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With over 10 years of expertise in the designing and implementation of off-grid solar systems, TGR Energy is serving lot of properties with installation process.

We have direct relationships with top manufacturers such as Exide, Selectronic, and OutBack Power. Off-grid projects can range from small residential installations to large-scale, automated solar power systems. Origin mining has been a partner in the development of easy-to-use, standalone power stations that can be used as remote monitoring bases.

Off-grid solar systems require high-level knowledge and skill as well as an understanding of the client’s needs. Each project is different, therefore our systems are customized to meet each customer's requirements. TGR Energy guarantees that every system will work flawlessly by getting it right from start.

An incorrectly designed solar power system can cause all kinds of problems for both the end-user as well as the installer. Many systems are simply assembled with "kits" or other off-the-shelf components without proper formulas and values. Unfortunately, most systems are already installed by the time these errors become obvious.

Below are some details to help you understand how off-grid solar systems operate. This will help you compare our quote to other companies.

What is an off-grid solar system?

Also known as stand-alone or off-grid solar systems or standalone solar systems, off-grid systems provide grid-like electricity in areas where grid power is not available or can directly replace unreliable or expensive grid power. Off-grid solar systems include ground- or roof-mounted solar panels, a battery to store energy, an integrated backup generator, and an Inverter/Charger to act as an interface among the various inputs.

TGR Energy can design systems that provide energy for everything from running a refrigerator and TV to providing electricity to an entire island or remote community. TGR Energy designs cutting-edge off-grid Solar Irrigation Systems to pump water.

A diesel generator is usually integrated into larger systems to help in times of high demand or as an emergency backup during periods of severe weather. If the environment permits, other renewable sources such as wind or hydro can also be included.

Modern off-grid technology can be controlled and monitored online, making it much easier to maintain than older systems. Modern off-grid systems also produce high-quality power. This power quality can often be better than average grid electricity and will prolong the life of your appliances and machinery.

Automated and remote systems

Remote and automated off-grid solar systems are what we refer to as "genuine hybrids". They are maintenance-free, can automatically switch on pumps or backup generators when required.

Off-grid solar systems - autonomy

Professionals recommend that you have at least 1.5 to 2 days of autonomy in your battery bank when designing an off-grid system. This is only if there is a backup generator. The "autonomy time" should be extended to 2-3 days if there is no generator.

The autonomy time refers to the average daily usage times. It means that even in low or no sun during poor weather, there will be enough power to continue to use all of your appliances without the need for a generator.

You can calculate the size of your battery bank by multiplying your daily kWh consumption by the number of days you want to have autonomy. If you need 2 days of autonomy and you use 10kWh per week, you will need a battery bank with 20kWh.


Modern Gel and AGM batteries can be recharged with either water or acid and are extremely efficient. The Lithium-ion battery is a high-performance and more expensive alternative to traditional energy storage that is rapidly gaining popularity around the world.

Your battery bank's usable storage is the number of kWh that you can drain from your batteries before they reach a certain point of discharge. The DOD (depth of discharge) is the main factor that determines how long your batteries can last before they start losing power. A recommended DOD level is between 30-40%, which means that we only take out 30%-40% from the total energy stored in your batteries.

Sonnenschein A602 batteries are a good choice. They last between 4500-5500 cycles without deterioration. The battery will slowly start to store less power. The battery does not cease to work from one day to the other. Instead, it slowly loses capacity. This type of battery can last up to 15 years depending on its usage. The American Absolute is recommended for applications that require high discharge rates and rapid charge rates. They are maintenance-free and heavy-duty AGM batteries. Although their life span is slightly shorter than the Gel Sonnenschein, they offer many other benefits. The mounting rack that the batteries come in saves space and allows for easy storage.

The battery bank's life cycle and health will be improved by using a high-quality battery management unit and charger, such as the Selectronic. We can create systems that will save up to half of the battery's cost if required.



We also want to talk about the "C" rating of a battery bank. The total storage capacity of a battery in Amps is called the C rating. C100 ratings are usually a standard rating for batteries. The C100 rating is only applicable if the battery is being discharged for more than 100 hours. This would not apply in an off-grid situation. The correct rating would be C10 (discharge rate greater than 10 hours).

The storage capacity of batteries decreases the faster they are discharged. Therefore, it is crucial to use the correct "C" rating for storage calculations.

It is a common industry practice to allow at least 10% loss in conversion from AC (alternating current), used in homes, to DC (direct current), and DC back to AC.

Many solar companies neglect to account for conversion losses and the correct "C" rating when designing off-grid systems. It could be that it makes the battery bank appear smaller, which can reduce the proposal's maximum value and make it more ambitious. This could be because these companies don't have the right knowledge to design off-grid solar systems correctly.

This information is misleading and could lead to large price differences between systems. It is ultimately you, the customer who will discover the hard way whether the company selling the system was knowledgeable or trying to sell the system quickly.



You may not be aware of the differences between AC and DC coupled systems depending on how much research you have done into the off-grid solar systems. A DC-coupled system is where the energy flows from the panels through an MPPT charger controller, and then into the battery. An AC inverter connects to the battery. It takes stored power from the bank and supplies 240v AC power when it is needed.

AC-coupled systems have an AC inverter, which is almost like a standard grid-connected inverter. This will convert the DC power from solar panels into AC power. It will cover all the electrical loads within the home or business directly without the need to use the batteries. This drastically reduces battery usage.

The bi-directional charger, also known as Inverter-Charger (such as the Selectronic SPPRO), is used to charge the batteries and then discharge them. This bi-directional charger controls the AC inverters as well as manages the whole off-grid system. It can automatically start or stop the generator depending on its configuration.

AC coupled systems have lower conversion losses because power doesn't need to be sent through the battery bank first. The battery bank would be sufficient to power the system at night.

A DC-coupled solar system reduces conversion losses by flowing energy directly into the batteries and charging them.

We often combine both AC inverters with DC chargers to get the most out of both. The DC side charges the batteries at night with minimal losses and the AC side charges your load during the day with little loss. This is a key advantage of TGR Energy over its competitors, with over a 10% gain.


Our preferred equipment for off-grid projects

OutBack Power equipment is a North American brand that is known for its reliability in harsh environments. It's ideal for smaller systems of up to 5kW. Electronic products are made in Australia for larger off-grid systems. Many of our off-grid systems use the Imark MPPT Chargers and Shunt regulators. They are made in Melbourne and Brisbane. We have witnessed the exceptional performance and quality of this component firsthand. AERL has won numerous national awards for its DC Charger's efficiency.

Installation and Beyond

Our dedicated engineers will design your project. They are available seven days a săptămână, from the initial quote process to the handover of your system. One of our skilled Electricians will complete the installation. The Selectronic SP PRO unit is connected to the battery bank, the generator, and your house loads by our Electrician. The SP-PRO can charge your batteries and draw stored energy from them when needed, even if it is cloudy.

The SP-PRO's load side is typically connected to your main switchboard, which we can supply and install if necessary. As with all grid-connected solar systems, the AC Solar inverters are connected to your main switchboard. Only the difference is that inverters and SP-PRO can talk to one another via RS485 network cables. The SP-PRO will know how much power your system is using at the moment, how long it needs to charge its batteries, and how much power the solar inverters are generating. The SP-PRO will turn on the generator if your load exceeds the solar panels' capacity.

If your batteries are fully charged and your solar inverters are producing more power than your loads, the SP-PRO will inform the solar inverter that it should produce less power. This can be seen on your home display. You can then turn on additional loads if it happens during the day.

Our off-grid solar systems are generally fully automated and can be easily monitored locally. Online monitoring is possible, but you will need an ADSL or other hard-wired internet connection.

TGR Energy's standard procedure includes the monitoring of your solar system for the first 4-6 weeks to ensure that it is functioning properly and we can adjust it to meet your needs.


TGR Energy is an accredited Selectronic integrator. This is beneficial to all our customers because their standard five-year warranty is automatically extended up to seven years.