Before we discuss the factors that can make highly efficient PV inverters, let’s learn the definition of what the efficiency is at first. It refers to the rate that a PV inverter converts the direct current generated from sunlight into the alternating current which is used directly by each family. After making the definition clear, we can discuss the factors.
A PV inverter is a machine which produces heat while working. Usually a machine’s working efficiency reduces as its heat grows. Indeed this is the same for a PV inverter. From this perspective, we know if it can keep cool while working, they can work more efficiently. Out of this concern, the inverter with a cooling system inside has been invented and is being used. Omnik’s micro inverters are a typical example of this kind. At the same time, to make an efficient inverter work better, users can install it in the places of a house where sunlight cannot reach, as so to make it cool. In addition, voltage optimization and inverter load are aslo two important elements that influence the efficiency. The inverter load is the amount of power that the inverter is supplying compared to its rated power. The following picture shows how an inverter’s efficiency changes as its output power changes.
Today, the highest solar inverter technology originates from Europe, especially Germany. The most excellent technology it holds is the high frequency isolation technology, which can protect the inverter from damage and make it work more efficiently. Currently the highest solar inverter efficiency can reach up to 98.5%. The most efficient micro inverters (mainly used for residential solar PV systems) have the highest efficiency of 96% or so.
In the world there are numerous solar inverter manufacturers, and some of the big names are really producing high efficiency inverter products, including SMA (98.5%), SolarEdge (98%), Advanced Energy (98%), Kaco (98%) and Siemens (98%). In fact, there are also other highly efficient products including Omnik (98.2%) that product excellent inverter products. To learn more, please check this information and clear your confused mind.
Some inverters have a high efficiency when they output in highest power, but have low efficiency when they output in lowest power; and some even have an average conversion efficiency when they output from low power to high power. Therefore, when choosing solar inverters, you need to consider whether the solar panels’ output characteristics match the features of the solar inverters or not.