When using solar power, you do not have to worry about harming the environment in any way. Fossil fuels send harmful greenhouse gases off into the atmosphere, and they contribute to global warming and climate change. However, solar cells have no impact on the environment and are safe to use.
Webpage, schematics http://bristolwatch.com/solar2.htm.
Since children are the ones who will be running the future it is important to teach them early about renewable energy. As a parent you can set the example by using solar energy whenever possible. If it is not possible to swap your entire house over, maybe switch out your outdoor lighting.