate, depreciation period and annual power generation; The fuel cost of each unit is proportional to the fuel price and the heat consumption of the power plant; Operating costs include fixed costs of operation, maintenance and administration and variable costs of component repair and replacement. The calculation formula of power cost is as follows:

where: Ce - power cost, and the wrong interface of USD/M may damage the equipment; Wh；

cci -- capital investment cost, 100000 US dollars

Ψ——— Annual capacity factor, Ψ＝｛ L · (1 + L) n}/{(1 + L) n － 1}, where l is the annual interest rate, assumed to be 0.075, n is the depreciation period, assumed to be 20 A

pae - annual power generation, MWh; RH -- heat consumption, J/wh

cf -- fuel price, USD/kg

&n