This page details the temperature of all Mekanism and vanilla fluids, for use with the Geothermal Generator Unit. Note that these values are NOT used with the Heat Generator: all of these fluids have ambient temperature in that context.
For reference, the geothermal generator unit assumes that the environmental temperature is 300, and lava is 1000.
Thus, the best liquid to use is Uranium Oxide, generating around 1.9 MFE/s when fully submerged. Note that this is still much slower than the charging speed a properly upgraded Induction Matrix can provide if the MekaSuit is upgraded with Energy Units, but one may appreciate the free energy nonetheless.
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