Storage & flexibility
Power is the rate.
Energy is the duration.
A battery can shift when electricity is used or supplied. It does not create renewable energy; the charging source and operating strategy matter.
Separate MW from MWh
MW describes the rate of power delivery. MWh describes the amount of energy. A 10 MW battery delivering for four hours supplies 40 MWh before allowing for losses and operating limits.
Define the service
Identify whether the priority is peak management, shifting renewable output, resilience or market participation. A single system may face competing operating commitments.
Make losses and limits visible
State usable capacity, efficiency, degradation and reserve assumptions. Check power electronics, connection capacity, safety and applicable operating rules with specialists.