The A1 is a 256 mm bed-slinger with a direct-drive extruder, a 300 °C hotend and no enclosure. Its combination of a large-ish bed, a hardened stock nozzle and an open frame decides both what it can print and what it costs per hour, and those two things pull in opposite directions.
Power, and where the alarming numbers come from
Metered figures for this machine settle around 100 W while printing, with roughly 10 W at idle and a transient peak in the region of 350 W while the bed comes up to temperature.
Published figures in the region of 1300 W circulate for this printer. That is a supply rating, not a consumption figure, and treating it as one overstates a real print by more than ten times. The distinction matters because it is the difference between a long print costing a few cents and appearing to cost a few dollars.
The steady-state figure is what the cost calculator uses. On a 12-hour print at a US average residential rate, 100 W works out to well under a quarter of a dollar — which is usually a small fraction of the filament cost, and is exactly why the electricity term is worth computing rather than guessing in either direction.
What the open frame rules out
No enclosure means no ABS, no ASA and no polycarbonate at any useful size. Those materials contract enough as they cool that ambient draughts alone will lift a corner off the plate, and a cardboard box over the machine is a mitigation rather than a solution when the bed is this wide.
What the frame does not rule out is a large slice of everything else. PLA and its blends, PETG, TPU and filled PLA and PETG all print well on an open machine, and between them they cover most of what people actually make.
The 256 mm bed, both ways
A large heated bed is the single biggest lever on running cost, because bed area is what the machine spends most of its electricity holding at temperature. The A1's bed is more than twice the area of a 180 mm machine's, and it loses heat to the room continuously because nothing encloses it.
In exchange, it fits parts that a smaller machine cannot, and it lets you batch small parts — which is worth knowing for a different reason: printing four copies at once gives each layer time to cool, which fixes the melted-small-features problem you would otherwise chase through cooling settings.
Practical notes
The stock nozzle is hardened, so filled and abrasive filaments are available without buying a part first. That is unusual at this price and it removes the most common reason a first carbon-filled spool goes badly.
As a bed-slinger, the machine moves the print back and forth on the Y axis, so tall thin parts are more prone to ringing and to being knocked than they would be on a machine that moves only the toolhead. Reducing acceleration before reducing speed is the effective response, because acceleration is what excites the frame.
Getting an accurate estimate for this machine
Two inputs matter more than everything else combined: the density in your filament profile, and your own electricity rate. Set the first from the material page for the spool you actually loaded rather than leaving whatever the profile shipped with, and set the second from your own bill rather than a national average.
With those two right, an estimate for this printer will usually land within a few percent of a weighed result, which is more than good enough for pricing work.