Here are a bunch of LEDs connected in parallel such that the current from each LED adds to the total current. This LED bank is connected to a solar power calculator with the solar cell removed.

Two drivers in parallel provide twice as much current and split power loss into two locations, which makes for easier heat dissipation.

A power-limit circuit can be added to the circuit in Fig. 1 to limit the overall power when there is a large voltage variation for parallel strings of LEDs, with the result shown in Fig. 2.