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I'm building Smart Furnace based on that topic (viewtopic.php?f=8&t=25615&start=10#p163551) and designed furnace tile when I have 10 Beacons per Furnace Now I would like to know what it the best Modules setup for that?
Productivity Modules will be placed in Furnaces.
I could insert in Beacons only Speed Modules and get +500% speed but +700% energy consumption is HUGE.
I would like to maximize speed but with reasonable energy consumption.

+700% energy consumption is not very big at all actually, this is because the quicker an item is crafted the less energy it takes to make it, in accordance with this formula:

energy = watts * time

Say we're crafting a recipe with a time of 3.5s, in a furnace with the following stats:

Crafting Speed: 2
Energy use: 180kW

180kW * (3.5s / 2) = 315kJ / item


Now lets crank it up with +500% speed (x6) and +700% (x8) energy use.

Crafting Speed: 2 * 6 = 12
Energy use: 180kW * 8 = 1440kW

1440kW * (3.5s / 12) = 420kJ / item

The energy use per item has increased by a mere 420kJ / 315kJ = 33%

Of more concern is the energy from the 10 beacons. Each beacon uses 480kW, assuming each beacon is shared over 2 furnaces that leaves 10 * 480kW / 2 = 2400kW, that needs to be added to the base machine energy:

Crafting speed: 2 * 6 = 12
Energy Use: 180kW * 8 + 2400kW = 3840kW

3840kW * 3.5 / 12 = 1120kJ/item

Now the energy use per item is +255%, but nearly all that increase is from the beacons, not the energy use of the furnace. The energy use of the beacons can be slashed by sharing them, the alternating rows layout is popular because each furnace benefits from 8 beacons, this cuts the beacon overhead to 12.5% of what it would be for a single furnace.

When using 10 beacons per furnance there is nothing you can do to make the energy use more reasonable except not use so many beacons, maximizing beacon sharing is the only way to make beacon energy use reasonable while furnace/assembler energy use tends to be reasonable no matter what you do just because of how the module effects works.

I would say putting Productivity in the furnaces and all Speed in the beacon's is fine, especially if you are on solar power. Since the energy from solar is essentially free (aside from the cost of making them obviously), then I would say don't worry about the extra power consumption and just build more panels and Accumulators if need be.

However if you are really pressed for power and not as worried about the larger production amounts then maybe put efficiency in half the beacon's of something to try and balance it out.

Xterminator wrote: However if you are really pressed for power and not as worried about the larger production amounts then maybe put efficiency in half the beacon's of something to try and balance it out.

That wont work. Efficiency works really poorly in conjunction with productivity, in fact speed usually offers greater energy savings than efficiency by making the production cycle faster.

I did work out a while ago how horrible eff modules are in beacons. It's easy to calculate. A beacon uses 480kW, that means the eff modules need to save at least 480kW to be better than not having the beacon (a much cheaper alternative). You can simply calculate the base kW of the machine, multiplied by the eff module effect:

Beacon savings for Electric furnance @ 180kW:
2xEff1: 30% = 54kW saved (needs to cover 8.8 Furnances to get 480kW)
2xEff2: 40% = 72kW saved (needs to cover 6.7 Furnances to get 480kW)
2xEff3: 50% = 90kW saved (needs to cover 5.3 Furnances to get 480kW)

Eff beacons can be quite accurately described as the most expensive way to save electricity. Technically in alternating rows layout Eff2 and Eff3 beacons can save a little electricity, but at a cost so much greater than it would take to generate that power by solar/accu.

But to add insult to injury, Speed2 and Speed3 beacons can actually save more energy than the same tier of eff module.

Electric Furnace @ 180kW with 2x Prod3 module:

468kW, crafting speed = 1.4, energy per item second = 334kW

Electric Furnace with 2x Prod3 module, and 1x Speed3 Beacon (shared over 8):
594kW, crafting speed = 2.4, energy per item second = 247.5kJ (+60kW for beacon = 272kJ)


Electric Furnace with 2x Prod3 module, and 1x Eff3 Beacon (shared over 8):
378kW, crafting speed = 1.4, energy per item second = 270kJ (+60kW for beacon = 312kJ)

Yep, eff3 modules are so absolutely sh*t that not only do they barely break even, speed3 modules save at least 15% more energy. While, you know, making production much faster. Yes, there is something terribly wrong with eff module design. Or perhaps speed modules are overpowered. But in any case using eff modules in beacons is a terribly poor strategy.

Thanks everyone for help. I did some calculations and it seems that 8 beacons per furnace is the best setup.

In that way most of the beacons share bonus with 2 furnaces and some share witch 4 furnaces.
Adding beacons horizontally between furnaces allow to get a little more efficient but it's too low compared to costs (2x more beacons and modules).