why is electricity is not sent in smaller voltages from the power station rather than substation?

Question

why does the sub stations smaller the high voltages, why aren't they sent in smaller voltages from the power station?

Answer 1

For a given power output, the higher the
voltage the lower the current. The lower
current means less I^2*R loss.

P = E*I = 100 * 10 = 1000 W.

P = 1000 * 1 = 1000 W.

Note: When E is increased to 1000 volts, the current is reduced to 1A.