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Jeff / KB3SPH (Kilo Bravo Three Sierra Papa Hotel) 24 January 2019. S olar Power F or the Ham. Jeff / KB3SPH (Kilowatt Battery Three Solar Powered Ham) Just for tonight! 24 January 2019. S olar Power F or the Ham. What To Expect! Enhanced Show & Tell for a specific solar power system
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Jeff / KB3SPH (Kilo Bravo Three Sierra Papa Hotel) 24 January 2019 Solar Power For the Ham
Jeff / KB3SPH (Kilowatt Battery Three Solar Powered Ham) Just for tonight! 24 January 2019 Solar Power For the Ham
What To Expect! Enhanced Show & Tell for a specific solar power system Demonstrate/explain basic principles applicable to all solar power systems *Sit back, relax, and enjoy the show!*
Reference: Emergency Power for Radio Communications by Michael Bryce, WB8VGE
SUN • Nearest Star to Earth • Middle-aged yellow star • 4.6 billion years old • Life-span of 10 billion years
SUN, continued Nuclear fusion in the Sun’s core Converts Hydrogen into Helium Massive release of energy Photons eventually released from Sun’s surface
SUN, continued How long does it take photons emitted from the Sun’s surface to reach the Earth? Let’s put our Astronomical/Mathematical thinking caps on and find out!
Distance from the Earth to the Sun What is the term for this distance?
Distance from the Earth to the Sun An Astronomical Unit (AU) How long is one AU in miles?
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles How about kilometers?
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) Let’s simplify using scientific notation
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km)
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km In meters?
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m)
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = cHow fast is it?
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = c c = 186 thousand miles per second How about meters/second (sec)?
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = c c = 186 thousand miles per second c = 3 * 108m/sec
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = c c = 186 thousand miles per second c = 3 * 108m/sec Hence: 1 AU / c = time for photons to reach Earth
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = c c = 186 thousand miles per second = 150 * 109 m__ _ = 150 * 109m * _1 sec__ 3 * 108 m/sec 1 3 * 108 m Solve for seconds c = 3 * 108m/sec Hence: 1 AU / c = time for photons to reach Earth
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = c c = 186 thousand miles per second = 150 * 109 m__ _ = 150 * 109m * _1 sec__ 3 * 108 m/sec 1 3 * 108 m c = 3 * 108m/sec = 50 * 101 sec = 500 sec Convert to minutes Hence: 1 AU / c = time for photons to reach Earth
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = c c = 186 thousand miles per second = 150 * 109 m__ _ = 150 * 109m * _1 sec__ 3 * 108 m/sec 1 3 * 108 m c = 3 * 108m/sec = 50 * 101 sec = 500 sec Hence: 1 AU / c = time for photons to reach Earth Time in minutes = 500 sec___ 60 sec/min Almost there!
Distance from the Earth to the Sun Is One Astronomical Unit (AU) 1 AU = 93 million miles 1 AU = 150 million kilometers (km) 1 AU = 150 * 106 km 1 AU = 150 * 109 meters (m) Speed of Light = c c = 186 thousand miles per second = 150 * 109 m__ _ = 150 * 109m * _1 sec__ 3 * 108 m/sec 1 3 * 108 m c = 3 * 108m/sec = 50 * 101 sec = 500 sec Hence: 1 AU / c = time for photons to reach Earth Time in minutes = 500 sec___ 60 sec/min = 8. min = 8 minutes 20 seconds
SOLAR (PV) PANEL PV stands for Photovoltaic Photo meaning light Voltaic meaning electricity Electricity from light
SOLAR (PV) PANEL, continued Solar Cell: Basic unit of the PV panel Converts light into electricity Photons knock out electrons causing holes in a semiconductor junction
SOLAR (PV) PANEL, continued Collect the loose electrons and voila’, electric current
SOLAR (PV) PANEL, continued Each solar cell produces about one half of a volt (.5 V), regardless of its size To increase current (amps), one needs to increase the size of the cell Current technology limits cell size to an 8 inch diameter
SOLAR (PV) PANEL, continued Collection of cells = module Collection of modules = panel Panels connected together = array Common definition: A string of cells in a frame = solar panel
SOLAR (PV) PANEL, continued Physical characteristics: Waterproof, no moving parts Panels must face Sun, Tilt angle, “No glow, no go” Panels like the cold, do not like shade
SOLAR (PV) PANEL, continued Rating: Rated by Watts Here we have two 50 Watt panels in parallel = 100 Watts at Standard Test Conditions (STC)
PV PANEL JUNCTION BOXES Panel 2 (50 Watts) Panel 1 (50 Watts) Bypass Diode Bypass Diode Panel 1 Connected in Parallel with Panel 2 for 100 Watts
SOLAR (PV) PANEL, continued STC – Standard Test Conditions Insolation = amount of light hitting the surface of the cell STC = 1000 Watts per meter2 insolation at 25° Celsius (77° Fahrenheit)
SOLAR (PV) PANEL, continued STC is also known as One Sun Realistically, considering clouds and temperature, one can only expect 70% of rated power from a PV panel
SOLAR (PV) PANEL, continued Adding additional panels in parallel (via MC4* connectors) = same voltage, increased amps Adding additional panels in series (via MC4 connectors) = increased voltage, same amps *MC stands for manufacturer Multi-Contact; the 4 for the 4mm diameter contact pin
SOLAR (PV) PANEL, continued This panel’s specifications: Open circuit voltage = 21.6 V Short circuit current = 6.17 A It is safe to short circuit a PV panel Maximum power voltage = 18.0 V Maximum power current = 5.71 A Fusing – panel to charge controller = 10 A
Direct Current (DC) Systems Color Codes Black Red Yellow Green = (-) negative = (+) battery positive = (+) PV positive = ground
Wire Gauge and Ampacity For this system, we’re focused on 12 and 10 AWG cable/wire. *American Wire Gauge
CHARGE CONTROLLER Electronic switch used to prevent overcharging a battery Not a regulator; it won’t work without a battery connected Not always needed, e.g. some solar cell phone chargers have panel connected directly to phone
CHARGE CONTROLLER, continued Types of Charge Controllers PWM– Pulse Width Modulation Rapid switching when in float mode MPPC – Maximum Power Point Controller More circuitry, more expensive Used in larger systems Generate RFI (radio frequency interference)
CHARGE CONTROLLER, continued Monitors battery state-of-charge Applies a charging algorithm Vertical orientation recommended Hinged mounting plate incorporated on this model to facilitate vertical positioning
CHARGE CONTROLLER, continued This Controller’s specifications: Not waterproof (some models are) Nominal voltage = 12 VDC Charge current = 30A Max PV input = 25 VDC Self consumption = < 10mA
CHARGE CONTROLLER, continued Controller Operation Connect battery before panels Disconnect panels before battery Select battery type Determines charging parameters Sealed, Gel, or Flooded Charging stages Bulk, Boost, Float, Equalization
CHARGE CONTROLLER, continued Temperature compensation Has built in internal and an optional external sensor for battery Stress relief was required – the bare wires under the screw terminals came loose when subjected to the weight of the cables and the heating/cooling cycle during operation
BATTERY Charged by panels via charge controller Stores charge produced by solar panels Deep Cycle versus Starting battery Deep Cycle – low amps over a long period of time Starting – high amps over a short period of time USE DON’TUSE
BATTERY, continued Rated in Amp Hours – this one is 55 Amp Hours (rated at 20 hours) A 10 gauge (30 Amp) cable is used between the battery and charge controller and is protected with a 30 Amp fuse