1. Overview of Off-grid PV Factory System

In off-grid areas and unstable power supply areas, industrialization is often restricted by energy supply. PV power generation technology is widely used in off-grid areas and unstable power supply areas due to its stable generation efficiency, long service life, small geographical limitations and high technology maturity. Construction of off-grid power stations combining PV and energy storage has gradually become a priority for factory owners to supply power to manufacturing units.

(1) Off-grid PV Factory Power Generation Schematic Diagram

(2) Off-grid PV System Load Type

① Ground

Idle land near the buildings of some factories can be used as the installation point of off-grid PV system. When installing, it should be avoided the shadow of nearby buildings. The installation on the ground usually adopts the inclined bracket array installation, and the bracket foundation generally includes cement counterweight, prefabricated cement counterweight, ground pile foundation, etc., which shall be selected reasonably according to the land structure of the project site.

② Concrete Roof

The concrete roof is generally horizontal or has 2 ~3° inclination angle. The roof has waterproof protection measures, there are around high meters parapet. Part of the roof has ventilation ducts and other facilities. According to the different structural characteristics of the concrete roof, the PV support foundation generally has cement counterweight, precast cement counterweight, chemical anchorage and so on.

③ Color Steel Tile Roof

Color steel tile roof is generally herringbone, high in the middle, low at both ends, forming a different angle of the slope roof. There are also parts of the roof that have a tilt. The common overall structure of the building is steel structure, concrete, brick body wall, etc. Color steel tile roof installation is simple, the most common color steel tile structure has vertical locking type, angle tooth type, ladder type. For the vertical locking edge type and angle tooth type color steel tile roof, the use of color steel tile crest, using special aluminum fixture fixed bracket guide rail.

(3) Off-grid PV Power Generation System Composition

Off-grid PV factory power generation system is mainly composed of solar array, off-grid PV inverter, battery bank, control cabinet, support and other equipment. It can be customized according to users' actual load conditions and energy access mode, so as to realize power grid, oil generator and other energy access, forming a variety of energy hybrid power supply system.

The system is mainly applied to manufacturing enterprises in areas with no power, unstable power and high electricity price. Use the roof or the ground to install the power generation system, realize the optical storage and supply of electricity or a variety of energy hybrid power supply, to meet the long-term power demand of the plant production equipment.

2. Advantages of Off-grid PV Factory System

(1) Meeting the needs of enterprises to ensure a continuous and stable power supply.

(2) Being obtained long-term power generation benefits and reducing the power cost of factories in areas with high electricity prices.

(3) One-time investment, short payback period, enjoying more than 25 years of stable returns.

(4) Using idle roof or land for construction, do not occupy production land resources, activate idle assets.

(5) With heat insulation effect, it can effectively reduce the internal temperature of the plant so as to save cooling input.

3. Examples of Off-grid PV Factory System

(1) Off-grid PV Factory System in Kano State, Nigeria

The project is located in Sharada Industrial Park, Kano State, Nigeria (latitude 8.5° N, longitude 12.0° E). The local power grid is very unstable, the factory has a large electrical load, and the owner often use diesel generators to generate electricity. The power consumption period of the owner is only concentrated in the daytime, and there is no need to be equipped with energy storage battery. The pure off-grid self-use system is adopted. The project adopts a color steel tile roof facing south, and is equipped with a PV power generation system, totaling 527KW. EPC costs about $395,000.

The area is in a savanna climate with abundant light. The annual effective sunshine hours are about 1539kwh /kWp/year. The local electricity price is $0.115/kWh. Considering the annual attenuation of PV power generation and the proportion of 100% self-use, the payback period of investment is about 42 months.

In this project, diesel generator is used as the main power source when PV power cannot be generated normally in rainy days. If energy storage batteries are added, PV energy storage power generation system can be formed to completely replace diesel generators and continuously reduce energy consumption cost.

 Our company is committed to the research of new energy scenarios. Boyang has an independent solution design team and standardized solutions in various scenarios. At the same time, we can provide customers with better prices and more reliable new energy power supply solutions.