73. Fill in: Is there a better way to store energy than inside batteries?
74. Fill in: They use wind power to generate electricity.
75. Fill in: If you compress the air, you can fit more inside the chamber.
76. Fill in: We are trying to eliminate the problems in the system.
77. Fill in: We pump the water to a higher point and collect the energy as it runs back down again.
78. Fill in: The amount of energy our solar panels produce can fluctuate by as much as 90 % depending on the weather.