• Ginlong Solis and Enerparc believe string inverters have an advantage over central inverters for utility scale projects
  • String inverter costs are now almost at par with central inverters but can do away with the need for combiner boxes
  • These are easier to install, maintain and operate and even be replaced easily compared to central inverters whose replacement at the same nominal power is difficult to find in the market
  • String inverters now also support storage making these a suitable fit for utility scale projects

One of the most essential components of a solar PV system is an inverter that, as we all know, converts direct current (DC) solar energy into alternating current (AC) without which power supply isn’t possible in today’s grid-connected world. Of late, the string inverter, as the ‘brain’ behind a rooftop solar system,  is fast making its mark in the large scale solar power plant space as well, competing directly with central inverters that hitherto have dominated the utility scale scene.
To understand what is it that string inverters bring to the table for utility solar projects, TaiyangNews invited Chinese solar PV inverter manufacturer Ginlong Solis and independent power producer, developer and EPC company with German roots, Enerparc AG for a webinar titled Advantages of String Inverters in Utility Scale Solar Plants—Views from A Leading Manufacturer and Developer/EPC on November 2, 2020. Ginlong is a Chinese stock-listed company, with big expansion plans that will turn it into one of the world’s largest producers in that segment next year. Enerparc is a Germany headquartered PV developer/EPC, which is also the country’s largest solar IPP:
Enerparc’s Team Leader Systems Engineering, Armin Scherl delved into the design aspect of PV inverters in the utility scale solar plants space to drive home the point that string inverters are easier to install, operate, maintain and even replace vis-à-vis central inverters that are comparatively more complex systems. The latter need to be accompanied by DC combiners and need concrete foundation making it a time consuming affair. It is also with ‘great difficulty’ to find central inverters in the current market with the same nominal power if older ones need to be replaced.
Backing Scherl’s claims was Head of Utilities for Solis USA, Gary Lam who, representing the manufacturing side, presented the cost comparison of string as well as central inverters. Between 2010 to 2023, string inverter cost has been seen to come down to almost the same level as central inverters and by the end of the projected period, it should be more or less the same. Besides cost, Lam also gave several reasons to opt for string inverters in large scale power plants.
Lam argued that string inverters have the ability to support storage as well which is a big plus for the technology considering the fact that an increasing amount of renewables would need storage to stabilize the grid as the industry moves forward. At the same time, string inverters can replace combiner boxes, enabling capex cost control while improving opex. When he presented his company’s newest string inverter offering, Solis 1500V 255kW, in this space, he underlined the key differentiators – high DC/AC ration, high yields, smart O&M. With high efficient cooling design and redundant fan central, he emphasized that the product is 25-years maintenance free.
Recently while announcing its strong Q3/2020 financials, Ginlong Solis said it was building a new smart manufacturing facility with 15 GW of annual production capacity to increase its aggregate capacity to 20 GW by 2021, increasing from currently 5 GW (see Ginlong Solis Calls Q3/2020 Its Strongest Quarter Ever).
The recording with presentations and Q&A of the Advantages of String Inverters in Utility Scale Solar Plants—Views from A Leading Manufacturer and Developer/EPC webinar can be viewed on YouTube.