Solar Panels and Backup Batteries for Armenian Households and Companies

Photovoltaic Effect: The photovoltaic effect is the phenomenon where certain materials, typically semiconductors like silicon, generate an electric current when exposed to sunlight. This occurs due to the interaction between photons from sunlight and the semiconductor material, causing the release of electrons, which can then flow to produce electricity.

PV Cell: A PV cell, also known as a solar cell, is the basic building block of a PV panel. It consists of semiconductor materials, usually silicon, with specific electrical properties. When sunlight strikes the surface of the PV cell, it excites electrons in the semiconductor material, creating electron-hole pairs and generating an electric current.

Photovoltaic (PV) Cell

The most common types of solar cells are monocrystalline, polycrystalline, and thin-film. Monocrystalline cells offer high efficiency and longevity, while polycrystalline cells are cost-effective. Thin-film cells are lightweight and flexible, suitable for diverse applications.

Solar PV Cell Size And Peak Output.

Half-cut solar cells, created by halving standard-sized cells, offer advantages such as reduced resistive losses, enhanced performance in shading conditions, improved durability, and higher efficiency. However, they come with potential disadvantages, including increased manufacturing complexity and potential cell mismatch.

Full and half-cut PV cells

Half-cut cells: Power range Varies, but it is generally higher than full-size cells due to reduced resistive losses and improved shading tolerance. Actual dimensions: Half of the standard dimensions, e.g., approximately 78 mm x 78 mm for half-cut 156 mm cells.

PV Panel: A PV panel, also referred to as a solar panel, is a collection of PV cells interconnected to form a larger unit. The individual PV cells are typically encapsulated in a protective material and arranged in a specific configuration to maximize sunlight absorption and electricity generation. As sunlight hits the PV panel, each PV cell produces electricity through the photovoltaic effect.

While a solar cell generates a small amount of electrical power, a solar panel combines and interconnects numerous cells to produce a higher voltage and power output. In essence, the nominal power of a solar panel is the sum of the power output of all the cells of the panel.

Alternating current (AC) periodically changes direction, facilitating efficient transmission and compatibility with transformers. Direct current (DC) maintains a constant flow in one direction, ideal for batteries, electronics, and specific applications. Solar panels generate DC electricity, but homes typically use AC, requiring inverters to convert the power for household use.

Photovoltaic Effect: The photovoltaic effect is the phenomenon where certain materials, typically semiconductors like silicon, generate an electric current when exposed to sunlight. This occurs due to the interaction between photons from sunlight and the semiconductor material, causing the release of electrons, which can then flow to produce electricity.

PV Cell: A PV cell, also known as a solar cell, is the basic building block of a PV panel. It consists of semiconductor materials, usually silicon, with specific electrical properties. When sunlight strikes the surface of the PV cell, it excites electrons in the semiconductor material, creating electron-hole pairs and generating an electric current.

Photovoltaic (PV) Cell

The most common types of solar cells are monocrystalline, polycrystalline, and thin-film. Monocrystalline cells offer high efficiency and longevity, while polycrystalline cells are cost-effective. Thin-film cells are lightweight and flexible, suitable for diverse applications.

Solar PV Cell Size And Peak Output.

Half-cut solar cells, created by halving standard-sized cells, offer advantages such as reduced resistive losses, enhanced performance in shading conditions, improved durability, and higher efficiency. However, they come with potential disadvantages, including increased manufacturing complexity and potential cell mismatch.

Full and half-cut PV cells

Half-cut cells: Power range Varies, but it is generally higher than full-size cells due to reduced resistive losses and improved shading tolerance. Actual dimensions: Half of the standard dimensions, e.g., approximately 78 mm x 78 mm for half-cut 156 mm cells.

PV Panel: A PV panel, also referred to as a solar panel, is a collection of PV cells interconnected to form a larger unit. The individual PV cells are typically encapsulated in a protective material and arranged in a specific configuration to maximize sunlight absorption and electricity generation. As sunlight hits the PV panel, each PV cell produces electricity through the photovoltaic effect.

While a solar cell generates a small amount of electrical power, a solar panel combines and interconnects numerous cells to produce a higher voltage and power output. In essence, the nominal power of a solar panel is the sum of the power output of all the cells of the panel.

Alternating current (AC) periodically changes direction, facilitating efficient transmission and compatibility with transformers. Direct current (DC) maintains a constant flow in one direction, ideal for batteries, electronics, and specific applications. Solar panels generate DC electricity, but homes typically use AC, requiring inverters to convert the power for household use.

Solar yield, or the amount of electricity produced by a solar PV system, is influenced by various factors categorized into three major groups.

1. Climate Factors:

• Solar Irradiance is the amount of sunlight energy available for conversion into electricity, influenced by local climate conditions. According to the global horizontal solar irradiation map of Armenia, the sun energy falling on 1 square meter of horizontal plane is estimated to be between 3.47 and 4.56 kW/m2 annually.
• Temperature: Ambient temperature affects solar panel efficiency, with higher temperatures leading to decreased efficiency.
• Seasonal Variations and Weather Patterns: Changes in sunlight intensity, daylight hours, and weather conditions impact energy generation.
• Terrain Elevation: Higher elevations mean less air obstructing the sunlight’s path, resulting in more direct exposure to sunlight. Consequently, this increased exposure enhances energy capture efficiency and yields higher solar yields.

2. Roof-Specific Factors:

• To operate with maximum efficiency and generate electricity close to the nominal capacity, solar panels must be positioned to receive maximum sunlight exposure. In Armenia, the ideal orientation for optimal sunlight exposure is facing the South. The recommended tilt range for solar panels in Armenia typically varies between 25 to 35 degrees from the horizontal plane. This angle helps maximize sunlight absorption throughout the year, considering the country’s latitude and seasonal variations in the sun’s angle.
• Sub-optimal tilt and orientation of solar panels can decrease energy capture efficiency. Losses due to sub-optimal tilt angles may generally range from 5% to 15%, while losses due to sub-optimal orientation may range from 2% to 10%, depending on the degree of deviation. Addressing these factors during a solar PV system’s design and installation phases is crucial for maximizing energy generation and optimizing solar ROI.
• Obstructions such as buildings, trees, or nearby structures may cast shadows on the roof, reducing sunlight exposure to solar panels. Mitigating shading effects through proper site assessment and system design is essential for maximizing solar energy capture.
• Micro-inverters: Micro-inverters are ideal for mitigating the impact of non-optimal tilt, orientation, or shading on solar panels. Unlike traditional string inverters, micro-inverters are installed on each panel, allowing for individual panel optimization and minimizing losses due to sub-optimal conditions. This can improve overall system performance and higher energy yields, enhancing solar ROI.

3. Equipment-Specific Factors:

• Panel Quality and Efficiency: Solar panels’ quality, efficiency, and degradation rate influence energy generation and long-term performance.
• Inverter Efficiency: The efficiency of inverters impacts overall system performance and energy yield.
• Balance of System Components and System Design: The selection and quality of components and the design and configuration of the solar PV system influence energy production efficiency.

A reliable estimate of local PV potential is provided by Solargis through PVOut maps. These maps simulate various factors including theoretical potential, air temperature impact, system configuration, shading, soiling, and topographic constraints. PVOUT indicates long-term power generation per unit of installed capacity, measured in kilowatt-hours per installed kilowatt-peak (kWh/kWp). It’s important to note that PVOUT assumes an “average” PV setup with a central inverter and that a “perfect roof” is assumed, which may vary based on individual installation conditions.

To accurately assess your property’s electricity potential, a site inspection is essential. During this inspection, all the above-mentioned and more factors will be evaluated to determine the most suitable solar installation configuration for maximizing energy generation.

Solar panels generate DC electricity, but homes typically use AC, requiring inverters to convert the power for household use.

Alternating current (AC) periodically changes direction, facilitating efficient transmission and compatibility with transformers. Direct current (DC) maintains a constant flow in one direction, ideal for batteries, electronics, and specific applications.

Inverters also adjust the voltage levels to match the requirements of household appliances and the electricity grid. For example, a panel can generate 450V, but our home grid is 220V.

Standard inverters, or grid-tied inverters, convert solar panel-generated DC electricity into AC electricity for immediate use or export to the grid. They lack battery integration and offer no backup power during outages. In contrast, hybrid inverters combine solar and battery functions, enabling energy storage and backup power capabilities and providing greater energy independence.

Micro-inverters are installed on individual solar panels, independently converting DC electricity to AC, optimizing performance, and offering panel-level monitoring. Central inverters, installed centrally, convert combined DC electricity from multiple panels into AC. They are cost-effective and simpler to install but lack panel-level optimization. The choice depends on system size, shading, monitoring preferences, and safety requirements.

Microinverters connect panels in series and central inverters in parallel.

Inverters generally have efficiency ratings ranging from 90% to 99%, indicating the percentage of DC electricity converted into usable AC electricity. Optimal systems can achieve efficiencies nearing 99%, maximizing energy conversion and system performance, while less efficient models may fall closer to 90%, resulting in higher energy losses.

Inverters are the most loaded equipment in solar stations. The warranty period is crucial as it guarantees the reliability and longevity of the inverter, ensuring uninterrupted operation and protecting the investment in the solar PV system. Typically, warranties for inverters range from 5 to 25 years, depending on brand quality.

Optimizing solar farm efficiency demands precise alignment of every system element with both internal and external conditions. From mitigating shading to orienting panels to the sun’s path and ensuring proper placement of ancillary components, meticulous alignment maximizes sunlight exposure and energy production.

Micro-inverters connect each solar panel in parallel, allowing each panel to operate independently. This means that shading, debris, or a malfunction on one panel does not affect the performance of the others. In contrast, central inverters use a series connection, where the performance of the entire system can be compromised if even one panel underperforms. This parallel connection of micro-inverters ensures maximum energy production and efficiency.

Serial connection of solar panels

Parallel connection of solar

panels

At R-Fab, before presenting our products to customers, we rigorously test each piece of equipment to align marketing claims with real-world performance. Fortunately, our co-founder and Chief Technology Officer owns a stunning home in the verdant suburbs of Yerevan, which serves as a testing ground for the equipment we install.

The roof presents challenges for solar installation: it has an A-shape with facets facing East and West, with a tilt of 30 degrees, whereas the optimal angle is 40 degrees. Furthermore, shade from nearby trees affects different roof parts depending on the season and time of day.

We invited two reputable Armenian solar installation companies to propose solutions to ensure impartial evaluation. If you ever Googled “solar panels in Armenia” or “arevayin panelner,” you likely saw both companies on the first page of the search results.

One installer declined to proceed after assessing the site, citing that their solar farm with a central inverter couldn’t produce sufficient electricity to justify the installation financially.

The second company proposed a 4.3 kW system comprising 8 540W tier-1 JA Solar panels paired with a 4.3 kW Solis central inverter, priced at 1,540,000 AMD, or 358 AMD per watt. They claimed an annual generation of 6020 kWh, contingent upon positioning the setup on a custom metal mounting above the trees to mitigate shade. Additional costs for this mounting, including removing cladding, were to be borne by the homeowner.

Now, let’s compare these offerings with our micro-inverter-based solar farm. Our setup features 10 435W tier-1 panels by Longi paired with NEP BDM-800 micro-inverters. Notably, our panels lie seamlessly on the roof without unsightly structures, yielding 6522 kWh. Both setups are priced identically – 358 AMD per Watt, but R-Fab offers several advantages:

1. Despite the suboptimal placement and shades, our micro-inverters match the energy generation of perfectly positioned central inverters.
2. While the price is the same 358 AMD per Watt, micro-inverters come with a 12-year warranty against a 5-year warranty for Solis central inverter. 
3. You don’t need to spend extra money and time to build an ugly and potentially hazardous mounting for the setup with a central inverter.