To handle half the world's avg electricity use, I estimate it would take a ~3ft thick copper cable at 1.1Mv hvdc. This ignores the heating of cable which might become a problem. Also you might need two of these unless you want do earth return.

global_consumption_joules = 22848E12 * 3600

seconds_per_year = 365.25*24*3600

avg_power = global_consumption_joules/seconds_per_year

hvdc_voltage = 1100E3

amps = (avg_power*.5)/hvdc_voltage # assume shiping half the power to dark side of planet

sq_in_copper = amps/1000 # 1000A/sq in of copper

dia_in = (4*sq_in_copper/3.14)**.5

print(dia_in/12) # 3.23ft dia of cable

This seems very thin. The planned Sunrise Australian Singapore cable, ~5000km, ~5GW, this is 1/1000th of the power, so a cable 1/30th as thick? Under 2 inches???

Anyway - can you maybe lend a quick hand for a more practical calculation?

How do we move 10MW DC, from a battery pack, to a motor 200m away? Can i just hook the batteries in parallel and get to 10Kv ?!

Obviously a liquid cooled cable.

Area increases as a square of diameter, and the square root of 1000 is 31, so 1/30th as thick seems about right.

Current state of the art battery packs run at 800V. Making a 10kV pack would be difficult. 10MW is about the size of the largest wind turbines so maybe a wind turbine engineer could help you.

The usual method is to increase the voltage, rather than the wire gauge. That's why we have 1.1 million volt transmission wires.