Continuing this short series on technology in Warhammer 40k from Rogue Trader, today we look at power generation.
The most obvious example is the first one, and one that Rogue Trader terms "conventional". This is the one that we're all familiar with. Burning fossil fuels to turn turbines to create electricity. And nuclear fission as well. But the word "conventional" does not terminate here for Rogue Trader. It also includes more "modern" (I use the term relatively) wind power, wave power, solar / photoelectric power, and even dung burning on some backward worlds.
The second one is also easy to guess at: Plasma. Given that plasma seems to be everywhere in Warhammer 40k (even weaponised!) its not hard to see why it is a source of power to this fictional era. The only problem with it is the immense magnetic fields (and indeed coils) that need to be generated to contain it. At the time of writing, its hardly efficient. And moreover, I'm not sure how plasma is a power source. Do they grab some by skimming stars and store it for later (to turn turbines and generate electricity)? Or something else. I think Rogue Trader is missing something here: plasma is not a source of power generation in and of itself (that's like saying electricity is a form of power generation - it isn't - it is the product). So I'm left wondering how it is actually generated. Rogue Trader is not specific on this point.
The last one is "crystal batteries". Yes - you read that correctly. But it is completely plausible. The underlying concept is that the crystals "decay" in to a more stable state and release energy doing so. This is just thermodynamics at play: a more energetic state of matter going down in to its lower (ground state?) configuration. It is then re-charged by exposure to sunlight (for instance) to get it back to its higher energy state. Plausible, but no efficient real world analogue at the moment. Great science fiction stuff based on sound thermodynamic principles!