Final answer:
Between 350 and 300 million years ago, the Earth received extensive solar energy, contributing to widespread plant growth and the formation of fossil fuels, representing stored ancient solar energy that impacts today's renewable energy budget.
Step-by-step explanation:
The Earth's energy budget between 350 and 300 million years ago was fundamentally influenced by the amount of solar energy received from the sun. During this time period, which encapsulates part of the Carboniferous Period, the Earth's flora underwent a significant expansion, particularly with the growth of vast swamp forests that eventually formed today's fossil fuels. As the sun sends energy toward the Earth at a rate of 1,360 W/m2, much of this energy was captured by plants during photosynthesis and stored as organic matter that would become coal and oil over millions of years. This process of ancient solar energy storage played a critical role in shaping the renewable energy budget of the planet long before human society began utilizing these resources for energy needs.