Hybrid inverters

A hybrid inverter is a multifunctional device used in solar systems with battery storage. It combines the functions of a conventional inverter with battery management in a single system.

The main tasks of a hybrid inverter are:

1. Convert direct current (DC) into alternating current (AC): The direct current generated by the solar modules cannot be used directly in the home network. The inverter therefore converts it into household alternating current.
2. Storing excess solar power in batteries: If the solar system produces more electricity than is needed in the house, the hybrid inverter can temporarily store this surplus in a battery storage unit.
3. Feeding electricity from batteries into the house grid when needed: If the solar system does not produce enough electricity or does not generate any electricity at all (e.g. at night), the hybrid inverter can use the electricity from the batteries to cover the house's needs.
4. Intelligent control of the energy flow: The hybrid inverter monitors the energy flow between the solar system, battery and house grid and optimizes it so that self-consumption is maximized and grid consumption is minimized.

Additional functions of hybrid inverters can be:

• Emergency power supply: In the event of a power failure, the hybrid inverter can ensure that the house is supplied with electricity from the batteries.
• Control of heating elements: The hybrid inverter can use excess solar power to heat water or to support a heat pump.
• Connection to smart home systems: The hybrid inverter can be integrated into smart home systems to optimize energy consumption and visualize the use of solar power.

Advantages of hybrid inverters:

• Increased self-consumption: By storing solar power, self-consumption can be significantly increased.
• Independence from the power grid: In the event of a power failure, the power supply from the batteries can be ensured.
• Lower electricity costs: By using solar power and reducing the amount of electricity purchased from the grid, electricity costs can be reduced.
• Environmentally friendly: By using solar energy, greenhouse gas emissions are reduced.

Disadvantages of hybrid inverters:

• Higher purchase costs: Hybrid inverters are more expensive than conventional inverters.
• More complex installation: Installing a hybrid inverter is more complex than installing a conventional inverter.
• Maintenance: Hybrid inverters require regular maintenance.

Conclusion:

Hybrid inverters are a clever solution for homeowners who want to expand their solar system with a battery storage system. They offer a number of advantages, such as increased self-consumption, independence from the power grid and lower electricity costs. However, they are also more expensive to purchase and install than conventional inverters.

Increased self-consumption:

• Storage of excess solar power: A hybrid inverter can store the solar power produced by the solar system during the day and not immediately used in a battery storage system for later use. This makes it possible to significantly increase self-consumption of solar power and reduce dependence on the power grid.
• Intelligent control of the energy flow: The hybrid inverter monitors the energy flow between the solar system, battery and home network and optimizes it so that self-consumption is maximized.

Independence from the power grid:

• Emergency power supply: In the event of a power failure, the hybrid inverter can ensure the house's power supply from the batteries. This is particularly important if important devices such as refrigerators, heaters or medical devices need to continue to operate.
• Self-sufficiency: With a sufficiently dimensioned battery storage system, a high degree of independence from the public power grid can be achieved. This can lead to greater energy security and cost savings.

Lower electricity costs:

• Reduced grid consumption: The high level of self-consumption of solar power reduces the need for electricity from the public grid. This leads to lower electricity costs.
• Use of inexpensive solar power: Solar power is significantly cheaper than electricity from the grid. By using solar power you can save money.

Other advantages:

• Environmentally friendly: By using solar energy, greenhouse gas emissions are reduced and the environment is protected.
• Flexibility: Hybrid inverters offer more flexibility when using solar power. The electricity can also be used, for example, to operate a heat pump or an electric car.
• Future-proof: Hybrid inverters are future-proof and can be integrated into smart home systems.

Disadvantages of hybrid inverters:

• Higher acquisition costs: Hybrid inverters are more expensive to purchase than conventional inverters.
• More complex installation: Installing a hybrid inverter is more complex and requires specialist knowledge.
• Maintenance: Hybrid inverters require regular maintenance.

Conclusion:

Hybrid inverters offer a number of advantages over conventional inverters, which are both economically and ecologically relevant. In particular, the possibility of increasing self-consumption of solar power and increasing independence from the power grid makes hybrid inverters an attractive investment for homeowners with solar systems. However, the higher purchase costs and more complex installation should be taken into account when making the decision.

Hybrid inverters can be categorized according to various criteria:

1. Number of phases:

• Single-phase hybrid inverters: These devices are designed for households with a single-phase power grid. They have limited power and are therefore suitable for smaller solar systems.
• Three-phase hybrid inverters: These devices are designed for households with a three-phase power grid. They have higher power and are therefore suitable for larger solar systems and commercial operations.

2. Structure:

• Stand-alone hybrid inverters: These devices are stand-alone devices that can be installed separately from a battery storage system. They offer more flexibility in the choice of battery storage.
• Integrated hybrid inverters: These devices already contain the battery storage in the housing. They are more compact and easier to install, but usually offer less flexibility in the choice of battery storage.

3. Functions:

• Standard hybrid inverters: These devices offer the basic functions of a hybrid inverter, i.e. converting direct current into alternating current, storing excess solar power in a battery storage unit and feeding power from the battery storage unit into the home network.
• Advanced hybrid inverters: These devices offer additional functions, such as emergency power supply, control of heating elements or connection to smart home systems.

4. Manufacturers:

There are a variety of manufacturers of hybrid inverters. The best-known manufacturers include Solis, Solax, SMA, Fronius, SolarEdge, Kostal and Victron Energy.

When choosing a hybrid inverter, the following factors should be taken into account:

• Power: The required power of the hybrid inverter depends on the size of the solar system and the power requirements of the house.
• Number of phases: The number of phases of the hybrid inverter must match the number of phases of the power grid.
• Design: Stand-alone hybrid inverters offer more flexibility, integrated hybrid inverters are easier to install.
• Functions: Standard hybrid inverters offer the basic functions, advanced hybrid inverters offer additional functions.
• Manufacturers: Various manufacturers offer different quality standards and guarantees.

It is advisable to seek advice from a specialist before purchasing a hybrid inverter in order to make the right choice for your individual needs.

In addition to a hybrid inverter, other components are required for a solar system with battery storage:

1. Solar modules: The solar modules convert sunlight into direct current. The power and number of solar modules depend on the size of the solar system and the power requirements of the house.

2. Mounting system: The mounting system is used to attach the solar modules to the roof or facade of the house.

3. Cables and plugs: Cables and plugs are required to connect the solar modules to the hybrid inverter.

4. Battery storage: The battery storage stores the excess solar power generated during the day for later use. The size of the battery storage depends on the desired level of self-consumption.

5. Protection devices: Protection devices such as overvoltage protection and short-circuit protection protect the solar system from electrical damage.

6. Monitoring system: A monitoring system enables the performance of the solar system and the battery storage to be monitored.

7. Emergency power supply (optional): If an emergency power supply is desired, an additional device is required that distributes the power from the battery storage to the required devices in the house in the event of a power failure.

Component recommendation:

The choice of the right components depends on various factors, such as the size of the solar system, the power requirements of the house, the budget and individual needs. It is advisable to seek advice from a specialist in order to find the right components for your individual solar system.

Additional information:

• It is important that all components of the solar system are compatible with each other.
• The solar system should be installed by a qualified electrician.
• The solar system may be eligible for funding from KfW or other institutions.

With the right planning and selection of components, a solar system with battery storage can be a worthwhile investment that leads to a significant reduction in electricity costs and a higher level of self-consumption of solar power.

Self-consumption optimization is a strategy that maximizes the self-consumption of solar power in a household with a photovoltaic system and a battery storage system. The aim is to use the self-generated solar power as efficiently as possible and to minimize the use of electricity from the public grid.

How self-consumption optimization works:

1. Intelligent control of the energy flow: The hybrid inverter monitors the energy flow between the solar system, battery and home network.
2. Prioritization of self-consumption: The hybrid inverter prioritizes the use of solar power for direct consumption in the house.
3. Load shifting:
   • Excess solar power is stored in the batteries when the current electricity demand in the house is low.
   • The stored solar power is used later when the electricity demand in the house is high (e.g. in the evening or in the morning).
4. Adaptation to individual consumption patterns: Modern hybrid inverters can learn individual consumption patterns and adapt the self-consumption optimization accordingly.

Advantages of self-consumption optimization:

• Higher self-consumption: Self-consumption optimization can significantly increase the self-consumption of solar power.
• Lower electricity costs: The more solar power you use yourself, the less electricity you have to get from the public grid. This leads to lower electricity costs.
• Increased independence from the power grid: By using solar power and reducing the amount of power purchased from the grid, dependence on the public power grid is reduced.
• Environmental friendliness: The high level of self-consumption of solar power reduces greenhouse gas emissions.

Factors that influence self-consumption optimization:

• Size of the solar system: The larger the solar system, the more solar power can be generated and used.
• Size of the battery storage: The larger the battery storage, the more solar power can be stored and used later.
• Consumption behavior: The consumption behavior of the residents of the house plays an important role in efficiency the optimization of self-consumption.
• Smart home integration: The integration of the solar system into a smart home system can further improve the optimization of self-consumption.

Conclusion:

The optimization of self-consumption is an important part of a modern solar system with battery storage. By intelligently controlling the energy flow and using innovative technologies, the self-consumption of solar power can be significantly increased and electricity costs reduced.

Tip: It is advisable to seek advice from a specialist in order to determine the optimal configuration of the solar system and the battery storage for your individual needs and consumption patterns.

Monitoring the energy consumption of a solar system with a hybrid inverter offers numerous advantages:

• Increased transparency: You receive detailed information about the electricity generation of your solar system, your own consumption and the power you draw from the grid.
• Optimization of energy consumption: By analyzing your consumption data, you can identify opportunities to increase your own consumption and reduce electricity costs.
• Fault detection: Monitoring can help to identify and correct errors in the solar system at an early stage.
• Maintenance planning: The consumption data can be used to plan the maintenance intervals of the solar system.

Monitoring options:

1. Manufacturer portal: Most hybrid inverter manufacturers offer a web portal or app that allows you to view the consumption data of your solar system.
2. External monitoring systems: There are also external monitoring systems that are compatible with various hybrid inverters. These systems often offer more features and more detailed data than the manufacturer portals.
3. Energy management systems: An energy management system can network the solar system with other energy systems in the house, such as a heat pump or an electric car, and optimize energy consumption.

What information can be monitored:

• Electricity generation: The output of the solar system in watts or kilowatt hours (kWh) per day, month or year.
• Self-consumption: The electricity consumption in the house that is covered by the solar system, in kWh per day, month or year.
• Grid purchase: The electricity consumption that is drawn from the public grid, in kWh per day, month or year.
• Battery storage level: The charge level of the battery storage in percent.
• Error messages: Possible error messages from the solar system.

Additional functions:

• Visualization: Many monitoring systems offer a graphical representation of consumption data.
• Alarms: Alarms can be set, e.g. when the battery storage is almost empty or an error occurs in the solar system.
• Remote control: With some systems you can control the solar system and the battery storage remotely.

Recommendation:

The choice of the right monitoring option depends on your individual needs and your Budget. It is advisable to seek advice from a specialist before purchasing a monitoring system.

Tip: Make sure that the monitoring system is compatible with your hybrid inverter.

The prices for hybrid inverters vary greatly depending on performance, functions and manufacturer.

Note:

• Performance: The higher the performance of the hybrid inverter, the higher the price.
• Functions: Advanced functions such as emergency power supply or connection to smart home systems can increase the price.
• Manufacturer: Well-known manufacturers usually charge higher prices than lesser-known manufacturers.
• Scope of delivery: Some offers include the battery storage in the price, others do not.

Additional costs:

• Installation: The installation of a hybrid inverter should be carried out by a specialist. The costs for installation can vary depending on the effort involved.
• Commissioning: The hybrid inverter must be commissioned by a certified electrician.
• Maintenance: Hybrid inverters require regular maintenance. The costs for maintenance can vary depending on the manufacturer and maintenance contract.

There may be funding from KfW or other institutions for the purchase and installation of a solar system with battery storage. The amount of funding depends on various factors, such as the size of the solar system and the federal state.

Conclusion:

The costs for a hybrid inverter can vary greatly depending on the performance, functions and manufacturer. It is therefore important to seek advice from a specialist and obtain various offers before purchasing. With the help of subsidies, the purchase of a solar system with battery storage can be significantly cheaper.

The installation of a hybrid inverter is complex and should therefore only be carried out by specialists with appropriate training and experience.

Reasons:

• High voltage: When installing a hybrid inverter, high voltages are involved. This can lead to serious injuries or even death if the installation is not carried out professionally.
• Required expertise: Extensive knowledge of electrical engineering and photovoltaics is required to install a hybrid inverter. Laypeople can easily make mistakes that can lead to malfunctions of the solar system or even fires.
• Connections to the power grid: The hybrid inverter must be connected to the house network and, if necessary, to the public power grid. This should only be done by an authorized electrician.
• Warranty: Most hybrid inverter manufacturers only provide a warranty if the installation was carried out by a professional.

Dangers of self-installation:

• Electric shock: There is a risk of electric shock when working with high voltages.
• Fires: Incorrect installations can lead to fires.
• Damage to the solar system: Incorrect installations can damage the solar system.
• Power failure: Incorrect installations can lead to power failures lead.

Recommendation:

Always commission a specialist electrical or photovoltaic company to install a hybrid inverter.

The specialist company:

• Knows the applicable standards and safety regulations.
• Has the necessary specialist knowledge and experience.
• Can carry out the installation quickly and safely.
• Ensures that the solar system works properly.
• Gives you a guarantee on the installation.

The costs for installing a hybrid inverter vary depending on the performance of the inverter, the effort required for installation and the Location of the solar system. Typically, the cost is between €500 and €1,500.

Conclusion:

Installing a hybrid inverter is a complex task that should only be carried out by qualified personnel. Hiring a specialist company does involve additional costs, but it gives you the peace of mind that the installation will be carried out safely and professionally and that your solar system will function properly.

To ensure optimum performance and lifespan of your hybrid inverter, regular maintenance is required. Recommended maintenance intervals vary depending on the manufacturer and model, but are typically one year.

Scope of maintenance:

• Visual inspection: The inverter is checked for damage, dirt and corrosion.
• Functional test: The inverter's function is checked, including performance, efficiency and safety features.
• Cleaning: The inverter is cleaned of dust and dirt.
• Firmware update: The inverter's firmware is updated to the latest version.
• Documentation: The results of the maintenance are documented.

Additional maintenance measures:

• Depending on the manufacturer:
  • Checking the cooling system
  • Replacing wearing parts
  • Calibrating sensors
• If required:
  • Cleaning the contacts
  • Tightening screws
  • Checking the connections

Benefits of regular maintenance:

• Early detection of Errors: Regular maintenance allows errors to be identified and rectified early before they cause major damage.
• Extension of service life: Regular maintenance helps to extend the service life of the hybrid inverter.
• Increased performance: Regular maintenance ensures that the hybrid inverter functions optimally and delivers its full performance.
• Lower maintenance costs: Early detection of errors can often prevent expensive repairs.
• Increased safety: Regular maintenance helps to ensure the safety of the solar system.

Who should carry out the maintenance?

The maintenance of a hybrid inverter should be carried out by an authorized specialist company for electrical engineering or photovoltaics The specialist company has the necessary expertise and experience to carry out the maintenance safely and professionally.

Maintenance costs:

The costs of maintaining a hybrid inverter vary depending on the performance of the inverter, the effort required for maintenance and the location of the solar system.

Conclusion:

Regular maintenance of a hybrid inverter is important to ensure the optimum performance, service life and safety of the solar system. Although hiring a specialist company to carry out the maintenance involves additional costs, it gives you the peace of mind that your hybrid inverter is working properly and your investment is protected.

In Germany, there are various funding programs for the purchase and installation of a hybrid inverter with battery storage. The amount of funding depends on various factors, such as the output of the solar system, the federal state and the time of purchase.

The most important funding programs:

1. KfW funding:

• Program 420 Plus: Grant for the new installation of photovoltaic systems with battery storage.
  • Amount of the grant: Up to 40% of the eligible costs, maximum €10,000 for photovoltaic systems up to 10 kWp and €15,000 for photovoltaic systems over 10 kWp.
• Program 439: Repayment grant for the purchase of battery storage.
  • Amount of the repayment grant: Up to 25% of the eligible costs, maximum €6,250.

2. BAFA funding:

• Degressive feed-in tariff: A feed-in tariff is paid by the grid operator for solar power that is generated and not used by the user. The amount of the feed-in tariff is degressive, i.e. it decreases annually.

3. Regional funding programs:

• In addition to the nationwide funding programs, there are also regional funding programs in some federal states and municipalities.
  • You can obtain information about the regional funding programs from the responsible energy authority in your federal state or municipality.

Important:

• The funding conditions change regularly. Therefore, before purchasing a hybrid inverter, find out about the current funding options.
• The application for funding must usually be made before the solar system is installed.
• To apply for funding, you need various documents, e.g. a cost estimate for the solar system and proof of professional installation.

Conclusion:

The purchase of a hybrid inverter with battery storage can be financially supported by various funding programs. Therefore, before purchasing, find out about the current funding options in your region.

Tip: Get advice from a photovoltaics specialist who can help you choose the right solar system and apply for funding.