Which two energy sources require open space?

The correct answer is: Wind and solar power

• Solar energy is any type of energy generated by the sun. Solar energy is created by nuclear fusion that takes place in the sun
• Biomass is plant-based material used as fuel to produce heat or electricity. Examples are wood and wood residues
• Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions
• Wind power or wind energy is mostly the use of wind turbines to generate electricity
• So from above definition  we can say solar energy requires open space so that sun rays can come and also in wind energy we requires  open space because we want wind to move the turbine 
• So answer is Solar power and Wind