(the aerodynamics is twisted form alleviating the effects of vortex-shedding)
We've had good results with Parmak, both solar and line powered. Go with line power if you possibly can.
Even if you're buying another brand, download and print out this manual: http://parmakusa.com/download/Parmak...et_English.pdf
It has one of the best set of grounding instructions for soil with poor conductivity. Details start around page 4.
About the electricity source -
If you just have an electric company pole that holds wires there, you need to have a service installed. Must be done by an electrician, inspected, approved - not cheap.
If you already have service, and electrician can install an exterior receptacle for your charger. You still need a protected place in which to install it.