Help i think its wrong but k

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1.Type of energy resource that will never run out - 6 letters

2.Type of energy resource that will never run out - 9 letters

4.Using the Sun’s energy to heat water - 5 letters

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3.Ethanol is an example of this type of fuel - 7 letters

5.The burning of these fuels releases carbon dioxide - 6 letters

6.Burning trees is described as carbon ... - 7 letters

7.Damming rivers to generate electricity - 5 letters

8.The energy comes from splitting atoms - 7 letters