# How do I calculate what 80 RF is in MJ?

In FTB direwolf I have a setup of steam dynamos that put their power to a Tessaract. the Tessaract runs my quarries and I want to know how many dynamos it takes to power my quarries.

I want to calculate the difference between 80 RF and what that is in MJ.

I don't need to convert it because that is what the Tessaract is for.

Quarries run on Minecraft Joules, or MJ.

RF converts to MJ at a rate of 10:1, so 80RF is 8 MJ. Also, you don't need a tesseract to convert RF to MJ, you just need an energy conduit that is connected to a MJ consuming machine.

As for how many dynamos you need to power a quarry, quarries take up to 100MJ per tick (MJ/t), but will run perfectly fine on 25MJ/t.

To produce 100MJ/t, you will need 13 dynamos, which will be capable of producing a total of 104MJ/t (1040RF/t). They'll auto-throttle to produce only as much as is requested, so one will likely only run at 4MJ/t (40RF/t).

• Sorry I used the wrong constants. I use a tessaract because I have all dynamos at the farm, where the steam is at. I know I can transport the fuel instead of the energy. But I like this way better. Commented Jan 29, 2014 at 17:20
• Just a note: tesseracts are lossy (25%) so you'd need more than what the quarry consumes to make up for it. Commented Jan 29, 2014 at 18:37
• @NathanC I only use 2 steam dynamos to run 2 quarries... and that works, which makes the 25MJ trigger bullshit or this ratio is wrong.. Commented Jan 29, 2014 at 20:00
• @Alvar Well, it takes off 25% when you output (so, input 100 MJ/t and you'd only get 75 MJ/t output on a single line). That said, it probably doesn't reach that threshold yet. Commented Jan 29, 2014 at 20:02
• @Nathanc well how do you explain that two dynamos can run 2 quarries then? They don't even reach the 25MJ trigger... Commented Jan 29, 2014 at 20:11