The answer to this question depends on various factors such as location, availability of resources, energy demand, etc. Overall, solar energy is becoming more affordable and practical, thanks to advances in technology and the falling cost of solar panels. Wind energy is also cost-effective, but it requires large turbines and open space, making it less practical in some places.

In desert areas, solar power can be very efficient because there is plenty of sunlight and little wind. And near coastlines, where wind speeds are higher, wind turbines are more efficient, because solar energy may be less affected by clouds and rainy days.

For example, let's consider two scenarios:

Case 1: A rural area in Arizona has an average of 300 days of sunshine per year. Solar panels would be the cheaper and more practical option, as there would be plenty of sunlight for most of the year. Wind turbines are not efficient because the wind is unstable.

Case 2: A coastal area of California where winds are strong and constant. Wind turbines would be the cheaper and more practical option because there is always wind to produce energy. Solar panels are less efficient in this location because of cloudy weather conditions.