What is a bottoming cycle?
A bottoming cycle is a thermodynamic cycle which. generates electricity from waste heat, as opposed to a topping cycle, in which. waste heat from electricity generation is rejected to the environment (cooling wa- ter, atmosphere), or used for heating purposes in industry or for district heating. purposes (cogeneration) …
Which one is produced first in bottoming cycle?
In a bottoming cycle, the primary fuel produces high temperature thermal energy and the heat rejected from the process is used to generate power through a recovery boiler and a turbine generator.
What do you mean by Topping Cycle & bottoming cycle?
In a topping cycle, the fuel supplied is used to first produce power and then thermal energy, which is the by-product of the cycle and is used to satisfy process heat or other thermal requirements. Topping cycle cogeneration is widely used and is the most popular method of cogeneration.
What is topping and bottoming cycle in cogeneration?
There are two main kinds of cogeneration cycle: a topping cycle and a bottoming cycle. The topping cycle really is the only economic cycle of the two. The main heat source generates high-enthalpy steam and electricity. If the steam is taken from the turbine exhaust, this is called a back pressure turbine.
Why is Brayton pressure constant?
Ideal Brayton cycle: isentropic process – ambient air is drawn into the compressor, where it is pressurized. isobaric process – the compressed air then runs through a combustion chamber, where fuel is burned, heating that air—a constant-pressure process, since the chamber is open to flow in and out.
What is CHP cycle?
In a bottoming cycle CHP system, also referred to as “waste heat to power,” fuel is first used to provide thermal input to a furnace or other industrial process and heat rejected from the furnace or process is then used for electricity production.
What is Rankine cycle efficiency?
In modern nuclear power plants, which operate the Rankine cycle, the overall thermal efficiency is about one-third (33%), so 3000 MWth of thermal power from the fission reaction is needed to generate 1000 MWe of electrical power.
Which cycle is used in steam power plant?
steam Rankine cycle
The steam Rankine cycle is one of the highest utilized types of thermodynamic cycles for electricity production in the world [1]. The steam power stations run on Rankine cycles using steam as a working fluid. The simple ideal Rankine cycle is in fact the most basic vapor power cycle.
Why the mercury cycle is topping cycle in binary Vapour cycle?
There are two cycles in this- mercury cycle and steam cycle. Calculation of the efficiency: The mercury leaves the condenser as saturated liquid and steam leaves as the saturated vapour. The mercury cycle 1-2- 2′-3-4-1 is named as topping cycle and steam cycle 5-6-6′-7-8-5 as bottoming cycle.
What is the principle of cogeneration?
19.3 Principle of cogeneration Cogeneration or combined heat and power (CHP) is defined as the sequential generation of two different forms of useful energy from a single primary energy source, typically mechanical energy and thermal energy.
Why cogeneration is a way of energy conservation?
Cogeneration is a method of energy conservation that involves the production of two types of energy at a single power plant. Energy efficiency or conservation refers to the process of reducing the amount of energy that’s wasted, and some scientists consider it an energy source of its own.
What is the efficiency of Rankine cycle?
Which is not efficient in the bottoming cycle?
Gas turbine power plant with waste heat recovery and a steam generator (boiler). Combined-cycle gas turbine plus steam turbine plant (steam turbine can be back pressure or condensing type). The bottoming cycle is not very efficient.
How is air bottoming cycle used in combined cycle power plant?
Air Bottoming Cycle (ABC) can replace the heat recovery steam generator and the steam turbine of the conventionalcombined cycle plant. The exhaust energy of the topping gas turbine of existing combine cycle is sent to gas-air heat exchange, which heats the air in the secondary gas turbine cycle.
How did the topping cycle get its name?
Topping Cycle. A topping cycle takes its name from the fact that it the electricity generating system that is the primary, or top, user of an energy source. From: Combined Heat and Power, 2018. Related terms: Supercritical; Gas Turbines; Steam Turbines; Turbines; Bottoming Cycle; Organic Rankine Cycle; Heat Recovery
What are the benefits of the topping cycle?
The British Coal Topping Cycle. The expected benefits of the Topping Cycle are a 20% reduction in electricity generating costs compared to conventional power generation systems, a corresponding reduction in CO 2 emissions, low capital costs and low emissions of SO 2 and NO X.
