When there's no sunlight, solar panels can't generate electricity. This highlights the importance of solar backup batteries to guarantee a continuous power supply even when there's no sunlight.
The cost of a wind turbine varies widely based on size and project specifics, but generally ranges from a minimum of $15,000 for a small residential rooftop unit up to $4 million or more for an industrial multi-megawatt utility-scale turbine, with most commercial installations.