Answer:
Water,something that looks like a bag and something that looks like smoke.
The bag and water are both in solid and liquid respectively and also the smoke is gaseous.So am not sure of the two substances that you need but I have listed them.Thank you for the question
In order to create a hydroelectric power plant, you need water, hence the prefix hydro-. Most times, people use dams to block the water, which in a way stores it. When you need to produce electricity, you release some of the water which flows through a turbine making it spin, which then activates a generator to produce electricity.