How Much Heat is Supplied and Exhausted in a Gas-Fired Cogeneration Power Plant?

In summary, a gas-fired power plant operating between temperatures of 900 K and 300 K generates 30 MW of electrical power and uses waste heat for space heating. The Carnot Efficiency for this plant is 66.7%. For question 1, the amount of heat that must be supplied is 0.50 times the work output. For question 2, the amount of heat exhausted to the cold reservoir is 0.50 times the work output minus the heat supplied. The Carnot efficiency does not need to be included in the calculations.
  • #1
pcoppin
2
0

Homework Statement



A small gas-fired power plant which operates between temperatures of 900 K and 300 K
generates 30 MW of electrical power. Some of the waste heat from the generation process is used to heat water for space heating.
The Carnot Efficiency for this plant is 66.7%


Homework Equations



Question 1. If the actual efficiency is 50% find the amount of heat which must be supplied to the power plant?

Question 2. Calculate the amount of heat exhausted to the cold reservoir.



The Attempt at a Solution



For both questions, I am not sure which variables to use and if I need to take into account - do I need to include the carnot efficiency in the calculations?
 
Last edited:
Physics news on Phys.org
  • #2
If I use q_h = heat supplied, q_c = heat rejected and W = work output then, For question 1: q_h = 0.50W For question 2: q_c = 0.50W - q_h
 

FAQ: How Much Heat is Supplied and Exhausted in a Gas-Fired Cogeneration Power Plant?

What is a gas fired cogeneration power plant?

A gas fired cogeneration power plant is a type of power plant that generates electricity by burning natural gas. It also captures and uses the waste heat produced during the electricity generation process, making it more efficient than traditional power plants.

How does a gas fired cogeneration power plant work?

In a gas fired cogeneration power plant, natural gas is burned in a combustion turbine to produce electricity. The waste heat from the combustion process is then used to generate steam, which drives a steam turbine to produce even more electricity. The plant also captures and uses any excess heat for heating or cooling buildings.

What are the benefits of a gas fired cogeneration power plant?

Gas fired cogeneration power plants are more efficient than traditional power plants, as they use both the electricity and waste heat produced. This results in lower fuel consumption and reduced greenhouse gas emissions. They also have the ability to provide reliable and continuous power, making them a valuable source of energy.

What are the potential drawbacks of a gas fired cogeneration power plant?

One potential drawback of a gas fired cogeneration power plant is the initial cost of installation, which can be higher than traditional power plants. Another potential issue is the reliance on a single fuel source, which can lead to price fluctuations. Additionally, the waste heat produced may not always be able to be utilized effectively, leading to lower overall efficiency.

What are some examples of gas fired cogeneration power plants?

There are many gas fired cogeneration power plants around the world, including the Eneco Energiecentrale Rotterdam in the Netherlands, the Lodi Energy Center in California, and the Queen Elizabeth Hospital Energy Centre in the United Kingdom. These plants vary in size and capacity, but all use natural gas as their primary fuel source to generate electricity and heat for surrounding buildings.

Similar threads

Max power plant output w/o killing river smelt?
Replies
10
Views
3K
Pressure change at the inlet of a steam turbine in a small electric power plant
Replies
4
Views
4K
Questions on operating a nuclear power plant on the Moon or Mars
Replies
13
Views
1K
Chemistry Work done by heat engine that uses exhaust from heat pump
Replies
1
Views
536
Calculating Natural Gas Requirements for a 1000MW Power Plant
Replies
2
Views
5K
Seawater power plant efficiency
Replies
4
Views
2K
Power plant generator improvement
Replies
20
Views
3K
As much steam as possible from engine exhaust gas + warm water?
Replies
25
Views
3K
B Question regarding Heat Transfer in Carnot Engine
Replies
1
Views
1K
Power & Engine efficiency - Using heat (kelvin)
Replies
1
Views
4K

Hot Threads

Recent Insights

Back
Top