Understanding Energy Transformation and Types

• Energy is defined as the ability or capacity to do work, or the power from something that provides light and heat
• People use energy for diverse purposes like walking, transportation, cooking, manufacturing, and space travel
• Energy transforms but is neither created nor destroyed, a concept known as the conservation of energy or the first law of thermodynamics
• Energy can be converted; for instance, the chemical energy in food becomes kinetic energy during activity, and can exist in forms like heat, light, motion, electricity, chemical, and gravitational
• Modern civilization relies on the ability to transform energy for various tasks

Types of Energy

• Potential (stored) and kinetic (working) energy are the two general types of energy for doing work
• Energy is measured in joules in the International System of Units (SI), where one joule equals the work done by a one-newton force over one meter

Energy Conversion

• Energy can be converted using devices such as magnetic circuits, transformers, fuel-burning heat engines, generators, motors, and batteries
• Solar power converts the sun's energy into heat and electricity

Background

• Michael Faraday discovered electromagnetic induction in 1831 and later invented the first generator
• Electric energy technologies are central to social and economic development
• Energy usage is tied to environmental pollution, economic development, and quality of life
• Dependence on nonrenewable fossil fuels causes pollution and climate change, necessitating sustainable alternatives

Energy Resources

• These resources provide heat and electricity, they include oil, gas, coal, wood, wind, waves, sunlight, and geothermal heat

Renewable Energy

• Renewable energy is sustainable and endless, like solar power, and are alternatives to non-sustainable sources like coal
• Sunlight, wind, rain, tides, waves, and geothermal heat are examples of renewable energy replenished on a human timescale
• Renewable energy is used for electricity generation, heating/cooling, and transportation
• The most popular renewable energy sources include solar, wind, hydro, tidal, geothermal, and biomass

Classification of Energy

• Conventional energy has been used for long time and is well-established with available technology, including coal, oil, natural gas, hydro, and nuclear

• Non-conventional energy is advantageous for power generation and other applications, but cannot be easily stored, and includes solar, wind, tidal, and geothermal

Non-Renewable Energy

• Non-renewable energy sources are exhaustible, including oil, natural gas, coal, and nuclear energy

• Countries rely on fossil fuels like coal, oil, and natural gas, as well as nuclear for energy

Natural Resources

• These include oil, gas, coal, wood, wind, sunlight, and waves, for energy production

Oil and Natural Gas Formation

• Oil and natural gas form from marine plants and animals that died millions of years ago
• Dead organisms sink, and become buried under sediments like sand and mud
• Over time, sediments get buried deeper, temperature and pressure increases, turning microorganisms into gas and oil
• Oil and gas move through rock pores, gets trapped under impermeable rock layers and is extracted with drills

Oil and Gas Usage

• Crude oil becomes jet engine oil, petrol, and diesel for vehicles.
• Burning releases carbon dioxide, a greenhouse gas linked to global warming

Coal Formation

• Coal formed during the Carboniferous Period from tropical swamps about 360-299 million years ago

• Dead plants turned into peat during the Jurassic Period, 201-145 million years ago

• Over time, peat turns into coal with heat and pressure

Coal Usage

• Coal is burned to heat water and propel turbines to generate electricity

• Burning coal is cheap and abundant, but releases carbon dioxide, sulfur dioxide, and nitrogen dioxide, contributing to global warming

Nuclear Reactions

• Uranium and plutonium are nuclear fuels, nuclear fuels don't produce harmful greenhouse gases and are efficient

• Nuclear power generates radioactive waste needing containment for thousands of years

Renewable Examples

• Biomass is renewable, and so is Geothermal, solar, and wind energies

Wind Turbines

• Large windmills are called wind turbines that convert wind into electricity

• Wind farms in windy areas use many wind turbines

Solar Energy

• Solar energy from sunlight can generate heat or electricity

• Solar panels, filled with water, or photovoltaic cells use sunlight to produce heat or electricity

• Solar panels can be installed on building roofs but are expensive

Geothermal Energy

• Geothermal energy heats the Earth when water can be pumped down into hot rocks to be heated

• It can be used to produce heat or electricity and is a popular source in volcanic areas like Iceland

Geothermal Energy facts

• Geothermal energy has been used for thousands of years for bathing, cooking, and heating and is found most often and effectively in volcanically active areas

• Geothermal power plants utilize heat from deep inside the Earth to generate steam for electricity

• Geothermal heat pumps tap into heat near the Earth's surface to heat water or buildings

Geothermal Heat Pumps

• They use water or refrigerant through underground pipes at a constant temperature of 50 to 60°F

How Geothermal Heat Pumps work

• Water or a refrigerant circulates in loop of pipes and heats up while buried underground in cold weather
• This warmed water or refrigerant transfers heat into the building before cooling down and pumping back underground
• In hot weather, the system reverses, cooling the building and transferring heat to the ground

Hydroelectric Power

• Hydroelectric dams trap water in reservoirs to harness running water's energy
• Water flows with gravity to spin a turbine when electricity is needed.
• It is more reliable than solar and wind power, but can be expensive and harm wildlife

Tidal Power

• Tidal energy is a form of hydropower converting energy from tides into electricity

• Although among the renewable energy sources, tidal energy tends to be more expensive and has less viable locations

Biomass Energy

• Biomass is renewable energy from plants and animals, and was the largest source of total annual U.S. energy consumption until the mid-1800s

Current uses of Biomass energy

• Biomass is still used for cooking and heating in many countries

• It is also used for transportation and electricity that mitigate carbon dioxide from fossil fuel usage.

• Forestry crops, residues, sewage, municipal solid waste, agricultural crops, residues and animal residue are feedstock examples

Biomass Fuel Sources

• Firewood, wood pellets, wood chips, lumber, and furniture mill sawdust and waste, and black liquor

• Agricultural crops and waste materials include corn, soybeans, sugar cane, switchgrass, woody plants, algae, and crop and food processing residues

• Biogenic materials in municipal solid waste are paper, cotton, wool, food, and wood wastes

• Animal manure and human sewage is another source

Biomass Information

• Biomass is organic material from living organisms, known as biomass feedstocks

• It is a renewable source since trees, crops, and waste are consistently available

• Due to the abundance of plants, it is seen as a suitable alternative to fossil fuels

Biofuel

• Biofuels are liquid fuels or components from biomass materials
• Biofuels serve as transportation fuels and for heating and electricity
• Biomass converts to liquid or gaseous biofuels through the fermentation of crops that are high in sugar or fat into ethanol
• Ideally, biofuel should be carbon neutral

Recycling

• Recycling saves energy, and even saves energy when compared to the production of everyday products like food containers, smartphones, computers and cars.