Project Background
In the current global context where the promotion of renewable energy is actively underway, Europe, with its high – level emphasis on clean energy and supportive policies, has become a frontier for solar energy applications. With the continuous increase in energy costs and the pursuit of energy independence and sustainability, more and more European users are paying attention to and adopting solar energy systems.
About this 20kW Solar System with Battery Storage, a user named Mr. Müller from Germany came across our official website www.maxbo-solar.com of Maxbo Solar. He was attracted by our rich range of solar products and professional solutions. Mr. Müller lives in a small town in southern Germany. He owns a detached house and a small home – based workshop. Due to the relatively high local electricity costs and his desire to reduce dependence on the traditional power grid, achieve energy self – sufficiency, and contribute to environmental protection, he contacted us through the website’s contact form, hoping that we could design a solar energy system suitable for his electricity needs.
Analysis of User’s Electricity Demand
After detailed communication with Mr. Müller, we learned about his electrical equipment and approximate daily electricity consumption as shown in the following table:
| Electrical Equipment | Power (W) | Daily Usage Duration (h) | Daily Power Consumption (kWh) |
|---|---|---|---|
| Home Lighting | 300 | 5 | 1.5 |
| Refrigerator | 200 | 24 | 4.8 |
| Television | 150 | 3 | 0.45 |
| Computer | 200 | 4 | 0.8 |
| Washing Machine | 1000 | 2 | 2 |
| Home – based Workshop Equipment | 3000 | 6 | 18 |
| Total | 27.55 |
In addition, Mr. Müller hopes that in case of extreme weather or long – term cloudy days, the system can ensure at least 3 days of basic electricity supply.
Maxbo Solar’s Solution
Based on Mr. Müller’s electricity demand and the local sunshine conditions (the average sunshine duration in southern Germany is about 4 hours per day), we recommended an off – grid 20kW solar energy system with battery energy storage for him. The following is the detailed configuration of the system:
| Component Name | Specification | Quantity | Detailed Parameters |
|---|---|---|---|
| Solar Panel | 550W | 36 pieces | Weight: 28kg; Size: 2279x1134x35mm; 12 – year product warranty, 25 – year linear power warranty |
| Hybrid Inverter | 11kW | 2 units | Battery voltage: 48V; Rated output power: 11kW; Rated output voltage: 220/230/240VAC; MPPT tracking voltage: 90 – 500V; Maximum PV input voltage: 500V; Size: 500571148mm; Certification: CE |
| Lithium – ion Battery | 48V 200Ah | 2 pieces | Grade A cells; Cycle life: 5000 – 6000 times at 80% depth of discharge (DOD); Size: 465682246mm; Weight: 88kg; Warranty: 6 years |
| Aluminum Alloy Bracket | Suitable for 36 panels | 1 set | Roof/ground installation system; Free design display |
| Cable and Connector | 4 rolls (100m/roll, 4mm²), including 18 MC4 plugs | 1 set | Certification: TUV, CE, IEC |
| Panel Wooden Packaging | Custom – made | 1 set |
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System Power Generation Calculation
The 36 550W solar panels equipped in this system have a total power of 19.8kW (36×550W = 19800W = 19.8kW). Under the condition of an average sunshine duration of 4 hours per day in southern Germany, the theoretical daily power generation is: 19.8kW×4h = 79.2kWh. Considering the system efficiency (the efficiency of a general off – grid solar energy system is about 95%), the actual daily power generation is approximately: 79.2kWh×95% = 75.24kWh, which is in line with the 76kWh in the configuration list (within a certain error range).
Battery Energy Storage Calculation
The capacity of each lithium – ion battery is 48V×200Ah = 9.6kWh, and the total energy storage of two lithium – ion batteries is 19.2kWh. According to Mr. Müller’s daily electricity consumption of 27.55kWh, relying only on battery energy storage, it can meet the electricity demand for about 19.2kWh÷27.55kWh ≈ 0.7 days. However, combined with the daily power generation of the solar panels, under normal sunshine conditions, the battery can be continuously charged and meet the daily electricity demand. At the same time, in order to meet Mr. Müller’s requirement of 3 – day basic electricity supply in extreme weather, the number of batteries can be considered for increase according to the actual situation.
System Cost
| Component Name | Unit Price (US$) | Quantity | Total Price (US$) |
|---|---|---|---|
| Solar Panel – 550W | 49.50 | 36 | 1,782.00 |
| Inverter – 11kW | 450.00 | 2 | 900.00 |
| Lithium – ion Battery | 985.00 | 2 | 1,970.00 |
| Aluminum Alloy Bracket | 1,120.00 | 1 | 1,120.00 |
| Cable and Connector | 340.00 | 1 | 340.00 |
| Panel Wooden Packaging | 100.00 | 1 | 0.00 (Free) |
| Total | – | – | 6,112.00 |
The above price is the FOB (Free on Board) China Price.
Advantages of Maxbo Solar Products
As a professional solar product supplier, Maxbo Solar has been committed to providing high – quality and high – performance solar energy solutions for global users. Our products have the following significant advantages:
Solar Panels
- High – efficiency Power Generation: Adopting advanced photovoltaic technology, the high power output of 550W can obtain more solar energy within a limited installation area and improve the power generation efficiency.
- Long – life Guarantee: A 12 – year product warranty and a 25 – year linear power warranty ensure the stability and reliability of solar panels during long – term use.
- Quality Certification: Passed a number of international authoritative certifications, such as TUV, CE, etc., and meet strict quality and safety standards.
Inverters
- Intelligent Control: Equipped with advanced MPPT (Maximum Power Point Tracking) technology, it can track the maximum power output of solar panels in real – time and improve the overall system efficiency.
- Stable Output: It can provide stable 220/230/240VAC alternating – current output to meet the needs of different electrical equipment.
- Reliable Performance: After strict testing and verification, it has good anti – interference ability and stability to ensure normal operation in various complex environments.
Lithium – ion Batteries
- High Energy Density: Using Grade A cells, it has a high energy density and can store more electrical energy in a relatively small volume.
- Long Cycle Life: It can reach 5000 – 6000 cycles at 80% depth of discharge (DOD), greatly reducing the battery replacement cost.
- Safe and Reliable: Equipped with a complete Battery Management System (BMS), it has multiple protection functions such as over – charge, over – discharge, over – current, and short – circuit to ensure the safe use of the battery.
| Panel Type | Efficiency | Cost per Watt (EUR) | Lifespan | Best for |
|---|---|---|---|---|
| Monocrystalline | 18%-22% | €0.80 – €1.00 | 25+ years | Small roofs, high efficiency |
| Polycrystalline | 15%-18% | €0.60 – €0.80 | 20 – 25 years | Large roofs, budget-friendly |
| Thin-Film | 10%-12% | €0.50 – €0.70 | 15 – 20 years | Curved roofs, flexible design |
Circuit Connection Diagram
Conclusion
Through this 20kW off grid solar energy system with battery energy storage designed for Mr. Müller, it can not only meet his current electricity demand, achieve energy self – sufficiency, and reduce dependence on the traditional power grid, but also save a large amount of electricity costs for him in the long – term use. At the same time, the high – quality products and professional solutions of Maxbo Solar also provide a strong guarantee for the stable operation and reliability of the system.
With the continuous development and popularization of renewable energy technology, solar energy systems will play a more important role in the future energy field. Maxbo Solar will continue to adhere to the concept of innovation, quality, and service, provide high – quality solar energy solutions for more global users, and jointly promote the development and application of clean energy.
Email: [email protected]
References
[1] International Energy Agency. Solar PV Global Market Outlook. [Online]. Available: https://www.iea.org/reports/solar – pv – global – market – outlook.[2] European Solar Industry Federation. Annual Market Report. [Online]. Available: https://www.efsf.org/publications/.
