Mighty Mule® solar power guide How practical solar power is for your Mighty Mule® gate opener needs to be examined on a case-by case-basis. Factors to consider are: location of gate, type of gate, frequency of use, and how far the gate opener is from a power source etc. Therefore, if you are within a 1000 ft of a power outlet, we recommend using the transformer that is included with your Mighty Mule Gate Opener. This will provide you with the most consistent charge than you would get from solar charging power. After all options are considered and it is determined that solar charging is your best option.— See charts below for the recommended number of solar panels based on your model, climate zone, and frequency of use. The table and map below illustrate the maximum number of gate cycles to expect per day in a particular area when using solar charging panels with all Mighty Mule® models. Up to 30 Watts of solar charging power for Mighty Mule® models FM500, FM502 and FM350. Installing an optional second battery is recommended for best performance of your gate opener. The chart figures are based on winter sunlight (minimum) and do not account for any other accessory items installed with your opener that draws additional power from your battery.   Mighty Mule® Solar Chart           Accessories Packaged Systems