Efficiency

• Efficiency= useful energy output/ total energy input x 100(for percentage)
• devices that waste as little energy are efficient and devices that waste the majority of the total energy are inefficient
• lubrication= reducing friction between two things that rub together reducing thermal(wasted)energy (for example oil for rust)
• Insulation=Reducing the amount of thermal energy that transfers into surroundings, allowing the heat to be more concentrated
• Reneweable Energy= Energy that can be reused again and again without being used up.
• Solar


  Produced by the sun, No Co2 produced, unreliable in certain countries
• Hydro


  Produced by rivers and streams, No Co2 produced, destruction to habitats(damns)
• Turbo


  Produced by Wind, No Co2 produced, Very noisy
• Tidal


  Produced by sea waves, No Co2 produced, expensive
• Nuclear


  Produced using Nuclear power, No Co2, Very reliable and clean, Dangerous(use of Radioactive chemicals)
• Bio Fuels


  Produced from natural living materials(animal faeces, corn ethanol etc) No Co2 Produced, Doesn't produce much energy
• Fossil Fuels

  Produced from oil, gas and coal, Non-renewable, Produces Co2-global warming, Produces a lot of energy
• A rise in temperature in a mechanical process is caused by the transfer of wasted energy