Exothermic Hearth

The Exothermic Hearth (ExH) is a ZPM tier multiblock for mass smelting dusts into ingots, crafting silicon boules, and heating up various materials. The ExH is a direct upgrade from the Electric Blast Furnace because it offers up to 512 parallels, supports multi-amp and laser energy hatches for serious overclocking, and has unlimited tier skips. That means it can run any recipe regardless of voltage tier as long as there is enough power and heat. The number of available parallels slowly increases up to 512 during activity and decreases back down to 256 while idle. Optionally, enable pyrotheum heating in the GUI of the controller to 6x the rate at which parallels are gained at the cost of 250-500 L/s of blazing pyrotheum. The ExH gains a 5% energy discount for every 900K over the recipe requirement and one perfect overclock for every 1,800K over the recipe requirement. The ExH only outperforms the Volcanus if it can take full advantage of its 512 parallels (4+ overclocks).

The ExH has two tiered components. The heating coils determine the maximum tier of recipes, the energy discount, and the number of perfect overclocks. The glass determines the maximum tier of the energy hatch. UMV tier glass removes all restrictions. Buses/hatches may replace any hearth casing anywhere on the structure, except for the muffler hatch which is limited to the center casing on the top layer of the structure. Multi-amp and laser energy hatches are supported, but the latter requires at least UV tier glass. Use the Multiblock Structure Hologram Projector to visualize/build the structure with subchannels "coil" and "glass" to specify the tier of those components.

Structure

• Controller: Front center, 4th layer
• 1800-1900 Hearth Casing
• 937 Heat Proof Machine Casing
• 864 Heating Coil (Tiered)
• 780 Thermal Containment Casing
• 428 Radiant Naquadah Alloy Casing
• 332 Any Tiered Glass (Tiered)
• 308 Black Plutonium Item Pipe Casing
• 280 Blast Smelter Heat Containment Coil
• 131 Tungstensteel Pipe Casing
• 56 Prismatic Naquadah Frame Box
• 1+ Energy Hatch: Any hearth casing
• 1 Maintenance Hatch: Any hearth casing
• 1 Muffler Hatch: Top center casing
• 1+ Input Bus/Hatch: Any hearth casing
• 1+ Output Bus/Hatch: Any hearth casing

Wallsharing

ExHs may wallshare each of their sides to save on casings and buses/hatches. However, that does not include any of the heating coils or glass.

The ExH is a direct upgrade from the Electric Blast Furnace because it offers up to 512 parallels, supports multi-amp and laser energy hatches for serious overclocking, and has unlimited tier skips. That means it can run any recipe regardless of voltage tier as long as there is enough power and heat. For example, a ZPM 256A laser energy hatch can run UIV recipes if the heat capacity is high enough. The glass tier only limits the voltage tier of the energy hatch, NOT the voltage tier of recipes.

The number of available parallels slowly increases up to 512 during activity and decreases back down to 256 while idle, as seen below. It takes 30 minutes of continuous activity to achieve the maximum 512 parallels but only 4 minutes and 16 seconds to lose it all. Optionally, enable pyrotheum heating in the GUI of the controller to 6x the rate at which parallels are gained at the cost of 250-500 L/s of blazing pyrotheum. The consumption rate scales linearly with the number of additional parallels, but it allows the ExH to achieve the maximum 512 parallels in just 5 minutes instead. Running out of blazing pyrotheum while pyrotheum heating is enabled causes the machine to immediately shutdown and void the current recipe.

• +0.711 parallels per 5 seconds while active (pyrotheum heating disabled), 30 minutes to max
• +4.267 parallels per 5 seconds while active (pyrotheum heating enabled), 5 minutes to max
• -1 parallel per second while idle, 4.26 minutes to min

Lastly, the ExH gains a 5% energy discount for every 900K over the recipe requirement and one perfect overclock for every 1,800K over the recipe requirement. There is also a +100K heat bonus for every voltage tier above MV with no upper limit, as seen in the following table.

The difference between the Volcanus and the ExH is not entirely obvious. The former has a very generous speed bonus but the latter has significantly more parallels. To help decide between the two, the following table compares the processing speed of raw neutronium dust with nitrogen gas for various overclocks. The ExH values are calculated with the maximum 512 parallels so its performance could be slightly worse in practice. The cells highlighted green indicate which multiblock is faster after normalizing for power.

From this information, it can be concluded that the Volcanus is the superior option for 0-3 overclocks and the ExH is the superior option for 4+ overclocks. This behavior is consistent across all recipes and heating coil tiers.

• The second half of the quote "Never one ..." is found in the Endothermic Fridge's tooltip.
• The Exothermic Hearth replaced the Mega Electric Blast Furnace in GTNH 2.9.