Technically, the person you replied to is correct. Energy / time (energy over time) is power. Power * time is energy.

If you had a battery with 20kWh and it was empty after two hours, you would know that it was providing 10kW, which is a measure of the energy released over time, aka. average power.

I don't think nynx's comment made things much clearer to anyone, though.

1W=1J/s ... energy per unit time.