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Codex Energy Geothermal Exchanger
The Geothermal Heat Exchanger draws heat from the ground and hands it to the heat consumers next to it. It makes no energy itself, needs no fuel, no water and no power: place it deep enough, put a consumer beside it, and heat flows. It is a tier I block.
- The ground is warmer the deeper you go. In the Overworld the exchanger offers 4 HU/t for every block it stands below height 63, up to 500 HU/t (see the table below).
- Other dimensions: in the Nether it offers 600 HU/t at every height; in the End nothing.
- It hands the heat to its six neighbours that take heat, one after the other, until the heat of the tick is used up. Heat nobody takes is not lost from the ground, it simply stays there.
- The region gets tired. The world is divided into regions of 128 × 128 blocks. Every region gives 500,000,000 HU at full strength. Beyond that it gives less and less: the share 1 / (1 + taken / 500,000,000). After one budget it gives half, after three budgets a quarter, but never nothing. Only heat that a consumer really took counts, and every exchanger in the region draws from the same budget.
Note
How long a region lasts One exchanger delivering 500 HU/t without a break uses one budget in about 14 hours of play. Several exchangers in the same region tire it out faster; one in the next region starts fresh.
| Height of the exchanger | Heat on offer (HU/t) |
|---|---|
| 63 and above | 0 |
| 32 | 124 |
| 0 | 252 |
| −40 | 412 |
| −62 and below | 500 |
| Nether, any height | 600 |
| End | 0 |
The exchanger gives heat to every neighbour that accepts heat, on all six sides:
- a Heat Port of a plant whose outer face touches the exchanger: an Industrial Boiler (it boils water into steam with it), a Foundry, a Chemical Plant and other plants with Heat Ports;
- a Stirling Generator, which turns it into electricity;
- heat consumers of other mods that use QNet's heat interface.
Each consumer takes only what it can use: a Stirling Generator up to 240 HU/t, a boiler up to 40 HU/t per Heat Exchanger Tube. More on heat and Heat Ports: Process heat.
- Height: the height of the exchanger.
- Heat from below: what the ground offers at this height, before the region's share.
- Region still gives: the share of the region, 100 % in an untouched region.
- Heat: the heat on offer now (ground heat times the region's share).
- Heat taken from the region (HU): what all consumers of this region have taken so far.
- The diagram shows the heat that went to the neighbours in the last tick.
The exchanger has no buttons and no status line.
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| Bucket | Blast Furnace | Bucket | → Geothermal Heat Exchanger |
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Magma Block | |
The exchanger keeps nothing of its own: what the region has given is stored with the world, so breaking and placing it again changes nothing.
The bore pump's rod and flywheel move while heat flows, faster with more heat. Its vents glow and give light by the heat it delivers, in three stages; without a consumer it stays dark and still.
Tip
Deep and in the Nether Dig down to the bottom of the Overworld for the full 500 HU/t, or go to the Nether, where 600 HU/t come at any height. Two Stirling Generators (three in the Nether) or one boiler with enough tubes use all of it.
Warning
Heat into a boiler keeps coming A boiler stops burning its own fuel at its setpoint, but heat from a Heat Port keeps coming. If its steam cannot leave, the boiler goes into overpressure; build Safety Valves into it (see Industrial Boiler).