What overarching statement best describes what is being studied? what general statement includes what is being studied? it's about renewable energy.

Here is an essay I wrote on renewable energy feel free to use some of it:
Solar power:1. The definition of solar power is power obtained by harnessing the energy of the sun's rays.2. Using solar power can be better for the environment than coal. It is local.3. Solar power can be very expensive. There isn’t always sun, so we can not always get power from this resource.4. Solar power plants take up land often resulting in habitat loss, and some use hazardous materials in making solar power panels.5. Using this resource is better for the environment than using coal, but since there isn’t always sun, we can not always get power from this resource.6. Solar power cost more to create and to use than coal does.
7. Photovoltaics (PV) and concentrated solar power (CSP) are used to collect energy from the sun.
8. The sun hits the solar panels and generates DC electricity. The energy then goes into a solar inverter that turns the DC energy into AC energy, which is then used to power things.
9. Two potential hazards in using this resource are the materials used to make it, and habitat loss.
10. If solar power were our primary way of getting electricity a lot of land would be taken up by the solar power plants, resulting in the loss of a lot of animal habitats. Also, the sun isn’t out 24/7, so we can not always get power from this resource.
Since I believe that our country is already headed in this direction anyway, I would suggest that we invest in the use of more renewable resources. I would suggest that we use geothermal as our main way to get our hot water for our homes, hydropower for electricity in states with an abundant water supply, and the combination of wind and solar power for electricity as well. I think we would have cleaner air and it would be more efficient. Both renewable and non-renewable have their pros and cons, and I personally believe that in this day and age we would have a hard time functioning without both of them. But I do think that using more renewable resources would be a good investment.