How Solar Power Works

There are only 4 parts to a Solar Power System: Panel , Charge Controller, Battery, and DC to AC inverter for 120 / 240 Volt Power. Larger systems can easily be done by adding panels and controllers - there is no limit to how many. This maximizes system performance because each panel / controller combination is optimized to its own maximum power point. A single point of failure does not take the whole system off line as in traditional high voltage systems with a large controller - this increases system performance and reliability.
Connecting up a solar power system is easy - there are only 2 wires between each component. One Positive (+) usually RED and one Negative (-) usually Black for all DC sections up to the DC to AC inverter which converts the DC power into household AC Power of 120 or 240 volts, 50 or 60 cycles per second dependaning on where in the world you are. A small system may have one or 2 Solar panels, one MPPT Charge Controller, one Battery, and optinally an Inverter if AC power is desired. Larger systems just add more "Solar Circuits" feeding a larger Battery Bank so its just repeating the wiring for each circuit - 2 wire in and 2 wires out. A sample wiring diagram with 3 controllers is below which uses a Household AC breaker box for DC Power.
The wiring on the DC mains is sized for the system load - use the Electrical codes for minimum sizing though bigger is better with low voltage DC wiring. The above example is good for 1800 watts on 12 volts and 3600 watts on 24 volts. A standard 100 Amp Breaker Box is good for 200 amps because BOTH main lugs are used to carry the (+) wire current. Square D Homeline breakers are rated for DC use in the Solar Electrical Code - any non magnetic breaker will work on DC. Keep DC wires as short as possible to the battery and DC to AC inverter to minimize power loss / voltage drop under load. Controller to Breaker Box should be #12 size (20 amps) and between 3 and 5 feet long... a little resistance here is desireable to minimize ripple currents.
At the heart of our Solar Charge Controller is a very efficient DC-DC Power converter which transfers nearly all of the solar panels energy to the system over a very wide power range. The Charge Controller is the "Brain" and the most important part of the Solar Power System. Our 20 Amp Buck Boost Controller "Sol" takes this further with higher measured efficiency over 99.2% peak and the ability to boost Panel voltage up to Battery voltage when the operating point drops due to extreme shading or low light. Sol can extract power where other controllers are not able to due to the Buck Boost power conversion.
The Ra Version 2 model is a 50 Watt, 3.5 Amp Charge Controller is also a Buck-Boost MPPT and has 35 Volt Maximum and 10 volt minimum Solar Voltage with over 96% peak efficiency. Output is for 12 volts only. It comes in a small 3D Printed plastic box and weighs under 3 ounces. Ra is perfect for portable and lower power applications.
All models have our customized dual mode Maximum Power Tracking routine "MPPT" which adjusts the power transfer about 6000 times per second to yield maximum performance even in partial shading of the Solar Panels. Cloudy days produce power too - Our Charge Controllers get every last watt possible from the panel at all times. The result is up to 2.16 times the Power that a PWM charge controller would deliver with a given solar panel configuration. See our Product Comparison on the Home Page.
* PWM Charge Controllers don't do Power Conversion as they lack an efficient DC-DC converter. Thus they waste a lot of available power that goes unused or turned into heat. PWM stands for Pulse width modulation which basically connects Panel To Battery directly with varying duty cycle on and off - When they are in the off portion of the cycle 0% power is transferred * HEAT = LOST POWER so beware of controllers with large heatsink fins claiming high eficiency. Also HEAT = SHORTER LIFE of the internal components.
Low RFI performance is accomplished by careful design and PCB layout to achieve performance that is unmatched in the solar industry. Our Spread Spectrum Modulation further reduces the already quiet controller by another 12-20 dB and is optimized for Narrowband Communications such as AM, SSB, and CW.
When the Sun rises in the morning the Solar Charge Controller switches from NIGHT mode to DAY mode and transfers the previous day’s totals to memory. The Power Stage is turned on and Solar energy begins to charge the system battery. The LCD display cycles through the daytime parameters… Battery Voltage, Panel Voltage, Amps output, Power Output, Peak Power, Amp Hours, and Internal Board Temperature. When the battery is full the charger shuts off and the LCD displays "bat" "Full" along with the amount of amp hours it took to reach full. The controller will stay in a standby mode until the battery voltage starts to drop - then charging will start again as long as solar power is present.
After Sunset when the panel voltage drops the Power Stage is turned off and the LCD Display switches to NIGHT mode.
The LCD Display cycles through the Battery Voltage, All time Maximum Power, and the last 7 Days Amp Hour Totals.
Our products are designed for many years of reliable operation using components rated for 125°C operation which is about 60°C ABOVE the highest operating temperature under normal conditions. The Controllers are protected from reverse battery, input short circuit, reverse power flow, over current, over temperature, and reversed Solar Panel connections.
Connecting up a solar power system is easy - there are only 2 wires between each component. One Positive (+) usually RED and one Negative (-) usually Black for all DC sections up to the DC to AC inverter which converts the DC power into household AC Power of 120 or 240 volts, 50 or 60 cycles per second dependaning on where in the world you are. A small system may have one or 2 Solar panels, one MPPT Charge Controller, one Battery, and optinally an Inverter if AC power is desired. Larger systems just add more "Solar Circuits" feeding a larger Battery Bank so its just repeating the wiring for each circuit - 2 wire in and 2 wires out. A sample wiring diagram with 3 controllers is below which uses a Household AC breaker box for DC Power.
The wiring on the DC mains is sized for the system load - use the Electrical codes for minimum sizing though bigger is better with low voltage DC wiring. The above example is good for 1800 watts on 12 volts and 3600 watts on 24 volts. A standard 100 Amp Breaker Box is good for 200 amps because BOTH main lugs are used to carry the (+) wire current. Square D Homeline breakers are rated for DC use in the Solar Electrical Code - any non magnetic breaker will work on DC. Keep DC wires as short as possible to the battery and DC to AC inverter to minimize power loss / voltage drop under load. Controller to Breaker Box should be #12 size (20 amps) and between 3 and 5 feet long... a little resistance here is desireable to minimize ripple currents.
At the heart of our Solar Charge Controller is a very efficient DC-DC Power converter which transfers nearly all of the solar panels energy to the system over a very wide power range. The Charge Controller is the "Brain" and the most important part of the Solar Power System. Our 20 Amp Buck Boost Controller "Sol" takes this further with higher measured efficiency over 99.2% peak and the ability to boost Panel voltage up to Battery voltage when the operating point drops due to extreme shading or low light. Sol can extract power where other controllers are not able to due to the Buck Boost power conversion.
The Ra Version 2 model is a 50 Watt, 3.5 Amp Charge Controller is also a Buck-Boost MPPT and has 35 Volt Maximum and 10 volt minimum Solar Voltage with over 96% peak efficiency. Output is for 12 volts only. It comes in a small 3D Printed plastic box and weighs under 3 ounces. Ra is perfect for portable and lower power applications.
All models have our customized dual mode Maximum Power Tracking routine "MPPT" which adjusts the power transfer about 6000 times per second to yield maximum performance even in partial shading of the Solar Panels. Cloudy days produce power too - Our Charge Controllers get every last watt possible from the panel at all times. The result is up to 2.16 times the Power that a PWM charge controller would deliver with a given solar panel configuration. See our Product Comparison on the Home Page.
* PWM Charge Controllers don't do Power Conversion as they lack an efficient DC-DC converter. Thus they waste a lot of available power that goes unused or turned into heat. PWM stands for Pulse width modulation which basically connects Panel To Battery directly with varying duty cycle on and off - When they are in the off portion of the cycle 0% power is transferred * HEAT = LOST POWER so beware of controllers with large heatsink fins claiming high eficiency. Also HEAT = SHORTER LIFE of the internal components.
Low RFI performance is accomplished by careful design and PCB layout to achieve performance that is unmatched in the solar industry. Our Spread Spectrum Modulation further reduces the already quiet controller by another 12-20 dB and is optimized for Narrowband Communications such as AM, SSB, and CW.
When the Sun rises in the morning the Solar Charge Controller switches from NIGHT mode to DAY mode and transfers the previous day’s totals to memory. The Power Stage is turned on and Solar energy begins to charge the system battery. The LCD display cycles through the daytime parameters… Battery Voltage, Panel Voltage, Amps output, Power Output, Peak Power, Amp Hours, and Internal Board Temperature. When the battery is full the charger shuts off and the LCD displays "bat" "Full" along with the amount of amp hours it took to reach full. The controller will stay in a standby mode until the battery voltage starts to drop - then charging will start again as long as solar power is present.
After Sunset when the panel voltage drops the Power Stage is turned off and the LCD Display switches to NIGHT mode.
The LCD Display cycles through the Battery Voltage, All time Maximum Power, and the last 7 Days Amp Hour Totals.
Our products are designed for many years of reliable operation using components rated for 125°C operation which is about 60°C ABOVE the highest operating temperature under normal conditions. The Controllers are protected from reverse battery, input short circuit, reverse power flow, over current, over temperature, and reversed Solar Panel connections.
Contact us at: DIYSolarForU@gmail.com