The researchers found a reliable way to study how energy is used in photosynthesis. They treated chloroplasts with certain chemicals to stop water oxidation without affecting the energy transfer process. They observed no change in the efficiency of energy transfer until the reactions stopped. Other reactions in the chloroplasts were not affected by this treatment. The researchers also showed that the treated chloroplasts could still produce energy with the same efficiency as normal chloroplasts. This study helps us understand how plants convert light into energy.