Sunlight on photovoltaic modules produces direct current (DC) electricity which is converted to alternating current (AC) by a device called an inverter, and provide home appliances in the buildings or houses.
When the amount of generated PV electric power exceeds home use, surplus electric power can be sold to electric power companies. ( Case is limited to less than 10kW in system volume)
When the capacity of system is more than 10kW, all generated solar power can be sold to electric power companies.
What are the differences between Monocrystalline silicon and Polycrystalline silicon?
Both of them are manufactured by melting, cooling and solidifying soiled silicon, however manufacture process in solidify is different.
Monocrystalline silicon is manufactured with one crystal and polycrystalline silicon is manufactured with many crystals.
Monocrystalline is high purity silicon therefore it is highly efficient and expensive.
Polycrystalline is produced with reused waste silicones in the process of the solar battery production, this is how polycrystalline can be produced at low cost and large quantity.
Will changing the place, direction or angle of th photovoltaic modules alter the efficiency in power generation?
It was determined that efficiency of power generation with facing south side is 100％, east/west is approximately 87%, and north is about 40%.
Facing south side with 20-30 degrees angle is efficient although angle varies by region.
Can I use it during a power outage?
If power supply stops from electric power companies in case of disaster or planned power outage, you can use PV power for emergency.
※ There is limitation of the amount of electric power available and the usage.
※ This is limited to only inverters with self-sustained operation mode.
What is Self-sustained operation?
When electric power supply stops from electric power companie, unless PV battery generates power,you can get electric power from outage plugs of inverters. This is called self-sustained operation.
What is the output limit? What are the rules called "360hours rules" and "conditional rule"?
Electric power companies limit power output from power facilities depending on situation of electric power supply and demand.
Limiting output includes two rules, 360 hours rules, which can limit output up to 360 hours, and conditional rule, which can limit output over 360 hours with no compensation. Rule that applies is depending on area and capacity of power facility.
360 hours rule
When energy from photovoltaic exceeds acceptable amount of electric power company, it requests limiting output of power up to 360 hours within a year without any compensation
Conditional rule
When assigned electric company by Japan have more applicants of connection than acceptable number, it requests limiting output of power for any amount of hours to those power facilities which applied for connection
