diff --git a/README.md b/README.md
index 3b56634..0d7c732 100644
--- a/README.md
+++ b/README.md
@@ -144,6 +144,8 @@ total 32x Blast Furnaces, 4x2x4:
 ### Power Upgrade
 - +1 stack geothermal generators
 
+For details see [here](./calculations/geothermial_power.md).
+
 ### Plate-Bender setups:
 - 4x Iron plates, limit 2048
 - 2x Steel plates, limit 512
@@ -200,6 +202,11 @@ In 3x3 Chunk Fläche:
 
 ## Mid Game
 
+### Lava centrifuges
+At some point, start building centrifuges for lava producing copper and tin! Start with 32 or 64, then expand later.
+
+For more details [see here](./material_calculations/lava_calcs.md).
+
 ### Frame Quarry
 - 144 Support Frames (+32-64 later)
 - 120 Redstone Tube Frames
diff --git a/material_calculations/chrome_calcs.md b/calculations/chrome_calcs.md
similarity index 100%
rename from material_calculations/chrome_calcs.md
rename to calculations/chrome_calcs.md
diff --git a/calculations/geothermial_power.md b/calculations/geothermial_power.md
new file mode 100644
index 0000000..ead6e25
--- /dev/null
+++ b/calculations/geothermial_power.md
@@ -0,0 +1,31 @@
+# Power from lava in geothermial generators
+
+## Production 
+
+1 Geothermal Generator produces 20EU/t with lava and consumes 1 bucket of lava in 50s at max capacity. 32 Generators produce 640EU/t and 64 produce 1280EU/t.
+
+## Cost
+
+1 Geothermal Generator needs:
+- 10 refined iron
+- 6 tin
+- 4 glass
+- 2 redstone
+- 1/2 copper
+- 1 rubber
+
+32 need:
+- 5 stacks of iron (320)
+- 3 stacks of tin (192)
+- 2 stacks of glass (128)
+- 1 stack of redstone (64)
+- 18 copper -> 36x cable
+- 36 rubber -> 36x cable
+
+64 need:
+- 10 stacks of iron (640)
+- 6 stacks of tin (384)
+- 4 stacks of glass (256)
+- 2 stacks of redstone (128)
+- 33 copper -> 66x cable
+- 66 rubber -> 66x cable
diff --git a/material_calculations/iridium_calcs.md b/calculations/iridium_calcs.md
similarity index 100%
rename from material_calculations/iridium_calcs.md
rename to calculations/iridium_calcs.md
diff --git a/calculations/lava_calcs.md b/calculations/lava_calcs.md
new file mode 100644
index 0000000..358a67b
--- /dev/null
+++ b/calculations/lava_calcs.md
@@ -0,0 +1,29 @@
+# Lava centrifuging to Copper and Tin
+
+## Production
+
+One centrifuge converts 16 Lava buckets to 4 Copper Ingots, 2 Tin Ingots, 1 Electrum Ingot and 2 tiny piles of Tungsten in 500 seconds, using 5EU/t.
+
+| Item | 1 centrifuge | 64 | 128 | 192 | 256 | 6 stacks | 8 stacks | 10 stacks |
+|------|--------------|----|-----|-----|-----|----------|----------|-----------|
+| Lava per Minute | 1.92 | 123 | 246 | 369 | 492 | 737 | 983 | 1229 |
+| Copper per Minute | 0.48 | 31 | 61 | 92 | 123 | 184 | 246 | 307 |
+| Tin per Minute | 0.24 | 15 | 31 | 46 | 61 | 92 | 123 | 154 |
+| Electrum per Minute | 0.12 | 7.7 | 15 | 23 | 31 | 46 | 61 | 77 |
+| EU/t | 5 | 320 | 640 | 960 | 1280 | 1920 | 2560 | 3200 |
+
+Roughly one pair of boilers needed per stack of centrifuges, or 16 Geothermal Generators.
+
+## Centrifuge cost
+
+| Item | For 1 Centrifuge | For 1 Stack | For 3 Stacks |
+---|---|---|---
+refined iron | 31 | 1984 | 5952
+redstone | 14 | 896 | 2688
+copper | 9 | 576 | 1728
+rubber | 18 | 1152 | 3456
+glowstone | 4 | 256 | 768
+lapis | 4 | 256 | 768
+advanced alloys | 4 | 256 | 768
+coal dust (for carbon plates) | 32 | 2048 | 6144
+planks | 20 | 1280 | 3840
diff --git a/material_calculations/titanium_calcs.md b/calculations/titanium_calcs.md
similarity index 100%
rename from material_calculations/titanium_calcs.md
rename to calculations/titanium_calcs.md