The wellhead

The Basic Geothermal Wellhead is a Mekanism machine: it is built on Mekanism's own machine framework, so its interface, tabs, side configuration, auto-eject, Configurator modes, upgrades, redstone control, security and Jade display work as on Mekanism's machines.

The interface

• Gauges: water (left) and steam (right), and the energy bar.
• Status screen: production, steam rate and temperature, exhaustion, pressure (and the valve when it vents or cannot), drill state and progress, depth. Hover it for the details: tier max rate, control system, interference, water demand.
• Casing slots, target depth (arrows, Shift: ±10, mouse wheel), Start drilling and Emergency stop buttons, and the debris slots.
• Tabs: Mekanism's side configuration, transporter, upgrades, security and redstone control, plus the guide, heat and energy tabs.

Drilling

• The drill goes down one block at a time under the wellhead (40 ticks and 4,000 FE per block by default) and puts a Steel Well Casing in each hole. Every block it digs goes to the debris slots; take them out by hand or through an item output face.
• It stops at the target depth, or when it meets lava: the lava then heats the well (the drilling step of the guide counts as done).
• It waits, and says why, when it runs out of energy or casings, when the debris slots are full, or on a block it may not break (unbreakable, blacklisted, or protected by a claim: the drill acts with its owner's permissions).
• Caves: each air block crossed takes a casing and the energy of a drilled block, so the column stays continuous.
• Repairs: if a casing of the column is removed, the wellhead puts it back by itself (no button needed). While a casing is missing, the well produces no steam.

Heat and steam

The temperature of a well depends on the absolute Y of its bottom and on the dimension:

Dimension	Temperature	Production multiplier
Overworld	100 °C at Y 0 and above, rising linearly to 250 °C at Y −60	×1
Nether	180 °C at any depth	×0.6
End	no steam	—

Water boils above 100 °C: the temperature factor goes from 0 at 100 °C to 1 at 250 °C. Lava source blocks within 2 blocks of the bottom add 2 °C each, up to 50 °C.

Steam rate = max rate (400 mB/t for the Basic tier, ×2 with 8 Speed upgrades) × temperature factor × (1 − interference) × (1 − exhaustion), limited by the water available. The wellhead uses 1/0.95 mB of water per mB of steam (5 % blowdown). Boiling is passive: it needs no energy (energy only powers the drill and the control system).

Source	Steam	Best energy through a Mekanism turbine
Basic well at Y −60, alone and fresh	400 mB/t	1,600 FE/t
Basic well at Y −30	200 mB/t	800 FE/t
Basic well in the Nether	128 mB/t	512 FE/t
Smallest Mekanism fission reactor (0.1 mB/t burn)	2,000 mB/t	8,000 FE/t

Interference

Wells too close to each other share the heat. Each neighbour that produced in the last 3 seconds within 24 blocks costs 25 % × (1 − distance / 24): two wells side by side lose up to 25 % each, wells 24 blocks apart lose nothing. The total is capped at 75 % and recalculated every 5 seconds. Hover the status screen to see it.

Exhaustion

A column slowly exhausts under heavy load and recovers at rest. It is shown on the main screen, coloured like the damage of Mekanism's fission reactor (green, yellow, orange, dark red by quarters of the maximum).

• At full load, it grows by 1 % of the rate per Minecraft day, up to 15 % (about 15 days of continuous production, 7.5 with 8 Speed upgrades: the extra steam counts in the load).
• At rest, it recovers 5 % per day. A well under 83 % of its tier's rate never wears.
• It belongs to the column, not to the wellhead: breaking and replacing the wellhead does not reset it, and an unloaded well recovers while you are away.

Dismantling

Like Mekanism's machines, a broken wellhead keeps its energy, water, upgrades, casings, debris, settings, side configuration and redstone mode in the item; the steam is released. The casings stay in the ground: a new wellhead placed on the column takes it over without drilling again.