Energy Harvesting Day 1: Energy Review April 15, 2013 Paul Nickelsberg Orchid Technologies Engineering and Consulting, Inc. www.orchid-tech.com Energy Harvesting Review Energy harvesting is the process of capturing trace amounts of naturally occurring energy from various sources. Accumulating the Energy Storing the Energy Applying the Energy for Useful Purpose 2 Measures of Energy SI Units SI System Fundamental Units Unit of Length is the meter (m) Unit of Mass is the kilogram (kg) Unit of Time is the second (s) Also called the MKS (meter/kilogram/second) System

3 Measures of Energy SI Units Base Units Physical Measure Length Unit of Measure Modern Base Unit Definitions Meter Distance light travels in 1/299,792,458 Seconds Mass Kilogram Mass of International Kilogram Time

Second Duration of 9,192,631,770 periods caesium 133 Ampere Electric Current Force in conductors 1m apart Kelvin Temperature Fraction 1/273.16 temperature triple point water Mole Quantity of Matter Elementary particles of 0.012 kg carbon 12 Candela

Light Intensity Raiant intensity of luminous source 4 Measures of Energy SI Units Derived Units of Interest Physical Measure Newton Unit of Measure Modern Derived Unit Definitions Force / Weight Newton (kg m/s) Joule Energy / Work / Heat

Newton meter (kg m/s) Watt Power Joules per second (kg m/s) Coulomb Electric Charge Second Amps (s A) Volt Electromotive Force Watt per Amps (W / A) Ohm Electrical Resistance

Volts per Amps (V / A) Farad Electrical Capacitance Charge per Volt (C / V) Weber Magnetic Flux Volt Second (V s) Henry Electrical Inductance Weber per Amp (Wb / A) 5 Measures of Energy SI Units Scaling Prefixes Name

Factor Name Factor hecto- (h) 10 centi- (c) 10 kilo- (k) 10 mili- (m) 10 mega- (M)

10 micro- () 10 giga- (G) 10 nano- (n) 10 tera- (T) 10 pico- (p) 10 penta- (P)

10 femto- (f) 10 exa- (E) 10 atto- (a) 10 zetta- (Z) 10 zepto- (z) 10 yotta- (Y)

10 yotta- (y) 10 6 Units of Measure SI Units Force - Newton Work / Energy - Newton-meter (Joule) Power - Joule per second (Watt) 7 (kg m/s) (kg m/s) (kg m/s) Units of Measure SI Units

Mechanical Force F = ma mass in kilograms acceleration in meters/sec A 1kg apple (big apple) accelerates at 9.882 m/s hitting the head with 9.882 nm of force. 8 Measures of Energy SI Units Mechanical Work Work is the amount of energy transferred to a system by the action of force acting along a finite distance Car pulled down level street by three people each exerting 2100N of force directly on the back of the car for 125 meters before they got tired did: Human heart moves a cylinder of blood in a 4cm diameter aorta. Force is 0.2N, distance is 0.0557m, per beat the heart

does: (2100N * 3) * 150m = 9.45 x 10 Joules 0.2N * 0.0557m = 0.0111 Joules 9 Units of Measure SI Units Mechanical Power Power is the time-rate at which a certain amount of work is performed. The energy to move the car 150m was 9.45 x 10 Joules. If it took them two and a half minutes to move the car, the power expended was: If the heart beats 72 times per minute and we average the energy per beat to find the power in watts generated by the heart we find: 9.45 x 10j / 150s = 630 Watts

630 / 746 = 0.84 Hp 0.0111j * 72 = 0.802 joules / minute 0.802 / 60 = 0.013 Watts (13mW) 10 Units of Measure SI Units Other Interesting Units Kilowatt-hour measure of energy - A measure of energy - Thousands of Watts * Hours - 3,600,000 joules = 1.0 kWh Horsepower measure of power - 1Hp = 746 Watts 11 Units of Measure SI Units Unit Conversions To Convert From To

Multiply By BTU (Energy) Joule 1.05 x 10 Calorie (Energy) Joule 4.18 x 10 Electronvolt (Energy) Joule 1.60 x 10 Foot-pound Joule

1.35 x 10 Kilowatt Hour Joule 3.60 x 10 See The International System of Units (SI) catalogue of Measures for other very helpful conversion formulas. 12 Energy Harvesting Review Energy harvesting is the process of capturing trace amounts of naturally occurring energy from various sources. Energy is that which we pay in order to get things done. Power is the rate at which we make payment of energy in order to get things done. 13

Energy Harvesting Review Energy harvesting is the clever identification of potential sources of energy, and the collection, transformation and storage of that energy for application to a particular purpose. Clever identification: Collection: Transformation: Storage: Purpose: Sun Light Solar Cell Solar Cell Battery Save Gas 14

Energy Harvesting Review Energy harvesting is the clever identification of potential sources of energy, and the collection, transformation and storage of that energy for application to a particular purpose. Specs: Wingspan 63.4m, Solar Cell Area: 200m, Weight 1,600 kg, Motors: 4 x 7.5kW (10Hp) Each, Cruise Speed 70 km/h 15 Energy Harvesting Review Energy harvesting is the clever identification of potential sources of energy, and the collection, transformation and storage of that energy for application to a particular purpose. F = * r * S * C * V R = air pressure

S = Surface Area C = Lift V = Wind Speed Energy = F * Distance This is a momentum equation 16 Energy Harvesting Review Energy harvesting is the clever identification of potential sources of energy, and the collection, transformation and storage of that energy for application to a particular purpose. Jaeger-LeCoultre Atmos Clock Temperature and pressure variation winds main spring 17

Energy Harvesting Review Energy harvesting is the clever identification of potential sources of energy, and the collection, transformation and storage of that energy for application to a particular purpose. Self-winding watch mechanism ETA 2824 Normal arm motion winds the main spring 18 Energy Harvesting Sources

Photo Electrical Light Magnetic Inductive Motion / Vibration Radiated Energy RF Sources Piezoelectric Vibration Thermal Heat Chemical - Batteries 19 Energy Harvesting Sources The World of Energy Sources RF Energy Vibration Energy Thermal Energy

Photovolatic Energy Density 0.1 W/cm Density 1 mW/cm Density 10 mW/cm Density 100 mW/cm 20 20 Energy Harvesting Review Step 1: Identify Energy Needs a) Operate valve motor twice daily b) Operate Ignition once daily Step 2: Match Energy Source

c) Polycrystalline Solar Cell d) Lithium Ion Battery Step 3: Implement Device e) Select Motor / Valves f) Select Igniter g) Select Control Microprocessor h) Select Monitor Sensors Step 4: Consider Failure Modes 21 Energy Harvesting Review Come back tomorrow 22