Question

Where are the ATP and NADPH used..?

Answer 1

The ATP and NADPH used in these steps are both products of the light-dependent reactions (the first stage of photosynthesis). That is, the chemical energy of ATP and the reducing power of NADPH, both of which are generated using light energy, keep the Calvin cycle running.

(Hope it helps)

Answer 2

The ATP and NADPH are generated using Light energy. They keep the Calvin cycle running.