Author: reon

Sleep deprived and starved, I rushed from Munich International Airport to Messe München just in time for the Intersolar exhibition. On stepping out of the airport, I was met with some cool breeze, enough to wash away my weariness.

I started off my first day exploring the Smart Solar PV Inverters and battery storage solutions. The most common PV inverters are still string and central inverters; however, these are not commercially feasible options for large scale solar solutions. The winner on Day 1 was smart battery storages mostly based on the lithium and zinc ion technologies. These smart storage options came with compact container sized solutions with a battery life of at least 5000 to 6000 cycles and flexibility to get charged from either grid or solar, based on availability.

For the majority of the off-grid communities, financial restrictions and operational inefficiencies of the system further amplify the challenge of electrification for Distribution Companies (DISCOS). Rural set-ups with lower electricity demand and lower capacity to pay as opposed to their urban counterparts make urban centers the priority for DISCOS. Moreover, for those rural set-ups connected to the grid, insufficient energy access is widened due to inter-province electricity distribution and rural-urban divide. In such instances, microgrids present a viable alternative to the centralized grid infrastructure. Microgrid enhances energy resilience and recovery, reduces energy costs for customers and businesses as energy is now produced near to the consumer that helps reduce line losses and theft.

Quality control is simply a tool that can assess the quality of a company’s products and services against a predetermined parameter. QC is a vital requirement to build a successful business that is able to fulfil customer demands and expectations.

Quality Checks ensure that the performance of the solar plant is at par with the global standards. These checks include in-house and third-party audits to spot operational troubles in electrical parameters, wiring, cabling, structure, alignment and performance ratios. IV Curve tracing and Heat Maps are a few techniques used to ensure optimum performance.

With an increase in temperatures, the solar panels become less efficient and generate lesser energy. They may even get damaged with some defects causing them to break down or generate a reverse current, which may, in turn, damage the entire Solar Plant. Thermal Imaging can help detect any presence of hot spots on the panels. They can be used to inspect entire solar systems; from panels to connections, fuses, inverters and all components of the system. This makes it substantially easier to detect faults on the panels before they cause any devastating breakdowns.

I-V Curve Tracing is a method of electrically testing the PV module and photovoltaic array and ensuring that it performs at optimum level. This test can be conducted at any time during the manufacture, installation, commissioning, performance and troubleshooting phase to ensure productivity. A device, called the I-V Curve Tracer can be installed for this purpose, which measures current and power as a function of voltage. This test can be applied on individual strings and the captured results can be compared to expected results for any variation.

I-V Curve tracing helps in determining the optimum combination of current and voltage to maximize yield as illustrated in the figure below. The red line depicts maximum output achieved through the best combination of current and voltage whereas the dotted line shows reduced output which may be a result of several factors such as a module mismatch, soiling, and more.

In commercial and utility-scale applications, panels are elevated and angled away from the mounting surface allowing light that strikes the ground to reflect back upwards enabling bifacial cells to absorb greater sunlight. Essentially, with bifacial modules, there are now two optimal sun hours (peak hours) of the day opposed to just one because of the dual sides. Thus, generating greater energy yield without having the need to occupy additional space.

In traditional Solar PV fixed-tilt Plants, the power output follows a bell curve throughout the day, it gradually increases until peaking at noon, then returns to decrease. Whereas, in single-axis Solar PV Plants, we approach the maximum power from early in the morning and this production is maintained until late afternoon. Hence, seeing a performance gain of approximately 25% (Energy Sage, 2019) as compared to the fixed PV installation.

Ground mounted solar panels can be placed anywhere in a field or yard that sees the sun for majority of the day. Ground mounting requires a dedicated space in the field or yard to set up the panels. These are an ideal choice for commercial and industrial businesses that have excess availability of land. Some of the ground types where panels can be installed are:

Hot-dip galvanized steel structures are made with fabricated steel sheets that are coated in zinc to keep them corrosion free. While regular steel is composed of iron which rusts to the point of disintegration on prolonged exposure to moisture, galvanized steel structures ensure structural durability by creating a physical barrier that prevents water from reacting with iron.

This method of galvanization is two to three times more expensive than pre-galvanized mounting structures. However, while pre-galvanized structures may be fairly popular among Solar Plant Installers due to their cost advantage, they are not sustainable in the longer run and could rust, corrode and crumble when exposed to rain, humidity, etc in access.