New & innovative: Decentralized and modular plug & play solar system - different from the others

There is a wide variety of photovoltaic systems available on the market, ranging from string inverters to hybrid and central inverter-operated solar systems.

There is also a wide variety of products available to meet the diverse needs of buyers. Comparing different photovoltaic products is therefore essential to finding the best offer. First, I would like to outline the various factors that should be considered when choosing a photovoltaic system.

performance

An important factor is the system's performance, that is, what performance and efficiency can be expected.

Price-performance-quality guarantee

Price also plays a role: Photovoltaic systems should be chosen that offer good value for money. Quality standards and warranty periods, as well as specific requirements for installation and maintenance of the system, are equally important.

technology

Another factor is the different technologies used in the production of photovoltaic systems. There are various methods for manufacturing solar cells, including monocrystalline cells, polycrystalline cells, and amorphous cells. Each type has its own advantages and disadvantages in terms of efficiency and cost-effectiveness. Therefore, it is important to understand which technology best suits your needs.

Performance, service, and support

Finally, other factors also play a role when comparing photovoltaic offers. These include service offerings such as installation and maintenance, as well as warranties and insurance conditions in case of damage or theft of the system.

Energy concept & planning security

Besides its size and dimensions, your solar system should align with your energy concept. This primarily refers to the goals you intend to achieve with your solar system and what you plan to implement in the future. The development of energy costs and your overall cost management significantly contribute to your planning security.

Suitable for:

• Solar & Photovoltaics: Energy concept & planning security for B2C from B2B

The ideal solar system for up to 40 kWp – Image: Xpert.Digital

In contrast to a string inverter, which records all connected solar modules (centrally), in a decentralized solar system each solar module is combined with an Enphase micro inverter.

Enphase Energy has launched the world's first micro-inverter capable of forming a local microgrid.

This decentralized version of a solar power system has several advantages:

➡️ Related: Enphase Inverters: Test and Experiences 2023

➡️ Each individual solar module can be monitored remotely via the respective micro-inverters using software. Performance is analyzed down to the module level, faults are detected, and failures are identified.

In addition to the website browser version, there is also the MyEnlighten app for mobile devices, which allows you to monitor the energy production of your Enphase system on the go.

Enphase – Image: T. Schneider|Shutterstock.com

➡️ Each micro-inverter has an MPPT (Maximum Power Point Tracker) for each individual module, responsible for optimizing the performance of that specific solar module. Temporary shading does not negatively affect the other solar modules, unlike a (central) string inverter: When a solar cell is shaded, the current flow behaves similarly to water being forced through a kink in a garden hose. The overall current flow is obstructed by the shading, and the intensity of all solar modules connected to the (central) string inverter is reduced. String inverters typically have "only" 1-2 MPPTs for all connected solar modules.

In electrical engineering, specifically in photovoltaics, Maximum Power Point Tracking (MPP tracking) refers to a method in which the electrical load on a solar cell, a solar module, or several solar modules connected in series (a "string") is adjusted to extract the maximum possible power from the cells. For solar cells, this optimal operating point is not constant but depends on factors such as irradiance, the temperature of the solar module, and the type of solar cell.

➡️ Optimizers for solar modules in case of shading, in conjunction with string inverters, are no longer necessary because microinverters already handle this task in cases of partial shading. This results in significant cost savings, which is why the use of microinverters for solar systems up to 40 kWp can be more cost-effective than using conventional string inverters.

➡️ In addition, system updates can be applied to the micro-inverters via the Enphase Envoy Gateway (a communication interface via the Internet).

Enphase Envoy® Communication Gateway™ and MyEnlighten – Image: Enphase

➡️ Compared to conventional string inverters, Enphase micro-inverters come with an industry-leading warranty of up to 25 years.

Industry-leading warranty service – Image: Enphase

➡️ Do you want to expand your solar system with additional modules? That's no problem either. Thanks to the Plug & Play connector system (IQ Cabling), you can expand your system with additional microinverters in combination with the solar modules you wish to use.

Enphase IQ Cabling – Image: Enphase

Suitable for:

• Enphase Microinverter Datasheet
• Enphase IQ Cabling

If one microinverter fails, solar power generation can continue using the remaining microinverters. However, in a system with a central string inverter, generation is completely interrupted. Furthermore, the Enphase Solar design offers superior safety features, as it operates on low-voltage alternating current.

Enphase micro-inverters – Image: Enphase

Enphase – all in one system – Image: Enphase

Enphase with energy storage – Image: Enphase

Installing an Enphase system requires installing the micro-inverters, the IQ battery (if required), and other essential components.

Suitable for:

• Enphase PDF: On-site assembly instructions for Germany

String inverter/string inverter

A string inverter connects a series of photovoltaic modules, converting the supplied direct current (DC) voltage into alternating current (AC) voltage. For systems with multiple strings, a multi-string inverter is available. String inverters are by far the most commonly used type in residential solar power systems.

Module inverter

A single microinverter is attached to a solar module, converting the direct current (DC) into alternating current (AC). The outputs of the various microinverters are then connected in parallel and fed into the power grid.

Central inverter

A central inverter is typically only used in very large photovoltaic systems and requires dedicated technical equipment, often occupying many square meters. This type of inverter is usually used by professional operators.

Hybrid inverter

A hybrid inverter is distinguished by its ability to convert the direct current (DC) from your solar system into usable alternating current (AC). Furthermore, it can store solar power in an internal or external solar battery. Newer hybrid inverters are capable of providing emergency power or black start capability . Typically, a hybrid inverter is a string inverter with enhanced energy storage functionality.

Microinverter

Microinverters are essentially module inverters. They convert the direct current (DC) generated by the solar panel directly into alternating current (AC) on site. Microinverters gained widespread popularity in the field of balcony power plants or balcony solar systems for 1-3 solar panels, which are plugged directly into the household electrical system using a standard IEC power connector.

• Quick and easy assembly.
• Minimal material costs.
• Inverter is located directly on the solar module, flexible orientation,
• This allows the modules' power to be converted optimally.
• Enphase microinverters are smart grid compatible .
• Enphase microinverters meet complex grid requirements regarding voltage and decoupling management.
• Enphase inverters enable remote updates and adaptation to future grid requirements.

The IQ System Controller is not yet available in Germany, but is expected to be released this year (2023). It detects when the power grid fails and seamlessly switches the house from mains power to backup power.

Suitable for:

• Black start power storage: Hybrid inverters like energy storage capable of black start? Against temporary power failures and blackouts

Additionally, with the new Enphase IQ8 microinverter, the solar system is capable of providing backup power in the event of a power outage without the need for battery storage.

The microinverter is available in four versions: as a solar-only version without emergency power function and as a sunlight backup version with the ability to operate off-grid without battery storage. The system is also available in combination with a small battery storage in the Home Essentials backup version and with large storage as a full energy independence version. All three of the latter off-grid solutions must be equipped with an Enphase System Controller to provide solar power to the home during a power outage.

Solar roof – Roof PV consulting with Xpert.Solar – Konrad Wolfenstein – Image: Xpert.Digital

Anyone who has ever thought about the question will get many different answers.

More about it here:

• Here is a rough overview of the respective price levels for a 10 kWp rooftop PV system with electricity storage as an example.