The level of the food web that has the most energy is the producer level. Producers, such as plants, algae, and some bacteria, are at the base of the food web. They convert sunlight into chemical energy through the process of photosynthesis. This energy is then stored in the form of glucose and other organic compounds.
When consumers, such as herbivores, eat these producers, they obtain this stored energy. However, not all the energy is transferred to the next level. In fact, only about 10% of the energy is passed on to the next trophic level. The rest is lost as heat or used by the organism for its own metabolic processes.
As you move up the food web, from producers to primary consumers (herbivores), to secondary consumers (carnivores), and so on, the amount of available energy decreases. This is why there are usually fewer top predators in an ecosystem compared to the number of producers.
In summary, the producer level has the most energy because it is the first level where energy from the sun is captured and stored. This energy then flows through the food web, decreasing at each subsequent level.