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

Electricity Sources New England 2003

1000 years of CO2 Concentration

1000 Years of Temperature Changes

Edgartown 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 SO2.  500 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

Barnstable County Air Quality Source: