Secondary active transport is powered by energy from

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Secondary active transport works by using energy stored in an existing ion gradient to move another substance uphill. In this process, the transporter couples the downhill flow of an ion (commonly Na+) down its electrochemical gradient to the uphill transport of a second molecule against its gradient. That gradient was created earlier by primary active transport, which uses ATP to move ions against their gradients. A classic example is the Na+-glucose cotransporter, where Na+ moving into the cell down its gradient helps bring glucose along, even though glucose itself would move against its gradient.

Direct ATP hydrolysis isn’t the immediate energy source for the transporter in secondary active transport—ATP powered the gradient beforehand. Light energy and thermal energy aren’t the direct energy driving this mechanism in the typical cellular context.