Presentation on theme: "Introduction to Energy Concepts. Energy Derived from Green en (in) and ergon (work) – in work Forceful or vigorous language First definition - Aristotle."— Presentation transcript:
Introduction to Energy Concepts
Energy Derived from Green en (in) and ergon (work) – in work Forceful or vigorous language First definition - Aristotle Capacity to do Work Modern accepted definition Energy is Eternal Delight William Blake,
Four Basic Forms of Energy Kinetic = 0.5 x mass x speed 2 Thermal – energy of vibrating molecules within a material Electrical – force between electrical charges Chemical – electrical energy that holds molecules together Gravitational – also known as potential energy – force x distance = weight x height = m x g x h Nuclear – forces that hold atoms together
Units of Energy Energy requires a force. Each form of energy has it s own force: gravity, strong & weak nuclear forces, electrical, and kinetic forces. Kinetic Force = Mass x Acceleration Unit of force = 1 Newton = 1 Kilogram x 1 m/s Energy is a measurement of work accomplished by a force Energy = Force x Distance 1 Joule = 1 Newton x 1 Meter
Energy and Power Energy is a quantity, like distance. 1 kilowatt-hour = 1000 Watts x 1 hour 1 kilowatt-hour = 3.6 x 10 6 Joules Power is a rate, like speed, it is the rate that energy is converted from one form to another. 1 Watt = 1 Joule / Second
Laws of Thermodynamics First Law: In any transformation of energy from one form to another, the total quantity of energy remains unchanged. Energy is neither created nor destroyed, it only changes forms. Second Law: In all energy changes, the potential energy of the final state will be less than that of the initial state – (useful energy is always lost.) Lost energy is usually energy that has been converted to heat, but it could be noise (kinetic energy of air), or other forms of wasted energy.
Efficiency The ratio of the amount of useable energy obtained to the amount of energy input is the efficiency of a process. This is usually expressed as a percent and it is always less than 100%.
Energy definitions Primary Energy – amount of energy contained in the initial source of energy Delivered Energy – amount of useable energy delivered to the customer Useful Energy – amount of energy attributed to the amount of work accomplished
Where do we get energy from and what do we use it for?
Renewable vs Non-Renewable Solar Wind Biomass Hydro Ocean Coal Oil Gas Nuclear
Fuel is not getting any cheaper..
1000 years of CO2 Concentration
1000 Years of Temperature Changes
Edgartown, MA - today
Edgartown with 1 m sea level rise
Edgartown with 1 m sea level rise and storm surge from Cat. 2 hurricane
Every Year an Average Coal Plant Releases 3,700,000 tons of CO2 10,000 tons of SO tons of particulates 10,200 tons NOx 720 tons of CO 220 tons of volatile organic compounds (VOC) 170 pounds of mercury 225 pounds of arsenic 114 pounds of lead And there are over 600 of them in the US. Source: Union of Concerned Scientists:
Types of Pollutants CO 2 – Global Warming CO – Health problem PM – Respiratory and heart disease, haze SOx – Acid Rain, respiratory illness, haze NOx – Ozone formation, acid rain, smog, nutrient loading, global warming Mercury – Neurotoxin Lead – Neurotoxin Arsenic - Poison VOCs – Numerous health problems Ozone – Health problems, damage to flora & fauna Hundreds of other toxic chemicals