Dried Sea Peat

Taking wet soil from the sea bed to use as fuel seems so counter productive, but it is the best thing that ever happened for our society.

Dried sea peat is the main fuel used to create the steam which powers the whole world. Fire has of course been used throughout the ages, but with the invention of steam power, bigger and more advanced machines could be built. But this also meant there was a need for more fuel for the fires that create that steam.
For almost a decade, there was a great race to be the one who figured out the most efficient fuel for this. What has previously been used for fires was simply not feasible, as it took way too much material to create a small amount of power.
Then, sea peat was discovered. The sea bed in almost the whole Inner Sea is covered in a thick layer of soil consisting of old vegetation, compacted by the pressure from the water. This soil started to be extracted from the sea bed and experimented on until a recipe for excellent fuel was found.

Extraction

The extraction of Sea Peat is now a big industry in the towns around the Inner Sea. It is not easy to dig up soil from the sea bed, and the fatal accidents involved in the industry has been many.
However, it's a lucrative business since the peat pretty much drives the whole continent by now. And where there is money, there is going to be people.

Refining

While the peat can be burned as soon as it's dried up, this is usually not how it's used.
It is dried and combined with certain materials that ignite at high temperatures, before getting compressed into small and dense blocks. These blocks are then transported all over Tosormi to be sold as fuel for the steam production.