Here's another example. What is the power output of an electric kettle connected to the 230 V mains, when a current of 10 A flows?

P = I × V = 10 × 230 = 2,300 W

For larger numbers, we can simplify this using the prefix kilo (k):

P = 2,300 W = 2·3 kW.

When talking about power from a wind turbine or power station generator, we talk about megawatts (MW) or even gigawatts (GW)!