After I got some interesting numbers out, I was able to wrangle them into an over-unity device. (Sadly not a perpetual motion machine since it can't use the rocket fuel as an input)
Now you can run your trains both FASTER and FURTHER on the same amount of fuel!
The circuit network is rigged to power up the factory and beacons when the input chests are sufficiently full to guarantee both factories have feedstock and the output chests are not overfull. Until then, only the inserters pulling the completed rocket fuel out are powered by the large poles.
Inputs:
2500 MJ worth of solid fuel (100 cubes)
<1 MJ electricity for inserters and circuit network
------
2952 MJ (~
Time:
Outputs:
3150 MJ worth of rocket fuel (14 boosters)
Net Gain:
198 MJ (423 MJ if using solar)
Solid->Rocket Fuel Conversion Efficiency:
107% (Boilers)
116% (Solar)
Blueprint String
NOTE:If there is an arrangement of beacons which allows a 7th to boost both factories, that will be even more efficient.
Using 8 beacons to impart 7 effects reduces efficiency.
EDIT:
Math did not include the 1.25 base crafting speed of the assembly machine.