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.

Resistors (Ω) oppose current, are color-coded, and connect in series (Rt = ΣR) or parallel. Current-limiting resistors protect LEDs.

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.