Current Affair 1:

Thermoelectric materials

 

Materials that can convert waste heat to electrical energy are called thermoelectric materials.

The thermoelectric effect refers to phenomena by which either a temperature difference creates an electric potential or an electric current creates a temperature difference. A typical thermoelectric material should have high electrical conductivity, low thermal conductivity and thus must maintain a temperature gradient.

Thermoelectric module (TEM) is constructed by two unique semiconductor materials most commonly Bismuth Telluride (Bi2Te3) (one n-type and  one p-type) used;  because, they must  have dissimilar electron densities.

 

 

 

The key phenomenon to generate thermoelectric effect is Seebeck effect, where electricity generates due to temperature differences.

The Seebeck Coefficient

1. In a thermoelectric material there are free electrons or holes which carry both charge and heat. To a first approximation, the electrons and holes in a thermoelectric semiconductor behave like a gas of charged particles.
2. If a normal (uncharged) gas is placed in a box within a temperature gradient, where one side is cold and the other is hot, the gas molecules at the hot end will move faster than those at the cold end (in addition to this thermodynamic difference between hot and cold, there can also be a scattering rate difference).
3. The faster hot molecules will diffuse further than the cold molecules and so there will be a net build-up of molecules (higher density) at the cold end.
4. The density gradient will drive the molecules to diffuse back to the hot end. In the steady state, the effect of the density gradient will exactly counteract the effect of the temperature gradient so there is no net flow of molecules.
5. If the molecules are charged, the build-up of charge at the cold end will also produce a repulsive electrostatic force (and therefore electric potential) to push the charges back to the hot end.

The electromotive force, measured as an electric potential produced by a temperature difference is known as the Seebeck effect and the proportionality constant is called the Seebeck coefficient.

Applications.

Thermoelectric (TE) materials have the capability of converting heat into electricity, which can improve fuel efficiency as well as provide a robust alternative energy supply in multiple applications by collecting wasted heat, and therefore assist in finding new energy solutions.

Thermoelectric materials can be included in novel applications as biothermal batteries, solid state thermoelectric cooling, optoelectronic devices, space, and automotive power generation.

Thermoelectric materials provide a sustainable energy alternative. “The ever-rising demand for energy is primarily addressed using earth’s renewable sources, out of which only a handful fraction of it is utilised and more than 65% wasted as form of heat. Thermoelectric devices thus are centric for global sustainability as they utilise the waste heat to generate electricity.

Current Affair 2:

Prison Statistics India (PSI) report 2021

 

The annual Prison Statistics India (PSI) report published by the National Crime Records Bureau (NCRB) provides comprehensive statistical information on various aspects of prison administration in India such as type of jails & occupancy, types of prisoners & demography, Indian & foreign prisoners, releases, transfers, movements, rehabilitation, and welfare of prisoners, etc

The report is based on the information produced by state prison departments. Recently, the NCRB released the report for 2021.

A total of (5,54,034) prisoners were confined as on 31st December, 2021 in various jails across the country. The number of Convicts, Undertrial inmates and Detenues were reported as 1,22,852, 4,27,165 and 3,470 respectively accounting for 22.2%, 77.1% and 0.6% respectively at the end of 2021.

Current Affair 3:

Asia-Pacific Institute for Broadcasting Development (AIBD)

 

NEWS:

The Asia-Pacific Institute for Broadcasting Development (AIBD) was established in August 1977 under the auspices of the United Nations Educational, Scientific and Cultural Organisation (UNESCO).

It is a unique regional inter-governmental organisation servicing countries of the United Nations Economic and Social Commission for Asia and the Pacific (UN-ESCAP) in the field of electronic media development. It is hosted by the Government of Malaysia and the secretariat is located in Kuala Lumpur.

The 26 full members of AIBD are the governments of the following countries:

Afghanistan, Bangladesh, Bhutan, Brunei, China, Cambodia, Fiji, France, India, Indonesia, Iran, Republic of Korea, Laos, Malaysia, Maldives, Micronesia, Myanmar, Nepal, Pakistan, Papua New Guinea, Philippines, Samoa, Singapore, Sri Lanka, Thailand, Vietnam.

 

Current Affair 4:

Market-Based Economic Dispatch (MBED) mechanism

 

First of all, it is related to Discoms.

What were the issues:

These constraints were analysed and highlighted in CERC’s Discussion Paper on Market Based Economic Dispatch published in December 2018, which proposed a re-design of the day-ahead scheduling and operation of the electricity markets in India.

It is in this backdrop that a Market Based Economic Dispatch (MBED) framework was proposed in a Discussion Paper released by the Central Electricity Regulatory Commission in December 2018, with substantial system cost savings, which would benefit end consumers.

The key advantages of MBED for key stakeholders can be highlighted as below:

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