Steam Grinder

The Steam grinder is a macerator multiblock added by GT++. Although it behaves much like other GT++ multiblocks, it is notorious for being available at the steam age, being powered by steam rather than EU, and not needing maintenance.

Construction
The steam grinder is a 3x3x3 hollow multiblock. The controller must be placed in the front center. It requires steam-tier input and output buses ("Input Bus (Steam)" and "Output Bus (Steam)", respectively), and a steam hatch. Higher-tier hatches and buses will not work. The other blocks are bronze plated bricks. It can have multiple buses and hatches, but at least 14 blocks (out of the 26) must be bronze plated bricks.

Crafting the bronze plated bricks and the input and output buses needs only tin, copper, gold, and clay. The controller also requires 2 diamonds and 2 pistons, and the steam hatch needs one steel plate.

Speed and Energy Consumption
The steam grinder is capable of processing exactly the same set of recipes as the single-block Steam Macerator, but faster, with reduced power cost, and with parallel processing.

Recipe times are reduced by 25% (i.e. multiplied by 0.75), and rounded down to the nearest tick. For example, pulverizing oak logs normally takes 800 ticks (40 seconds); the steam grinder grinds them down in 600 ticks (30 seconds). Triple electrum plates take 906 ticks (45.3 seconds) to be pulverized in a steam macerator, and $$\lfloor 906 \times 0.75 \rfloor = 679$$ ticks (33.95 seconds) to be pulverized by a steam grinder.

Energy usage is reduced by 33% (i.e. multiplied by 2/3), and rounded up to the nearest integer. For example, pulverizing coke oven bricks uses 60L steam/tick in a steam macerator, and a steam grinder requires only 40L steam/tick. Sand requires 14 L steam/tick to pulverize in a steam macerator, and $$\lceil 14 \times (2/3) \rceil = 10$$L steam/tick to pulverize in a steam grinder.

Note that the energy usage discount stacks with the recipe time reduction, so the overall steam cost is approximately reduced in half.

The steam grinder is capable of processing the same recipe up to 8 times in parallel, proportionally raising the cost. However, the cost scaling is calculated before the rounding performed in the previous step. For example, placing an entire stack of oak logs in the input bus will make the grinder process them 8 logs at a time. Oak logs need 4L steam/tick to be pulverized; this would be scaled up to 32L steam/tick, but, due to the discount, the steam grinder uses $$\lceil 8 \times 4 \times (2/3) \rceil = 22$$L steam/tick.

Finally, observe that steam hatches can only provide about 40L steam/tick to the steam grinder, which limits the parallel processing. For example, pulverizing charcoal takes 8L steam/tick in a steam macerator. Processing 8 at a time in a steam grinder would require $$\lceil 8 \times 8 \times 2/3 \rceil = 43$$L steam/tick, which is more than 40, so the steam grinder only pulverizes 7 pieces of charcoal at a time. Sand can only be processed 4 at a time, as pulverizing 5 sand would require $$\lceil 5 \times 14 \times (2/3) \rceil = 47$$L steam/tick. And anything that costs more than 32L steam/tick to pulverize (like coke oven bricks) gets no parallel processing at all; for these recipes, the steam grinder is actually slower than a single High Pressure Macerator. Adding more steam hatches to the grinder does not help, as the grinder only pulls steam from one hatch at a time.