R. S. Enterprises Shop No. 2, Dudoli, Rahim Nagar, Lucknow - 226001
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What Is Solar ?

Solar energy is, simply, energy provided by the sun. This energy is in the form of solar radiation, which makes the production of solar electricity possible.
Electricity can be produced directly from photovoltaic, PV, cells. (Photovoltaic literally means “light” and “electric.”) These cells are made from materials which exhibit the “photovoltaic effect” i.e. when sunshine hits the PV cell, the photons of light excite the electrons in the cell and cause them to flow, generating electricity.
Solar energy produces electricity when it is in demand – during the day particularly hot days when air-conditioners drive up electricity demand. In use, solar energy produces no emissions. One megawatt hour of solar electricity offsets about 0.75 to 1 tonne of Co2.

On Grid / Grid Tied Solar System

Solar Rooftop PV(Photo Voltaic) system using On-grid is also termed as a Grid-tied system or Utility interactive or Grid back feeding or Grid intertie system. In this kind of system, the Solar is connected with utility grid ( typically the power lines).In pure on-grid solar PV system, batteries are not connected.
Once the Solar generation starts all the generated energy tries to compensate the existing loads. Once all the loads are satisfied excess generation will be going to the grid. Grid by itself acts as a virtual battery taking in all the excess energy exported. When there is a shortage(or even when there is zero generation) in energy generation from the Solar rooftop for all the available loads excess required energy is imported from the grid. By end of every month based on total export and import billing will be done. This net will be calculated with the help of a Bi-directional meter or net meter. A net meter is a device that records the energy supplied to the grid and the energy consumed by the consumer.

Advantages

• PV panels provide clean – green energy. During electricity generation with PV panels there is no harmful greenhouse gas emissions thus solar PV is environmentally friendly.
• Solar energy is energy supplied by nature – it is thus free and abundant!
• Solar energy can be made available almost anywhere there is sunlight.
• Solar energy is especially appropriate for smart energy networks with distributed power generation – DPG is indeed the next generation power network structure!
• Solar panels cost is currently on a fast reducing track and is expected to continue reducing for the next years – consequently solar PV panels has indeed a highly promising future both for economical viability and environmental sustainability.
• Photovoltaic panels, through photoelectric phenomenon, produce electricity in a direct electricity generation way.
• Operating and maintenance costs for PV panels are considered to be low, almost negligible, compared to costs of other renewable energy systems.
• PV panels have no mechanically moving parts, except in cases of suntracking mechanical bases; consequently they have far less breakages or require less maintenance than other renewable energy systems. (e.g. wind turbines)
• PV panels are totally silent, producing no noise at all; consequently, they are a perfect solution for urban areas and for residential applications.
• Because solar energy coincides with energy needs for cooling, PV panels can provide an effective solution to energy demand peaks – especially in hot summer months where energy demand is high.
• Though solar energy panels’ prices have seen a drastic reduction in the past years, and are still falling, nonetheless, solar photovoltaic panels are one of major renewable energy systems that are promoted through government subsidy thus financial incentive for PV panels make solar energy panels an attractive investment alternative.
• Residential solar panels are easy to install on rooftops or on the.
• Ground without any interference to residential lifestyle.

Off-Grid Standalone Solar System

An off-grid solar system is a self-sustaining energy setup that operates independently from the utility grid. It typically consists of solar panels, batteries, charge controllers, and sometimes a backup generator. Here are some key points about off-grid solar systems:

• Solar panels: The solar panels are installed on rooftops or ground-mounted to capture sunlight and convert it into electricity through the photovoltaic (PV) effect.
• Batteries: Energy generated by the solar panels is stored in batteries to be used during times when the sun is not shining (e.g., nighttime or cloudy days). Batteries play a crucial role in providing power when solar generation is insufficient.
• Charge Controllers: Charge controllers regulate the flow of electricity between the solar panels and batteries. They help prevent overcharging or discharging of batteries, which can damage their lifespan.
• Inverter: Off-grid systems use inverters to convert DC (direct current) electricity generated by the solar panels and stored in batteries into AC (alternating current) electricity, which is suitable for powering household appliances.
• Backup Generator: Some off-grid setups may include a backup generator to provide additional power during extended periods of low solar production or high energy demand.
• Energy Management: Proper energy management is critical in off-grid systems. Users must carefully monitor their energy usage to ensure they do not deplete the battery reserves.
• Remote Locations: Off-grid solar systems are popular in remote locations where connecting to the utility grid is impractical or expensive.
• Energy Efficiency: Maximizing energy efficiency in an off-grid setup is essential to make the most of the available solar resources and battery storage.

It's important to note that designing and installing an off-grid solar system requires careful planning, taking into account factors like energy consumption, location, available sunlight, and storage capacity. Consulting with a renewable energy professional is recommended to ensure a well-designed and efficient off-grid solar system tailored to your specific needs.

Hybrid Solar System

A hybrid solar system, also known as a grid-tied solar system with battery storage, combines the benefits of both grid-tied and off-grid solar systems. It allows users to generate and use solar energy while being connected to the utility grid and incorporating battery storage for backup power. Here are some key points about hybrid solar systems:

• Solar panels: Like in grid-tied systems, solar panels capture sunlight and convert it into electricity through the photovoltaic (PV) effect.
• Grid Connection: Hybrid systems are connected to the utility grid. During times when the solar panels produce more electricity than needed, the excess power can be fed back into the grid, earning credits or compensation (net metering) from the utility company.
• Battery Storage: The main differentiator of hybrid systems is the inclusion of battery storage. Excess solar energy generated during the day is stored in batteries for later use, such as during the night or in case of power outages.
• Inverter: Hybrid systems use a specialized inverter that manages the flow of electricity between the solar panels, batteries, and the grid. It can switch between grid-tied and off-grid modes as needed.
• Energy Management: Hybrid systems rely on advanced energy management systems to intelligently decide when to use solar power, when to store excess energy in batteries, and when to draw power from the grid.
• Backup Power: The battery storage in a hybrid system provides backup power during grid outages, ensuring continuous electricity supply to essential loads in the home or business.
• Optimized Self-Consumption: Hybrid systems aim to maximize self-consumption of solar energy, meaning that the solar power generated is used on-site rather than being exported to the grid.
• Flexibility and Cost Savings: Hybrid systems offer flexibility and cost savings compared to off-grid systems, as they allow users to benefit from net metering and reduce reliance on grid power while still having backup power when needed.

As with any solar system, designing a hybrid solar system requires careful consideration of energy consumption patterns, available sunlight, battery capacity, and other factors. Professional guidance is recommended to ensure the system is efficiently tailored to meet your specific energy needs and requirements.

Technical Information

SOLAR RADIATION AVAILABILITY

Solar radiation is the radiant energy emitted by the Sun in the form of electromagnetic waves.

• The sun emits vast amount of radiant energy.
• The earth intercepts only a fraction of it.
• It is essential to drive directly or indirectly all biological and physical processes on the Earth.
• The earth is the only planet in the solar system, which receives an optimum amount of solar radiation that makes life sustainable on it.
• Solar spectrum resembles to that of a black body at approximately 5800K
• 98% of the total emitted energy lies in the spectrum ranges from 250nm to 3000nm. About half of the radiation is in the visible shortwave part of the electromagnetic spectrum. The other half is mostly in the near-infrared part, with some in the ultraviolet part of the spectrum.
• Solar radiation having wavelength less than 0.286nm (called ultraviolet) is absorbed by ozone layer in stratosphere. The ultraviolet radiation not absorbed by the atmosphere is responsible for the change of color in skin pigments.
• The solar radiation, that traverse the atmosphere further, is subjected to scattering, reflection and absorption by air molecules, aerosols and clouds.
• The radiation budget represents the balance between incoming energy from the Sun and outgoing thermal (longwave) and reected (shortwave) energy from the Earth. Globally, the budget is balanced. Otherwise the temperature would rise constantly. Locally, the budget is not balanced. Tropical areas get more than they release, while higher latitudes of the winter hemisphere release more than they receive.

Solar Irradiance

Solar irradiance is the power per unit area received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument. The solar irradiance integrated over time is called solar irradiation, insolation, or solar exposure.

Components Of On Grid Rooftop Solar PV System

• Solar PV Module
• Mounting Array Structure
• Solar Power Conditioning Unit
• Solar Junction Boxes/Connectors
• Solar Cabels,Wires and other Accessories

Solar PV Module

A single solar cell cannot provide required useful output. So to increase output power level of a PV system, it is required to connect number of such PV solar cells. A solar module is normally series connected sufficient number of solar cells to provide required standard output voltage and power. One solar module can be rated to 300 watts. The solar modules or PV modules are commercially available basic building block of a solar electric power generation system.
Actually a single solar PV cell generates very tiny amount that is around 0.1 watt to 2 watts. But it is not practical to use such low power unit as building block of a system. So required number of such cells are combined together to form a practical commercially available solar unit which is known as solar module or PV module.

A single solar cell cannot provide required useful output. So to increase output power level of a

PV system, it is required to connect number of such PV solar cells. A solar module is normally series connected sufficient number of solar cells to provide required standard output voltage and power. One solar module can be rated to 300 watts. The solar modules or PV modules are commercially available basic building block of a solar electric power generation system.
Actually a single solar PV cell generates very tiny amount that is around 0.1 watt to 2 watts. But it is not practical to use such low power unit as building block of a system. So required number of such cells are combined together to form a practical commercially available solar unit which is known as solar module or PV module.

Mounting Array Structure

Photovoltaic mounting systems (also called solar module racking) are used to fix solar panels on surfaces like roofs, building facades, or the ground. These mounting systems generally enable retrofitting of solar panels on roofs or as part of the structure of the building (called BIPV,Building IntegratedPhotoVoltaic).
Solar electric panel arrays are installed in many unique and innovative ways.The objective is a solidly mounted solar panel array that will last for many years and withstand all kinds of weather.

Photovoltaic mounting systems (also called solar module racking)

are used to fix solar panels on surfaces like roofs, building facades, or the ground. These mounting systems generally enable retrofitting of solar panels on roofs or as part of the structure of the building (called BIPV,Building IntegratedPhotoVoltaic).
Solar electric panel arrays are installed in many unique and innovative ways.The objective is a solidly mounted solar panel array that will last for many years and withstand all kinds of weather.

Solar Power Conditioning Unit

A solar grid-tied inverter converts the DC output of PV modules into AC power suitable for transmission on the power grid, or use it for your own consumption, often deploying reactive power to meet new grid codes.
PV Grid Connected Inverters operate at a lower, safer voltage from the PV array, while having the advantages of reliability, Fexibility and improved energy yield. Using lower voltages on the PV side means there are lower voltages in your roof eliminating high voltage hazards and giving peace of mind to installers and service personnel. By using short multiple strings of panels, PV Grid Connected Inverters make sure that there are more paths for electricity to flow, which ensures minimal power loss due to varying environmental or panel conditions.

A solar grid-tied inverter converts the DC output of PV modules into AC power suitable

for transmission on the power grid, or use it for your own consumption, often deploying reactive power to meet new grid codes.
PV Grid Connected Inverters operate at a lower, safer voltage from the PV array, while having the advantages of reliability, Fexibility and improved energy yield. Using lower voltages on the PV side means there are lower voltages in your roof eliminating high voltage hazards and giving peace of mind to installers and service personnel. By using short multiple strings of panels, PV Grid Connected Inverters make sure that there are more paths for electricity to flow, which ensures minimal power loss due to varying environmental or panel conditions.

Solar Junction boxes and connectors

In the Junction boxes, individual module strings are bundled and safely routed to the inverter. It is acombination of an exact, well-organized string monitoring system and a safety concept adapted to the PV technology. The junction boxes will have suitable cable entry points fitted with cable glands of appropriate sizes for both incoming and outgoing cables. They monitor the output of solar PV arrays. These junction boxes are enclosed in an IP 67 rated housing, making it ideal for long term use in PV systems. In addition, the direct connection between the strings and the spring clamp connectors ensures a durable and safe installation.

In the Junction boxes, individual module strings

are bundled and safely routed to the inverter. It is acombination of an exact, well-organized string monitoring system and a safety concept adapted to the PV technology. The junction boxes will have suitable cable entry points fitted with cable glands of appropriate sizes for both incoming and outgoing cables. They monitor the output of solar PV arrays. These junction boxes are enclosed in an IP 67 rated housing, making it ideal for long term use in PV systems. In addition, the direct connection between the strings and the spring clamp connectors ensures a durable and safe installation.

Cables/Wires and other Accessories

The size of the cables between array interconnections, array to junction boxes, junction boxes to PCU etc shall be so selected to keep the voltage drop and losses to the minimum.The bright annealed 99.97% pure bare copper conductors that offer low conductor resistance, they result in lower heating thereby increase in life and savings in power consumption. These wires are insulated with a special grade PVC compound formulated. The skin coloration offers high insulation resistance and long life. Cables are flexible & of annealed electrolytic grade copper conductor and shall confirm to IS 1554/694 1990 and are extremely robust and resist high mechanical load and abrasion. Cable is of high temperature resistance and excellent weatherproofing characteristics which provides a long service life to the cables. The connectors/lugs of copper material with high current capacity and easy mode of assembly are proposed.
Power losses in DC system are due to voltage drop.Stand Alone DC systems typically operate at a lower voltage, 12V, 24V or even 48VDC. Opening and closing while the solar array is under load will lead to arching at the contacts. For reasons as these, the cables are always double insulated and polarized. Cable or Fuses should never be disconnected when under load. Cable from the solar PV modules should follow the shortest route to the array Junction boxes. All Cable are clearly identifiable and connected appropriately, without any clutter to avoid confusion while service and maintenance. This also ensures safety.

The size of the cables between array interconnections,

array to junction boxes, junction boxes to PCU etc shall be so selected to keep the voltage drop and losses to the minimum.The bright annealed 99.97% pure bare copper conductors that offer low conductor resistance, they result in lower heating thereby increase in life and savings in power consumption. These wires are insulated with a special grade PVC compound formulated. The skin coloration offers high insulation resistance and long life. Cables are flexible & of annealed electrolytic grade copper conductor and shall confirm to IS 1554/694 1990 and are extremely robust and resist high mechanical load and abrasion. Cable is of high temperature resistance and excellent weatherproofing characteristics which provides a long service life to the cables. The connectors/lugs of copper material with high current capacity and easy mode of assembly are proposed.
Power losses in DC system are due to voltage drop.Stand Alone DC systems typically operate at a lower voltage, 12V, 24V or even 48VDC. Opening and closing while the solar array is under load will lead to arching at the contacts. For reasons as these, the cables are always double insulated and polarized. Cable or Fuses should never be disconnected when under load. Cable from the solar PV modules should follow the shortest route to the array Junction boxes. All Cable are clearly identifiable and connected appropriately, without any clutter to avoid confusion while service and maintenance. This also ensures safety.