Okay, to be quick and blunt, the stat should be called 'Heat Production' the way it is used, not Heat Efficiency.
Long version:
Efficiency is a ratio percentage of energy you get out from a process compared to what you put in.
It is expressed as Output divided by Input.
In example: If I get 47 units of energy out of a process I placed 100 units of energy into, it is expressed as 47 percent. Rephrasing this, it means that I get 47 units of energy that are usable or rather, used to do what I wanted to do, and the other 53 units of energy got converted to waste heat or vibrations and are thus trash. But efficiency is the percentage total of the USABLE energy, not the waste energy. That needs to be kept in mind.
Currently, the game expresses 'Heat Efficiency' as a stat, where in the value, usually hovering around '4' for modules I use, goes 'up' as it gets worse, and 'down' as it improves. Up indicating 'more heat' being produced, causing my ship to idle at a higher temperature; and down indicating 'less' heat being produced, allowing me to idle lower, and operated in high-temp states longer before overheat. This is flat out NOT Efficiency. It is PRODUCTION.
I have, multiple times, looked at this stat while doing loadout selections and engineering rolls, and have had to triple-check what I'm looking at because seeing the word 'efficiency' keeps crossing my mental wires. Usually, because when I watch a stat with the word 'efficiency' increase my brain goes 'Oh! MORE efficient! That's goo- wait. The color says its bad. WHY does the color say it's BAD?! Oh... That's not actually efficiency."
I suggest Frontier fixes this on their next pass of working on the UI. It's hardly a game breaking bug, but it's kind of teaching people an incorrect use for a word that should be WAY too common among us geeks to get wrong.
Long version:
Efficiency is a ratio percentage of energy you get out from a process compared to what you put in.
It is expressed as Output divided by Input.
In example: If I get 47 units of energy out of a process I placed 100 units of energy into, it is expressed as 47 percent. Rephrasing this, it means that I get 47 units of energy that are usable or rather, used to do what I wanted to do, and the other 53 units of energy got converted to waste heat or vibrations and are thus trash. But efficiency is the percentage total of the USABLE energy, not the waste energy. That needs to be kept in mind.
Currently, the game expresses 'Heat Efficiency' as a stat, where in the value, usually hovering around '4' for modules I use, goes 'up' as it gets worse, and 'down' as it improves. Up indicating 'more heat' being produced, causing my ship to idle at a higher temperature; and down indicating 'less' heat being produced, allowing me to idle lower, and operated in high-temp states longer before overheat. This is flat out NOT Efficiency. It is PRODUCTION.
I have, multiple times, looked at this stat while doing loadout selections and engineering rolls, and have had to triple-check what I'm looking at because seeing the word 'efficiency' keeps crossing my mental wires. Usually, because when I watch a stat with the word 'efficiency' increase my brain goes 'Oh! MORE efficient! That's goo- wait. The color says its bad. WHY does the color say it's BAD?! Oh... That's not actually efficiency."
I suggest Frontier fixes this on their next pass of working on the UI. It's hardly a game breaking bug, but it's kind of teaching people an incorrect use for a word that should be WAY too common among us geeks to get wrong.