Electricity, Heat, and Energy - Quality & Conversion

In summary, electricity and heat are both forms of energy, but their quality differs due to factors such as entropy and temperature. While it is possible to convert one form into the other, it is difficult and some energy may be lost in the process. The quality of a form of energy can be measured by its corresponding unit, such as voltage for electricity and temperature for heat.
  • #1
haiha
136
1
My idea is : electricity can be transferred 100% into heat. Mechanical energy can be as well. But heat can not be transferred completely into electricity or mechanical energy. From that point of view, I think that electricity and heat and... are all some forms of energy, but the quality of each kind is different?
 
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  • #2
They CAN be transformed back to electricity, but it is very difficult to do it, the "quality" have sunk, but the energy is still there and have not lessened!

We think the only way to create matter from heat is to make the heated atoms send out their energy at a such high frequenzy that if two photons collided they would create a tiny amount of anitmatter and matter. This is of course much more difficult than making the matter send out photons.
 
  • #3
haiha said:
My idea is : electricity can be transferred 100% into heat. Mechanical energy can be as well. But heat can not be transferred completely into electricity or mechanical energy. From that point of view, I think that electricity and heat and... are all some forms of energy, but the quality of each kind is different?

Jarle said:
They CAN be transformed back to electricity, but it is very difficult to do it, the "quality" have sunk, but the energy is still there and have not lessened!

We think the only way to create matter from heat is to make the heated atoms send out their energy at a such high frequenzy that if two photons collided they would create a tiny amount of anitmatter and matter. This is of course much more difficult than making the matter send out photons.

Yikes!

To the original question: Just to make sure you don't get led down the wrong way, there is another consideration here that you missed - entropy.

You can't just account for energy content when doing conversion from one form to another. You also have to consider the entropy at every stage of the conversion. Converting one form that has a higher degree of entropy into something that has a lower degree of entropy is difficult (i.e. you won't get ALL of it back), or will require other forms of energy (such as work done) to facilitate the conversion.

So yes, while energy is energy, the forms of energy have other factors that have to be considered when converting from one to the other.

Zz.
 
  • #4
ZapperZ said:
Yikes!

To the original question: Just to make sure you don't get led down the wrong way, there is another consideration here that you missed - entropy.

You can't just account for energy content when doing conversion from one form to another. You also have to consider the entropy at every stage of the conversion. Converting one form that has a higher degree of entropy into something that has a lower degree of entropy is difficult (i.e. you won't get ALL of it back), or will require other forms of energy (such as work done) to facilitate the conversion.

So yes, while energy is energy, the forms of energy have other factors that have to be considered when converting from one to the other.

Zz.

I agree with you at some point. But people still use different units to measure those forms of energy: calorie, joule, watt and Newton metre and the conversion fators from one to another (and vice versa) is fixed. Should there be certain equation describing the 'difficulty' of converting from high entropy into low entropy form of energy (let say from heat into electricity)?
 
  • #5
The measure of the quality of an electric current is voltage, and the measure of the quality of a thermodynamic substance is temperature. ie, the higher the voltage, the higher the temperature of the heat which could be produced from it.
 
  • #6
haiha said:
I agree with you at some point. But people still use different units to measure those forms of energy: calorie, joule, watt and Newton metre and the conversion fators from one to another (and vice versa) is fixed. Should there be certain equation describing the 'difficulty' of converting from high entropy into low entropy form of energy (let say from heat into electricity)?

Yes, there should be. And with regard to photon distributions, there is. The quality of a photon is measured by its frequency, and the quality of a thermodynamic substance by its temperature. There's a simple formula which allows one to convert between photon frequency and photon 'temperature'. For instance, the radiation we receive from the Sun is very nearly the same as the radiation which would be emitted by a black body at 6000 K. Hence, we can say that visible light (which is at the peak of the photon distribution emitted by the Sun) has a temperature of around 6000 K. This is what makes life on Earth possible. We receive 6000 K energy from the Sun and radiate ~290 K energy back into outer space.
 

1. What is the difference between electricity and heat?

Electricity and heat are both forms of energy, but they differ in how they are produced and used. Electricity is a flow of charged particles, typically electrons, while heat is a measure of the total kinetic energy of molecules in a substance. In other words, electricity is the movement of particles, while heat is the energy of those particles.

2. How is energy quality and conversion related to electricity and heat?

Energy quality refers to the ability of energy to perform work or produce useful output. The conversion of one form of energy to another, such as electricity to heat, can affect the quality of the energy. For example, converting electricity to heat in a power plant results in a loss of energy quality due to inefficiencies in the conversion process.

3. What are some ways that electricity can be generated?

Electricity can be generated through various methods, including burning fossil fuels, harnessing the power of moving water (hydroelectricity), using nuclear reactions, and capturing renewable sources such as wind and solar energy. Each method has its own advantages and drawbacks in terms of cost, environmental impact, and efficiency.

4. How is energy converted from one form to another?

Energy conversion is the process of changing energy from one form to another. This can be done through mechanical, thermal, chemical, or electrical means. For example, an electric heater converts electrical energy into heat energy, while a car engine converts chemical energy from fuel into mechanical energy to power the vehicle.

5. What are some examples of energy efficiency and how can it be improved?

Energy efficiency refers to the amount of useful energy output compared to the total energy input. Some examples of energy efficiency include using energy-efficient appliances, improving insulation in buildings to reduce heating and cooling needs, and using alternative transportation methods such as biking or public transportation. Energy efficiency can be improved through technological advancements, behavioral changes, and government regulations and incentives.

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