Solar Roof top PV & Solar Ground Mounted PV systems

SUNGREEN strongly believes in the sun’s potential to significantly address the problems associated with power obtained from non-renewable sources of energy. It is with this passion that we aim to work and provide solar solutions to our customers. Quality has always been of utmost priority for SUNGREEN, and with this drive we challenge ourselves to provide the same in the most cost effective manner. SUNGREEN takes on charge and commitment towards development of eco-friendly technologies with innovative and futuristic energy solution. We, at SUNGREEN, recognize the importance of every step taken towards to building a greener and safer future. By harnessing the inexhaustible energy of Sun, SUNGREEN offers efficient and advanced solutions for energy requirements for today and tomorrow.

SUNGREEN provides turnkey EPC solar energy solutions from concept to commissioning for solar PV and also operation and maintenance services throughout the lifetime of the project. Led by visionary leader and industry veterans, SUNGREEN provides end-to-end solutions including engineering, procurement and construction (EPC) services for our customers seeking to build photovoltaic solar power plants. Our expertise and experience gathered from executing solar PV plants across various terrains and regions of India hold us in good stead to provide world-class project management services that provides the shortest gestation time-period to complete our projects without any compromise on the quality. Solar Power Plants executed by us rank amongst the highest generation PV plants in India with consistently high Plant Performance Ratios throughout the year.

Grid-Tied, On-Grid, Utility-Interactive, Grid Intertie and Grid Backfeeding are all terms used to describe the same concept - a solar system that is connected to the utility power grid. When the solar system generates excess electricity, the excess electricity generated is exported to the Grid and during requirement, Electricity is imported from the Grid. Customers can choose between "Gross" & "Net" metering for the same.

Advantages of Grid-Tied System 1. Save more money with net metering

A grid-connection will allow you to save more money with solar panels through better efficiency rates, net metering, plus lower equipment and installation costs:

Batteries, and other stand-alone equipment, are required for a fully functional off-grid solar system and add to costs as well as maintenance. Grid-tied solar systems are therefore generally cheaper and simpler to install.

Your solar panels will often generate more electricity than what you are capable of consuming. With net metering, homeowners can put this excess electricity onto the utility grid instead of storing it themselves with batteries.

Net metering (or feed-in tariff schemes in some countries) play an important role in how solar power is incentivized. Without it, residential solar systems would be much less feasible from a financial point of view.

Many utility companies are committed to buying electricity from homeowners at the same rate as they sell it themselves.

2. The utility grid is a virtual battery

Electricity has to be spent in real time. However, it can be temporarily stored as other forms of energy (e.g. chemical energy in batteries). Energy storage typically comes with significant losses.

The electric power grid is in many ways also a battery, without the need for maintenance or replacements, and with much better efficiency rates. In other words, more electricity (and more money) goes to waste with conventional battery systems.

Lead-acid batteries, which are commonly used with solar panels, are only 80-90% efficient at storing energy, and their performance degrades with time.

Additional perks of being grid-tied include access to backup power from the utility grid (in case your solar system stop generating electricity for one reason or another). At the same time you help to mitigate the utility company`s peak load. As a result, the efficiency of our electrical system as a whole goes up.

Equipment for Grid-Tied Solar Systems

There are a few key differences between the equipment needed for grid-tied, off-grid and hybrid solar systems. Standard grid-tied solar systems rely on the following components:

  • Grid-Tie Inverter (GTI) or Micro-Inverters
  • Power Meter (Net or Gross)
Grid-Tie Inverter (GTI)

What is the job of a solar inverter? They regulate the voltage and current received from your solar panels. Direct current (DC) from your solar panels is converted into alternating current (AC), which is the type of current that is utilized by the majority of electrical appliances.

In addition to this, grid-tie inverters, also known as grid-interactive or synchronous inverters, synchronize the phase and frequency of the current to fit the utility grid. The output voltage is also adjusted slightly higher than the grid voltage in order for excess electricity to flow outwards to the grid.


Micro-inverters go on the back of each solar panel, as opposed to one central inverter that typically takes on the entire solar array.

There has recently been a lot of debate on whether micro-inverters are better than central (string) inverters.

Micro-inverters are certainly more expensive, but in many cases yield higher efficiency rates. Homeowners who are suspect to shading issues should definitely look into if micro-inverters are better in their situation.

Power Meter

Most homeowners will need to replace their current power meter with one that is compatible with net metering. This device, often called a net meter or a two-way meter, is capable of measuring power going in both directions, from the grid to your house and vice versa.


In this system, you have a single new bi-directional meter. When you consume electricity from the grid (or your electricity supply), the meter readings will move forward; but, when you produce electricity and sent it to the grid, the meter readings shall move backward. Suppose you use 10 units of electricity in a day and produce 8 unites, your meter will show a reading of 2 units. And if you use 10 units of electricity and produce 12 units, then your meter will show - 2 units. Your bill at the ned of month will be based on net units consumed/produced. If you generate extra electricity in any month, the surplus is carried over to the next month and netted. At the end of a year, if your total production is more that what you consumed, then you consumed, then you will get paid for the next surplus electricity produced at the cost dicided by your state’s electricity reculatory commission.


In this system, there are two meters: one measures your electricity consumption and the other measures your electricity production. Consequently, you get two different bills: one for consumption and other for production. There is no change in the way your consumption is billed (as it happens today), but you get paid separately for the electricity you produce. Again, the cost of electricity that you are paid is desided by the states’s electricity regulartory commission.

How do the two differ?

If you look at the way electricity is priced (check domestic tariff slabs), the price of electricity is lower when consumption is less and it is higher when the consumption is more. When you 'net' your consumption, you don't get a fixed cost for your electricity production. The price that you get varies, based on your consumption/production, whereas in case of Gross Metering, you get a fixed price for all the electricity you produce.

How do the two differ?

If you look at the way electricity is priced (check domestic tariff slabs), the price of electricity is lower when consumption is less and it is higher when the consumption is more. When you 'net' your consumption, you don't get a fixed cost for your electricity production. The price that you get varies, based on your consumption/production, whereas in case of Gross Metering, you get a fixed price for all the electricity you produce.

Is Grid ConnectedSystem Goodfor Everyone?

Although the policy is now available in most states in India, but if you reside in a location which experience a lot of power cuts, then a “Grid Connected” system is NOT good for you. The reason is - when you have a “Grid Connected” system, you have to put all the electricity that you produce onto the grid. But during power cuts, you essentially get disconnected from the grid, which is why your system should NOT put electricity on the grid. On such occasions, you need a battery backup to store the electricity that you generate.

Before implementing a solution, you need to assess your power cuts and accordingly decide if putting a “Grid Connected” system works for you or not. Because if power cuts are long and frequent, you would either waste electricity or you would have to figure out a way to store it in batteries.

An off-grid solar system (off-the-grid, standalone) is the obvious alternative to one that is grid-tied. For homeowners that have access to the grid, off-grid solar systems are usually out of question. Here's why:

To ensure access to electricity at all times, off-grid solar systems require battery storage and a backup generator (if you live off-the-grid). On top of this, a battery bank typically needs to be replaced after 5/10 years. Batteries are complicated, expensive and decrease overall system efficiency.

Advantages of Off-Grid Solar Systems 1. No access to the utility grid

Off-grid solar systems can be cheaper than extending power lines in certain remote areas.

Consider off-gird if you’re more than 100 yards from the grid.

2. Become energy self-sufficient

Living off the grid and being self-sufficient feels good. For some people, this feeling feeling is worth more than saving money. Energy self-sufficiency is also a form of security. Power failures on the utility grid do not affect off-grid solar systems.

On the flip side, batteries can only store a certain amount of energy, and during cloudy times, being connected to the grid is actually where the security is. You should install a backup generator to be prepared for these kinds of situations.

Equipment for Off-Grid Solar Systems

Typical off-grid solar systems require the following extra components:

  • Solar Charge Controller
  • Battery Bank
  • DC Disconnect (additional)
  • Off-Grid Inverter
  • Backup Generator (optional)
Solar Charge Controller

Solar charge controllers are also known as charge regulators or just battery regulators. The last term is probably the best to describe what this device actually does: Solar battery chargers limit the rate of current being delivered to the battery bank and protect the batteries from overcharging.

Good charge controllers are crucial for keeping the batteries healthy, which ensures the lifetime of a battery bank is maximized. If you have a battery-based inverter, chances are that the charge controller is integrated.

Battery Bank

Without a battery bank (or a generator) it’ll be lights out by sunset. A battery bank is essentially a group of batteries wired together.

DC Disconnect Switch

AC and DC safety disconnects are required for all solar systems. For off-grid solar systems, one additional DC disconnect is installed between the battery bank and the off-grid inverter. It is used to switch off the current flowing between these components. This is important for maintenance, troubleshooting and protection against electrical fires.

Off-Grid Inverter

You will need an inverter to convert DC to AC for all other electrical appliances.

Off-grid inverters do not have to match phase with the utility sine wave as opposed to grid-tie inverters. Electrical current flows from the solar panels through the solar charge controller and the bank battery bank before it is finally converted into AC by the off-grid-inverter.

Backup Generator

It takes a lot of money and big batteries to prepare for several consecutive days without the sun shining (or access to the grid). This is where backup generators come in.

In most cases, installing a backup generator that runs on diesel is a better choice than investing in an oversized battery bank that seldom gets to operate at it`s full potential. Generators can run on propane, petroleum, gasoline and many other fuel types.

Backup generators typically output AC, which can be sent through the inverter for direct use, or it can be converted into DC for battery storage.

Hybrid solar systems combines the best from grid-tied and off-grid solar systems. These systems can either be described as off-grid solar with utility backup power, or grid-tied solar with extra battery storage.

If you own a grid-tied solar system and drive a vehicle that runs on electricity, you already kind of have a hybrid setup. The electrical vehicle is really just a battery with wheels.

Advantages of Hybrid Solar Systems 1. Less expensive than off-gird solar systems

Hybrid solar systems are less expensive than off-grid solar systems. You don`t really need a backup generator, and the capacity of your battery bank can be downsized. Off-peak electricity from the utility company is cheaper than diesel.

2. Smart solar holds a lot of promise

The introduction of hybrid solar systems has opened up for many interesting innovations. New inverters let homeowners take advantage of changes in the utility electricity rates throughout the day.

Solar panels happen to output the most electrical power at noon – not long before the price of electricity peaks. Your home and electrical vehicle can be programmed to consume power during off-peak hours (or from your solar panels).

Consequently, you can temporarily store whatever excess electricity your solar panels in batteries, and put it on the utility grid when you are paid the most for every kWh.

Smart solar holds a lot of promise. The concept will become increasingly important as we transition towards the smart grid in the coming years.

Equipment for Hybrid Solar Systems

Typical hybrid solar systems are based on the following additional components:

  • Charge Controller
  • Battery Bank
  • DC Disconnect (additional))
  • Battery-Based Grid-Tie Inverter
  • Power Meter
Battery-Based Grid-Tie Inverter

Hybrid solar systems utilize batter-based grid-tie inverters. These devices combine can draw electrical power to and from battery banks, as well as synchronize with the utility grid.

On Grid

As the name suggests, grid tied systems are always connected to the grid. The energy that your solar panels produce is fed to the grid.

During times when there is no sunlight, your loads consume the grid’s electricity. In a grid tied system, there is no necessity for a battery to store electrical energy. Here the grid serves as the storage of your solar energy.

  • As it does not require battery banks and other standalone components, it is relatively cheaper than Off-Grid or hybrid system.
  • It facilitates you to take advantage of net metering. Any extra electricity that you produce can be sold back to the utility. This means that by the end of the month, you only pay for the net kWH electricity used.
  • Since you do not have a battery bank, you can’t store electricity the Grid is a virtual storage. If during the right, your grid is down, you will not have any electricity.
  • monthly fees that you’ll need to pay.
Off Grid

Off grid solar systems or standalone systems are not connected to the Grid. The solar panels produce electricity, which is stored in the battery banks. During nights this electricity is used to provide power.

This is the only alternative when you live in a remote area where there is no electricity and you do not have grid access.

  • Only option if you live in a remote area with no grid access
  • Feeling of being self-sufficient for your energy demands is great
  • Grid failures and downtime won’t affect your power supply
  • The additional costs of installing a battery bank, and in some cases an alternative source of power like a diesel generator, makes these systems more expensive than a grid tied system.
  • Standalone systems have more components and therefore need more maintenance. Especially the batteries need regular care.
  • Replacement of battery banks is another problem. Battery banks are designed to last for 7-10 years after which they need to be replaced this is a cost that you need to take into account.
Solar Hybrid

Hybrid Solar systems can be called the best of both worlds. They are also referred to as Off Grid Solar systems with an option of utility backup.

One configuration of this system requires you to have a disconnect switch which you could toggle on or off depending upon your electricity requirements. Usually this is an automatic switch.

  • You can switch between power from the grid or power from your battery bank at you own will.
  • Less expensive than a completsstand alone system, as there is no need for a backup generator. The possibility to connect to the grid serves as the backup power.
  • Availability of the grid means that you can likely downsize your battery bank capacity.
  • Less maintenance and higher reliability IF the grid is reliable.
  • Cannot be used in remote areas where there is no grid power.