Large solar panels are great from producing a lot of power, but they also take up a lot of space. This results in the panel potentially blocking several adjacent docking ports. Alrik Fons and the Part Development Group at Centauri Spaceworks have created a solar panel which solves this problem.
The half solar panel produces 50 power and consumes 2 power giving it a net output of 48 power. This makes it the least powerful dedicated solar panel (excluding the MSS Sensor module which also is a pressurized module).
The advantage of the half solar panel is that it has three docking ports, more than any other solar panel. These allow it to be attached in a variety of configurations. It can be positioned to open directly out from the attached docking port like the MSS Solar panel (but has a much smaller clearance when retracted).
It can also be positioned to open perpendicular to the attached docking port. This leaves one side of the half solar panel still clear and available for other modules to be attached. No other solar panel has this capability.