zt [TNT](zeptotonne)

Zeptotonne (zt) is a unit used to describe a tiny amount of energy, often used within the context of nuclear energy, explosions or other natural events involving the release of energy.

The term "zepto" refers to a prefix indicating a factor of 10^-21, meaning a zeptotonne is equal to one trillionth of a billionth (10^-21) of a tonne. The unit of energy associated with the zeptotonne is typically expressed in tons of TNT, where TNT (trinitrotoluene) is a conventional unit of energy for describing large-scale events like explosions.

So, to understand what is a zeptotonne (zt) of TNT, it's an extremely minuscule unit, equal to 10^-21 tonnes of TNT, representing a very small amount of energy typically demonstrated in nuclear reactions, explosions, or other high-energy events.

Zt [TNT](zettatonne)

Unit Zt or zettatonne of TNT is a unit of energy used in the field of energy to express very large amounts of energy. It is based on the energy released by the explosion of one zettatonne (10^21 tonnes) of trinitrotoluene (TNT).

TNT is a commonly used reference explosive, and its energy content has been standardized for comparing the energy released by different events, such as earthquakes, nuclear explosions, or asteroid impacts. One tonne of TNT is equivalent to approximately 4.184 gigajoules of energy. So, one zettatonne of TNT is equivalent to 4.184 * 10^21 gigajoules of energy. This unit is helpful in expressing and comparing energy values involving large-scale events that release tremendous amounts of energy.

MDth [EC](thousand decatherms)

A thousand decatherms (MDth or MDT) is a unit of energy that is commonly used in the field of natural gas, utilities and energy trading. A decatherm (Dth) is equal to 10 therms or 1,000,000 British Thermal Units (BTUs).

As the name suggests, a thousand decatherms (MDth) equals 1,000 decatherms, i.e., 1,000 x 10 therms = 10,000 therms. In terms of BTUs, one MDth is equal to 1,000 x 1,000,000 BTUs = 1,000,000,000 BTUs.

This unit is often used to measure the energy content of natural gas or other fuels, as well as in measuring the energy consumption of large commercial or industrial users. Additionally, it is also used in pricing, billing, and trading activities related to natural gas and energy markets.