PV systems with storage

Solar system with storage for maximum energy independence

A solar power system with storage allows you to effectively use self-generated energy around the clock. While conventional PV systems without battery storage feed excess electricity into the public grid, a photovoltaic system with storage stores the energy not immediately used for later self-consumption. This approach significantly increases your energy independence and reduces your reliance on external electricity providers. At PVundSO, you'll find complete solutions with storage capacities ranging from 4,8 kWh to 20,48 kWh, catering to various household sizes.

Integrating a battery storage system into your solar power system increases self-consumption from an average of 30% for grid-tied systems to up to 70%. A 10 kW PV system with battery storage generates approximately 9.500 to 10.500 kWh annually in Germany, depending on location and orientation. With a 10,24 kWh battery, you can cover a significant portion of the electricity needs of a typical four-person household. The bifacial solar modules in our systems utilize both direct and reflected sunlight, resulting in up to 15% higher energy yields than conventional modules.

Choosing the right system size depends on several factors. Your available roof area, annual electricity consumption, and budget determine the optimal configuration. Sound sizing prevents both undersupply and unnecessary overcapacity, maximizing the return on your investment.

household size	Annual consumption	Recommended system output	Storage capacity	Required roof area
1 to 2 persons	2.500 to 3.500 kWh	5 to 6 kW	4,8 to 5,12 kWh	25 to 30 m²
3 to 4 persons	4.000 to 5.500 kWh	8 to 10 kW	10,24 kWh	45 to 55 m²
5 to 6 persons	6.000 to 8.000 kWh	15 kW	15,36 kWh	75 to 85 m²
Large household	from 8.500 kWh	20 kW	20,48 kWh	95 to 110 m²

The table shows typical configurations for different household sizes. For a four-person household with an annual consumption of 5.000 kWh, a 10 kW system with a 10,24 kWh storage capacity covers approximately 65 to 70% of the demand with self-generated electricity. The bifacial modules require approximately 50 m² of roof area with optimal south-facing orientation. Different orientations or shading necessitate a corresponding adjustment of the module area.

Reduce the long-term costs of a PV system with storage

The costs of a PV system with storage are recouped more quickly than for systems without energy storage due to a combination of several factors. The current average electricity price of €0,40 per kWh makes self-generation particularly attractive. A 10 kW PV system with battery storage generates electricity at production costs of approximately €0,08 to €0,11 per kWh. With an annual self-consumption of 7.000 kWh, this translates to savings of over €2.000 in electricity costs per year.

The amortization period for a complete photovoltaic system package with storage is between 7 and 10 years, while grid-tied systems require 11 to 14 years. This difference results from the significantly higher self-consumption and the lower dependence on low feed-in tariffs. Current subsidies from the KfW bank further reduce the initial investment by up to €10.200 with low-interest loans. Some German states offer grants of €200 to €400 per kWh of storage capacity, which further improves profitability.

Switching to a complete solar system with storage protects you against rising energy prices in the long term. While electricity costs have increased by an average of 4,2% annually over the last ten years, your production costs remain virtually constant over the entire lifespan of 25 to 30 years. Maintenance costs for a complete PV system with storage are limited to occasional cleaning and a possible battery replacement after 12 to 15 years. The bifacial modules have a 30-year performance guarantee with a maximum degradation of 15%, ensuring long-term planning security.

Photovoltaic system with storage as a reliable emergency power supply

A photovoltaic system with storage functions as an independent emergency power supply during grid outages, ensuring the power supply to critical appliances. The hybrid inverters in our systems detect grid interruptions within milliseconds and automatically switch to island mode. This ensures that refrigerators, heating controls, internet routers, and lighting remain functional even during power outages lasting several hours. A 10,24 kWh storage system can supply a two-person household with energy for up to 36 hours with reduced consumption before the solar panels recharge during daylight hours.

The emergency power function of your solar system with storage complete package can be individually configured. You define which circuits are prioritized in the event of a power outage and what minimum charge the battery storage should maintain for emergencies. Reserves of 20 to 30% of the total capacity are typical, which corresponds to approximately 3 to 4,5 kWh for a 15,36 kWh system. This reserve is sufficient to support an average household with basic power overnight, while the solar panels recharge the storage the following day.

The practical emergency power capacity depends on consumption patterns. Critical appliances such as refrigerators, freezers, and heating controls require a continuous power consumption of between 200 and 400 watts. In addition, there are occasional peak loads from lights, kettles, or laptops.

Memory size	Available energy (80% discharge)	Power supply duration at 500W	Power supply duration at 1.000W	Suitable for
4,8 kWh	3,84 kWh	7,5h	3,8h	Basic care for 1 to 2 people
5,12 kWh	4,1 kWh	8h	4h	Basic services for small households
10,24 kWh	8,2 kWh	16h	8h	Full board for 2 to 3 people
15,36 kWh	12,3 kWh	24h	12h	Full board for 4 to 5 people
20,48 kWh	16,4 kWh	32h	16h	Large households several days

These figures take into account a depth of discharge of 80%, which is optimal for lithium batteries. With a reduced power consumption of 500 watts, a 10,24 kWh storage system is sufficient for 16 hours of emergency power, covering a night and the morning until recharging by the solar panels. Larger storage systems, starting at 15,36 kWh, enable several days of self-sufficiency, especially if daytime solar radiation assists with recharging. These capacities make the best photovoltaic system with storage a reliable safeguard against power outages.

Use solar power with storage even at night

Solar power with storage bridges the gap between generation and consumption in private households. While solar panels reach their peak output between 10 a.m. and 16 p.m., the main consumption occurs in the morning and evening hours, between 6 and 9 a.m. and 18 and 22 p.m. A complete PV system with storage stores the surplus energy generated at midday and makes it available in the evening when the family is cooking, watching television, and using electronic devices. This increases self-consumption from 30% without storage to 60 to 70% with a battery system.

The discharge strategy of your solar power system with storage can be controlled via the energy management system. Intelligent algorithms optimize charging and discharging based on weather forecasts, historical consumption data, and current electricity prices. If mostly cloudy days are expected, the system maintains a larger reserve in the storage unit, while a deeper discharge occurs if the forecast is favorable. The Sofar hybrid inverters communicate with the storage unit and dynamically adjust the charging and discharging currents between 0,5 and 5 kW to maximize battery lifespan.

Nighttime use of solar power with storage reduces grid consumption to a minimum. A 5,12 kWh storage system completely covers the nighttime base load of 3 to 4 kWh when fully charged in the evening. Larger systems with 10,24 kWh or 15,36 kWh additionally allow for morning use before sunrise and create a buffer for cloudy days. The lithium iron phosphate batteries in our systems can withstand over 6.000 charge cycles at 80% depth of discharge, which corresponds to a lifespan of 15 to 18 years with daily use. The efficiency of the storage system is between 94 and 96%, resulting in minimal conversion losses.

Complete PV system with storage including all components

A complete PV system with storage from PVundSO includes all components for immediate, operational installation. The package comprises bifacial solar modules with a power output of 410 to 430 watts, a Sofar hybrid inverter, modular lithium battery storage, a mounting system, DC cabling, and connection materials. The bifacial modules utilize sunlight on both sides and achieve up to 25% higher yields compared to monofacial modules on bright roof surfaces or in snowy conditions. All components are perfectly matched and comply with VDE standards for photovoltaic systems.

The hybrid inverter is the heart of your photovoltaic system with energy storage and controls all energy flows within the system. It converts the direct current (DC) from the modules into 230 V alternating current (AC), charges the battery storage, and feeds surplus power into the grid. The devices feature two to three MPPT trackers that independently optimize for different roof orientations. With an east-west orientation, this maximizes daily yield over a longer period. The inverters have a European efficiency of 97,6% and operate at a noise level below 35 dB, making them suitable for indoor installation.

The modular battery storage systems can be expanded as needed. Each module has a capacity of 5,12 kWh and can be combined with up to three additional units to create a 20,48 kWh system. This allows for gradual adaptation to increasing energy demands, such as the purchase of an electric vehicle or a heat pump. The battery management system continuously monitors the temperature, voltage, and state of charge of each individual cell, ensuring optimal operating conditions. The storage units have an IP65 protection rating and are suitable for installation in basements or garages at temperatures between -10 and +45 degrees Celsius.