Solar energy is one of the most reliable and robust sources of renewable energy available to mankind today. Countries around the world are banking on solar based energy solutions, not only to meet rising energy demands but also to combat climate change and arrest environmental degradation.
This global increase in demand for solar energy has given rise to the demand for all key components for setting up a solar plant. The most apparent component of any solar plant is the solar PV modules which harness the sunlight to produce solar energy. However, the electricity generated is not readily usable and requires the intervention of an equipment known as a solar inverter.
Solar inverters are an integral part of any solar installation and are often considered the brain of the system, regardless of the size of the solar plant. These inverters are available in various capacities, installed as per the scale of a solar installation. Equipped with the latest technology for improved efficiency and a high degree of system redundancy, solar inverters present a clean energy solution for a wide variety of residential as well as commercial applications. Modern solar inverters are aesthetically designed and capable of powering regular home appliances like air conditioners, refrigerators, TVs and microwaves, etc. In addition to making solar energy accessible and practical for the end users, solar inverters can feed excess power to the grid and help achieve substantial savings in electricity costs.
A Solar Inverter is the heart of the Solar power System which converts DC Power generated from Solar Modules to AC Power which is used to run Electrical Products. Solar inverters are alternative power back-up solutions with a cost advantage. Here’s how it works:
- Worried with High Electricity Bills?
Install a Solar System using high efficiency MPPT based On Grid String Inverters. Suitable for Residences, Offices, Institutes, industries and Hospitals .
- Need Power Backup during Power Cut?
Install a Solar System Using Off Grid Solar Inverters & Solar Batteries to run your appliances during power cuts. Suitable for Residences, Offices, Schools etc.
- Need Power Backup with the Option to Export Extra Solar Power?
Install Solar System using Hybrid Smart PCU which uses Solar as priority to charge batteries along with running of load. Once batteries are fully charged & load is less, excess power is exported to the Grid Using Net Metering. Suitable for Residences, Offices, Schools, Hospitals and so forth.
Since all commercial appliances run on AC power as a standard, inverters are generally considered as the gateway between the solar plant and the end users. Moreover, AC power is the only suitable medium for electricity transmission via cables over large distances.
Function of Solar Inverters in Solar Plant
Apart from the basic function of converting DC into AC, a solar inverter primarily plays the following roles in a solar power system:
- Maximizing the energy production of a solar plant
- Ensuring safe operations of the entire system
- Assistance to the power grid in case of on-grid inverters
- Constant monitoring, reporting and tracking of power output
Solar Inverter Classification
Over the years, there has been significant development in solar inverter technologies. In addition to converting DC to AC, modern solar inverters offer multiple capabilities and services ensuring optimal performance of the solar plant. Primarily, solar inverters can be classified into Off-grid / hybrid inverters and On-grid inverters. However, depending upon the application, technology used and functions, the solar inverter market can be segmented into string inverters, central inverters and micro-inverters.
- Off-grid / hybrid inverters: Off-grid inverters are used for applications where the PV plant is not connected to the grid or the main energy distribution network. Typically such a PV installation is coupled with a battery storage system which ensures energy supply during non-sunlight hours as well. The inverter charges the batteries and the connected loads while ensuring the stability of the main electrical parameters of voltage and frequency. This allows the inverter to remain within predefined limits and withstand any temporary overloading situations.
- On-grid inverters: On-grid inverters, on the other hand, are designed to export solar power into the main power grid by matching their corresponding phase and frequency. These inverters have the capability to automatically disconnect in case of any system failure to protect grid stability. On-grid inverters are most suitable for application in areas with reliable grid supply and equipped with net-meter, it can result in considerable reduction in electricity costs.
- String Inverters: String inverters are most commonly used solar inverters and usually do not come equipped with battery back-up capabilities. These inverters are usually directly connected to the grid and are suitable for small to medium scale solar installations, typically under 1 MW capacity. Suitable for both commercial and residential purposes, these type of inverters offer features such as high efficiency, minimal losses, easy maintenance, and offer high degree of design flexibility for a solar plant installation.
- Central Inverters: Central solar inverters are generally used for large commercial installations or utility-scale solar farms. These are highly efficient systems and are capable of advanced features such as power conditioning, load balancing, etc. Typically available in capacity upwards of 300 KW, central inverters are bulky and require storage in temperature controlled environment for optimal performance.
- Micro-inverters: A micro inverter is a small inverter usually located on the back of a solar module. Unlike string or central inverters which convert DC power from an array of solar modules, a micro inverter performs DC to AC conversion for a single solar module. Such inverters are usually used for off-grid applications but suffer from lower efficiency and high maintenance costs.
Solar Inverter Market Trends in India
The most important reason behind the growth in demand for Solar Inverters in India lies in favourable government policies on developing renewable energy resources for power generation. India’s National Solar Mission of producing 100GW solar resources is the single biggest factor towards long term demand of the solar inverters. In addition to this, there is renewed focus from the government on developing smart cities and the government is investing heavily in clean and free energy sources, thereby surging the demand for solar inverter further.
Another factor to be considered is the rising consumer interest in usage of solar energy, especially among the residential, industrial, and commercial consumers. This is due to the potential benefits of reduced electricity costs and will continue to pave the way for market growth.
However, factors such as high initial investment, intermittent power generation, requirement of a large area for installation, etc., which impact the solar PV sector in general continue to impact the solar inverter market.
To sum up…
Solar inverters are going to play a crucial role in further expansion and penetration of the solar PV industry. With module prices being more or less saturated, the industry is looking up to the inverter manufacturers to come up with innovative products which will help in bringing down cost, while maintaining key attributes for a solar energy system like reliability, efficiency and features such as data monitoring, advanced utility controls and applications. Close co-ordination between the manufacturers and end-users is needed for providing post-installation services such as preventative maintenance, O&M services that are integral to maintaining energy production and a high level of performance for any solar project.