12.1 – NOTES Energy:Past and Present

Petroleum is nonrenewable People need alternative forms of energy  

D.1 Energy: Past and Present Sun is the planet’s primary energy source Radiant energy – energy from sun (solar energy) is stored in plants through photosynthesis   Plants convert CO2 and H2O into Carbohydrates and O2 gas This type of energy is chemical potential energy Energy is released and used by animals

Organic molecules found in plants/animals Biomolecules Organic molecules found in plants/animals   The digestion of plants is overall exothermic More energy is released by forming products than breaking them down

Solar energy and energy in biomolecules are key energy sources for life on earth Up till 1850 Natural energy sources, such as biomass, were used including wood, water, wind, and animal power   Reasons for needing other fuel sources included: Industrialization Population Increase