Concept to extract heat energy from objects

In summary: This means that if your house is already heated, you're not going to be able to extract very much additional heat from the object.
  • #1
Dray1480
2
0
I was just thinking about absolute zero temprature roughly -250 c degress
Lets say an object has a room temprature of 20 degrees celcius
Doesnt it mean i has a lot of thermal emegy
So i used the equation

H= Cp x M x ΔT

H = Heat energy (in Joules)
m = mass (in kilograms)
delta T = change in temperature (in degrees Celsius)
Cp = Specific heat (in J/kg x degrees C)

If the material is glass with mass of 1 kg it would have 263550 joules of energy??

Im just a as student I am completely wrong just say so
 
Science news on Phys.org
  • #2
Q = M . C . dt (How do you get the triangle symbol) is how I write the equation, but they are the same thing.

You should work in kelvin really, but a change of 1 in either unit is equal so that's no big deal here.

Anyway, 0k is ~-273 degrees celsius.

What your equation says, is that it takes 263550 joules of energy to heat 1 kg of glass from 0k to 293k.

p.s I haven't actually checked your numbers, but assuming they work out.
 
Last edited:
  • #3
yes but the object is already heated to room temperature from its surroundings
 
  • #4
Yes, your object at room temperature has 263550 Joules more heat energy per kilogram than the same object at absolute 0. But so what? You titled this "Concept to extract heat energy from objects" and you said nothing about extracting the energy
 
  • #5
Dray1480 said:
yes but the object is already heated to room temperature from its surroundings

If what you're looking for is an efficient way to 'extract' that energy from an object, you simply need to place the object in a large temperature differential with good conductance.

It's basically a fridge.
 
  • #6
Dray1480 said:
If the material is glass with mass of 1 kg it would have 263550 joules of energy??

Im just a as student I am completely wrong just say so

Specific Heat capacity of glass is 840 Joules/kg/k so yes 1kg at room temperature 293K contains about 250,000 Joules.

It's not too hard to extract some of it. As lntz said you could put it in a fridge or use another type of heat pump.

Heat pumps for houses work by extracting heat from the outside air or ground and moving it indoors. They can even operate when the outside temperature is below freezing. The problem is that even the best heat pumps need some energy to run. The COP (Coefficient of Performance) for a typical heat pump for houses is typically in the range 2 to 6. In other words they use 1 unit of energy to move between 2 and 6 units of energy from outside to inside.
 

1. How does the concept of extracting heat energy from objects work?

The concept involves utilizing a heat source, such as a hot object or environment, and using a heat transfer mechanism, such as a heat exchanger, to transfer the heat energy to a working fluid. The working fluid is then used to power a heat engine, which converts the heat energy into usable mechanical or electrical energy.

2. What types of objects can be used as a heat source for this concept?

Any object that has a higher temperature than its surroundings can be used as a heat source, such as a hot surface, a flame, or even the Earth's natural heat from geothermal sources. The key is to have a significant temperature difference for efficient heat transfer.

3. How is the heat energy converted into usable energy?

The heat energy is converted through a heat engine, which can be a traditional steam engine, a gas turbine, or even a thermoelectric generator. These engines use the heat energy to produce mechanical motion, which can then be converted into electrical energy.

4. Is this concept environmentally friendly?

It can be, depending on the heat source and the working fluid used. For example, if renewable sources of heat energy are used, such as solar or geothermal, and environmentally friendly working fluids, such as water, are utilized, then the concept can be considered environmentally friendly.

5. What are some real-world applications of this concept?

This concept has many practical applications, such as in geothermal power plants, waste heat recovery systems, and solar thermal power plants. It can also be used in everyday devices, such as solar water heaters and air conditioners, to harness heat energy for domestic use.

Similar threads

  • Thermodynamics
Replies
28
Views
1K
Replies
6
Views
1K
  • Thermodynamics
Replies
3
Views
950
  • Thermodynamics
Replies
26
Views
1K
Replies
4
Views
4K
  • Thermodynamics
Replies
7
Views
2K
  • Thermodynamics
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
889
  • Introductory Physics Homework Help
Replies
13
Views
2K
Replies
18
Views
1K
Back
Top