What is Energy transfer?

The flow of energy from one region to another region is referred to as energy transfer. Since energy is quantitative; it must be transferred to a body or a material to work or to heat the system.

Types of Energy

The most common form of energy includes,

• Potential energy: The energy owned by the body in the immovable position.
• Kinetic energy: It is the mass-energy gained by its motion and also by the motion of electrons, waves, substances, molecules.

Various forms of energy

• Chemical energy: It is reserved in the bonds of molecules and atoms. Some examples of chemical energy are batteries, biomass, and natural gas.
• Mechanical energy: It is reserved in the object with the help of tension. Examples are compressed strings and stretched bands.
• Nuclear energy: This energy is present in the nucleus of the atom. It is the energy that holds the atom together.
• Thermal energy: It is also referred to as heat energy. Due to the flow of atoms and molecules, there is a rise in heat energy which is known as thermal energy. The heat energy increases when the particle moves faster in the system.
• Radiant energy: It is simply made of electromagnetic radiation (EMR)). It includes X-rays, UV rays, visible light, and gamma rays. They travel through transverse waves. Sunlight is the lively example for radiant energy.

Types of Energy transfer

We know that energy can neither be created, nor be destroyed.  Energy can be transferred from one point to another point or it may be transformed from one state to another state. It takes place in many ways i.e., by doing work or by heat transfer.

By doing work

Whenever work takes place, there occurs a flow of energy from one object to another. For doing work, a certain person or an object needs particular energy to exert some force on another object to some extent. Afterwards, when the work is done, energy gets transmitted from person to object. Hence, the kinetic energy of the object is changed and thereby, position of the object is also changed.

For example, imagine a person pushing a cart, he exerts some force on a cart that is loaded with weight that is initially at rest. When the force is exerted on the cart, the cart moves to some extent. Hence, the kinetic energy of the cart increases. Can you predict from where the cart gets its kinetic energy? The person who pushes the cart transfers a certain amount of chemical energy to the cart, which makes the cart move. Henceforth, the person’s stored chemical energy is converted into the cart as kinetic energy.

Heat transfer

When molecules at different temperatures begin to flow from high to low-temperature regions heat energy is transferred. The flow of heat takes place in three different ways. They are:                                                

• Conduction: When two molecules hit each other directly, there occurs a fall of energy. For example, in the pool game, when a ball hits the other one the ball moves. Conduction occurs in solid, liquid, and gases, but mostly occurs when the molecules  are tightly packed together.
• Convection: When the heat flows through the liquid (water) or gas flow from a warm place to a cold place, it transfers some heat also.
• Radiation: Here, energy transfer takes place through electromagnetic waves. It doesn’t require any object or matter to transfer heat. When you stand in the sunlight, you are warmed by the sun rays that reach the earth. Light bulbs, irons, toasters also transfer heat via radiation.

Energy transfer through gas

So far, we have discussed energy transfer that takes place through solids and liquids, now we are getting into energy transfer through the gas. On land, the natural gas is carried through large pipelines, or by ship on the water. Mostly natural gas is transported in large pipelines. Hence, the infrastructure includes a large number of pipelines for quick and faster delivery of the gas. This complex structure involves three different types of pipeline systems along the transportation line, they are:

• Gathering pipeline system: This system consists of small pipelines comprising low pressure. It helps to carry the raw form of natural gas from the source to the production plant.
• Intrastate/interstate pipeline system: Both the pipeline systems are the same and their goal is to transport the gas from the production plant to the core of its consumption unit.
• Distribution pipeline system: It helps to distribute the processed gas to needed consumers.

The steps involved to extract the natural gas are as follows:  A single-stage separator separates the liquid from the gas which are present in the natural gas. The separated liquid then enters into the condensate separator to remove the contaminants and it is directly sent to the storage unit. To prevent the condensation due to water vapor that is formed in the pipelines, dehydration should be done. Contaminants such as $H_{2}S, C{O}_2, N_2, O_2$, helium can be removed when it is passed through the container containing amine solution. Nitrogen Rejection Unit (NRU) helps to extract the nitrogen from the contaminants through the molecular sieve beds. De-methanization or methane separation happens through cryogenic processing techniques and absorption techniques.

Liquified Natural gas (LNG)

If the transfer of natural gas is not possible by pipelines, then it will be liquified and transported via ship. This liquified state of the gas is known as liquified natural gas (LNG). When the natural gas is changed to liquified form, it takes a small volume and makes the shipment and storage easier. The infrastructure of LNG includes gas pipelines heading to the sea, a gas liquefication plant, and storage room for gas storage, and a terminal for shipment.

 After the shipment, the liquified natural gas is again transformed into natural gas.

Energy transfer partners

The production and process of natural gas transport take place on a large scale in Energy transfer Company LP. The company’s infrastructure is finely planned with a large natural gas unit and propane gasoline transport unit. In 1995, Ray Davis and Kelcy Warren started the company organized under the Delaware state laws with the headquarters as Dallas, Texas. This company joined its hand with Regency Energy Partners, bought midstream assets from Castleton commodities international for 2 Billion dollars in 2011.

Sunoco LP is an American master limited partnership organized under Delaware state laws, with their headquarters is at Dallas, Texas. It is a wholesale distributor of motor fuels that channelizes 7300 gas stations and almost all are administered by third parties. Their tie-up is controlled by Energy Transfers LP.

This company has a 32.4% limited tie-up with Sunoco Logistic partners and works with a divided portfolio of crude oil and refined products pipelines, terminating crude oil acquisitions and marketing assets.

The energy transfers also have 36.4% interest in Dakota Access LLC. It is responsible for the Dakota Access Pipeline or Bakken Pipeline.

The company has a huge pipeline for natural gas transportation of around 21 billion ft³ capacity and it has three storage facilities in Texas and 12200 miles of interstate gas pipelines and it has a transportation capacity of around 10.3 billion ft³/day.

Context and Applications

This topic is an important subject for both postgraduate and undergraduate courses, Bachelor and Masters in Science (physics.)

Practice Problems

Question 1: Guess the type of transfer that takes place below.

Heat energy transforms through liquid or gas is _____.

1.  Conduction 
2.  Convection
3.  Radiation 
4.  Oxidation

Answer: The correct option is b.

Explanation: The process by which the heat is transferred through water or air is convection. The heat energy is transferred through the liquid when the liquid or air flows from high temperature to low-temperature region and. While boiling the water in the pan, the cold water at the base heats and rises up. As the hot water rises, the cold water rushes down, to replace the hot water. This process takes place in a continuous circular manner.

Question 2: What does LNG stand for?

1. Liquified natural gas
2. Liquified nitrogen gas
3. Liquid nitrogen gas
4. Low natural gas

Answer: The correct option is a.

Explanation: The liquified state of the gas is called liquified natural gas (LNG).

Question 3: Energy is stored in atoms and bonds is called ____.

1. Thermal energy
2. Chemical energy
3. Nuclear energy
4. Mechanical energy

Answer: The correct option is b.

Explanation: The energy stored in the bonds and atoms is called chemical energy. It creates during the chemical reaction often in the form of heat. Examples are batteries, natural gas.

Question 4: The law of conservation of energy states______.

1. Energy can neither be created nor be destroyed
2. Energy can be created and destroyed
3. Energy cannot be created but can be destroyed.
4. None of these

Answer: The correct option is a.

Explanation: The law of conservation of energy states that energy can neither be created nor be destroyed, but it can be converted from one form to another.

Question 5: Name the pipeline which is used to transport gas from production plant to unit?

1. Gathering pipeline system
2. Distribution pipeline system
3. Intrastate/interstate pipeline system
4. None of these

Answer: The correct option is c.

Explanation: The pipeline which is used to transport gas from the production plant to the consumption unit is called an intrastate/interstate pipeline system.