What is the main advantage of non-conventional energy sources compared to conventional ones?
Get proficient with the Power Engineering concepts with detailed lessons on the topic Renewable and Non-Renewable Energy among many others.
The correct answer is They are more sustainable and environmentally friendly.
There are basically two sources of energy:
Renewable resources or Non-Conventional
Non-Renewable resources or Conventional
The resources can renew themselves or can be used again and again.
The sources cannot be replaced or reused once they are destroyed.
Renewable resources are replenished naturally and over relatively short periods of time .
It is present in unlimited quantity
These are limited resources and consume millions of years to make.
So these are used limitedly.
It has low carbon emission and is hence is environment friendly.
These are not environmentally friendly because the amount of carbon emission is high .
The cost is low.
The cost of these resources is high.
A large land area is required for the installation of these plants.
Less land requirement of installation of these plants.
They require high maintenance costs.
They require low maintenance costs.
Example: soil, water bodies, sun (solar energy), wind, tidal energy, atomic energy, geothermal, forest, mountains, biogas, wildlife, atmospheric resources.
Example: coal, oil, nuclear energy, petroleum, natural gas, LPG, batteries, shale gas, soil and phosphate are some examples.
Advantage of non-conventional sources of energy
Which material is commonly used in high-temperature solar thermal energy storage systems for its ability to store a large amount of heat?
Concept:
High-temperature solar thermal energy storage systems require materials that can store and release large amounts of heat efficiently. One of the most commonly used materials for this purpose is molten salts.
Molten salts are chosen for their excellent thermal properties. They have a high specific heat capacity, which means they can store a significant amount of thermal energy per unit mass. Additionally, they have a relatively high thermal conductivity, which allows for efficient heat transfer. These properties make molten salts ideal for use in concentrated solar power (CSP) plants, where they are used to store heat collected from solar radiation during the day and release it to generate electricity when sunlight is not available.
Other materials like silicon, lithium-ion batteries, and water are also used in energy storage systems, but they have limitations when it comes to high-temperature applications. Silicon is typically used in photovoltaic cells, lithium-ion batteries are used for electrical energy storage, and water is commonly used in low-temperature thermal storage systems.
Explanation:
Let's analyze each of the options provided:
Option 1: Silicon
Silicon is primarily used in photovoltaic (PV) cells for converting sunlight into electricity. While it has excellent properties for electronic applications, it is not commonly used for high-temperature thermal energy storage due to its lower thermal capacity and challenges in handling at high temperatures.
Option 2: Molten salts
Molten salts, such as a mixture of sodium nitrate and potassium nitrate, are widely used in high-temperature thermal energy storage systems. These salts can operate at temperatures ranging from 300°C to over 500°C, making them suitable for CSP plants. They have a high specific heat capacity and thermal conductivity, allowing them to store and transfer large amounts of heat efficiently.
Option 3: Lithium-ion batteries
Lithium-ion batteries are commonly used for electrical energy storage in applications such as portable electronics, electric vehicles, and grid storage. However, they are not suitable for high-temperature thermal energy storage due to their limited thermal stability and potential safety risks at elevated temperatures.
Option 4: Water
Water is a common medium for low-temperature thermal energy storage, such as in solar water heating systems. However, its use is limited to temperatures below 100°C due to its boiling point at atmospheric pressure. For high-temperature applications, water is not suitable due to phase change and pressure handling requirements.
Conclusion:
Considering the thermal properties and suitability for high-temperature applications, molten salts are the most commonly used material in high-temperature solar thermal energy storage systems. They can efficiently store and release large amounts of heat, making them ideal for use in CSP plants. Therefore, the correct answer is:
The correct answer is option 2: Molten salts