SOLAR - WIND - giving back to the grid

For anyone in the know, what's involved with setting up a renewable electricity source and giving back to the power grid? I can get my hands on 300W 24V wind turbine generators. Is this suitable for giving back to the grid to reduce by lecky bills? How do I go about getting this installed and set up and is 300W 24V appropriate? Or do I have to use solar panels only? Can I use both? Anyone with any information, please let us know. I'd like to learn more about this topic.
Other questions I have is, do I need batteries and an invertor or is that only if I'm going to use my generate power myself. Also, how much work will a sparky do on an installation like this before an expert in solar panels/wind turbines, needs to be called in?


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