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Analysis of the advantages and disadvantages of condensing steam turbines. As the core power equipment in modern thermal power generation, condensing steam turbines hold a pivotal role in global power systems thanks to their mature thermal cycle technology. It creates a highly vacuum environment by installing a condenser at the exhaust side, allowing steam to condense at extremely low pressures after performing work, thereby maximizing the efficiency of converting thermal energy into mechanical energy. However, while this technical approach offers significant advantages, it also has notable limitations that need to be considered in conjunction with specific application scenarios for a comprehensive evaluation. In terms of technical advantages, the core competitiveness of condensing steam turbines lies in two aspects: thermal efficiency and economic viability. Since the condenser can maintain the exhaust steam pressure at a level far below atmospheric pressure (usually 4–7 kPa), the available enthalpy drop of the steam increases significantly, allowing more work to be produced per unit mass of steam. This feature directly reduces the coal consumption per unit of power, and the advantage in thermal efficiency is even more pronounced in large-capacity units of 300 MW and above. At the same time, this model possesses the technical feasibility to develop supercritical units with capacities of millions of kilowatts; its maximum unit capacity far exceeds that of back-pressure or extraction steam turbines, enabling it to meet the stability requirements for base-load operation in power grids. Furthermore, a sophisticated vacuum system and condensate recovery mechanism not only ensure the high-purity recycling of working fluids and reduce the costs associated with treating make-up water, but also enable stable load regulation to accommodate long-term, continuous full-load operation. However, its technical flaws are equally significant. Firstly, its large number of auxiliary systems represent its inherent weaknesses: the need for equipment such as condensers, circulation water pumps, exhaust systems, and cooling towers results in a large footprint and high system complexity, leading to high initial investment and maintenance costs. Secondly, the high dependence on vacuum poses a potential risk to operational safety – for every 1 kPa decrease in vacuum level, the heat consumption of the unit increases by 1.5% to 2.0%, accompanied by issues such as rising exhaust steam temperature and increased axial thrust; in severe cases, this can lead to equipment damage. More critically, all the waste heat from the exhaust gas is discharged into the environment through a cooling medium (water or air), making it impossible to achieve cogeneration; as a result, the overall energy utilization rate of the plant is limited to the 40%–45% range, which is far lower than that of combined cycle or heating units. Furthermore, startup procedures such as warming up and vacuuming take a long time, and efficiency declines significantly under variable operating conditions, making it difficult for them to meet the demands of power grids that require frequent start-stop operations or deep load regulation. In summary, condensing steam turbines are typical power generation units that prioritize efficiency and large scale; their high thermal efficiency and large capacity make them well-suited for use as base-load power sources. However, issues such as system complexity, waste of waste heat, and limited operational flexibility restrict their application in distributed energy systems or for peak-shaving purposes. Future technological improvements need to focus on breakthroughs in vacuum optimization, cascaded utilization of waste heat, and rapid start-up and shutdown to balance the trade-off between efficiency and flexibility.