What is an inverter as part of a solar p.v. Installation

Introduction to Solar Inverter Technology

A solar inverter plays a vital role in converting the electricity generated by solar panels into a form usable for homes. It works by transforming the direct current (DC) produced by solar panels into alternating current (AC), which is used in household appliances. Unlike DC, which moves electrons in one direction, AC enables movement in both directions. This makes AC a more practical choice for residential use due to lower transmission losses over long distances and its overall ease of generation. Moreover, AC is considered safer than DC.

Solar Energy Conversion During Daylight

During sunlight hours, solar panels generate DC electricity, which is then transmitted through the system and DC cabling into the solar power inverter. Since household appliances are designed to operate on AC, the energy must be converted to make it usable in homes.

Types of Solar Inverters: String Inverters and Microinverters

A string inverter connects a number of panels together to form a string.

String Inverters

There are two primary types of solar inverters: string inverters and microinverters. String inverters, cost-effective and ideal for roofs with minimal shading, are designed to handle one or two orientations efficiently.

They connect multiple panels into strings (commonly known as a circuit) before feeding into a single inverter unit.

Microinverters

Micro inverter connects to individual panels to reduce potential shading impact. The above connects to two panels.

In contrast, microinverters are attached to each panel, enabling independent operation, mitigating shading concerns, and offering flexibility in panel orientation. While they yield higher generation figures in potentially shaded scenarios, they involve more components, increasing the risk of malfunctions. Accessing microinverters for repair or replacement can be challenging and expensive compared to the centralised setup of string inverters.

A hybrid inverter can work with both a solar PV installation and a battery storage system at once.

Hybrid Inverters: Integrating Energy Storage

Another consideration is the hybrid inverter, which is beneficial for directing energy to solar batteries and converting it to AC when required in the house. Retrofitting a battery may not necessitate a hybrid inverter if there is no battery included in the system, as a standard inverter can manage the process. However, upgrading to a hybrid inverter during a system replacement or when components are ageing could be a worthwhile investment, so that if you add batteries to your system in the future, another inverter would not be needed.

Enhancing Efficiency with Solar Panel Optimisers

Additionally, solar panel optimisers work at the individual panel level, enhancing efficiency. Similar to microinverters, optimisers isolate the impact of underperforming panels, ensuring maximum energy production by constantly monitoring and regulating voltage, current, and temperature for each panel.