Watts to Wh calculation formula
E(Wh) = P(W) × t(h)
The energy E in watt-hours (Wh) is equal to the power P in watts (W), multiplied by the time period t in hours (h).
Wh = W × h
watt-hour = watt × hour
Power (P) = 250W
Time period (t) = 5h
Energy (E) = 250W x 5h = 1250Wh