Yash
Kelwon has come up with an innovative Li-ion inverter than can be solar-powered.
It is a leading Korean brand of electronics consumer products.
This lithium-integrated inverter suits your modern lifestyle and can provide you with uninterrupted power.
So let us discuss more it in this post.
Kelwon models and their Price
The Kelwon inverter price starts from ₹ 49,990/- and goes up to ₹ 4,99,900/- .
- 1 kW: ₹ 49,990/- (including GST)
- 2 kW: ₹ 79,990/- (including GST)
- 3 kW: ₹ 1,49,990/- (including GST)
- 5 kW: ₹ 2,99,900 (including GST)
- 10 kW: ₹ 4,99,900/- (including GST)
Kelwon Features
Kelwon Li-ion inverter comes with many features. Let us discuss some of them.
(i) Compact, Portable, and Wall mounted
We see conventional inverter batteries. These are heavy and bulky and occupy large spaces. The Kelwon Li-ion inverter is compact, can be placed anywhere, and mounted on the wall. Thus, saving space that you can utilize for other purposes.
(ii) Lithium Iron Phosphate battery
- This compact machine has an in-built LiPo 4 Gr battery. Let me give you a brief of this battery. Any battery has 2 electrodes (one is called a cathode and the second one is an anode), an electrolyte, and a separator.
When the battery is connected to the load.
The electrolyte acts as a transmitter. It transmits positively charged lithium ions from the anode to the cathode.
This movement of lithium ions creates free electrons in the anode.
And these electrons constitute an electric current which is then passed through the load.
In this way, the chemical energy stored in the battery gets converted into electric current.
The lithium phosphate battery is small and lightweight.
Moreover, the in-built integrated electronic circuit protects it from overcharging and heating.
- Lithium phosphate batteries are more immune to thermal stress. This makes them safer to use.
- It is because of its construction and the constituents used, this battery requires minimal maintenance.
(iii) Pure Sine wave Inverter
The Kelwon Li-ion inverter produces a pure sine wave to run the electrical appliances. The pure sine waveform has many benefits over the over waveforms.
You know that our electrical appliances are designed for pure sine waveform.
I mean, they work to their best when pure sine waveform is fed as an input.
This improves their useful life
When the grid supply goes down and your fan is running on a conventional inverter-battery system. You might have observed that the fan starts producing sound. This is due to the inverter not producing pure sinewave.
The Kelwon Li-ion inverter produces a pure sine waveform that makes the operation of the electrical appliances quiet and smooth.
As the waveform produced by Kelwon inverter is in resonance with the electrical appliances. Most of the energy gets converted into useful work. Hence, the heat losses are minimized.
The above 2 benefits improve the useful life of the appliances and this saves you money on their maintenance.
(iv) Other Features
- Kelwon offers 60 months Inverter warranty and 60 months battery warranty.
- It can easily be Solar powered and one can enjoy n and smooth solar electricity.
- The Kelwon Li-ion inverter auto-restarts while the AC is recovering.
- It also has a provision for Overload, Over temperature, and short-circuit protection.
- The battery life cycle is 15 years.
Kelwon Specifications
Let us see some of the important specifications of Kelwon Li-ion inverter series.
You can see that Kelwon offers its inverters under 5 power ratings namely:
- 1000 VA
- 2000 VA
- 3000 VA
- 5000 VA
- 10000 VA
We can say that it caters the energy needs of users from small to large segments.
The maximum solar power array for different series is shown in the table.
It indicates the maximum power of solar panels with which the particular series of Kelwon inverters is compatible.
For example, under the 2000 VA series, the 1340 watts solar panels can effectively charge the battery and can run the electrical appliances.
You can also see that for power ratings below 5000 VA, it uses PWM solar charge controller while for higher power ratings it has MPPT solar charge controller.
Why there is a difference in the type of charge controller?
You will learn about this later in the post.
The charging time of the battery using solar is also mentioned in the chart above.
It is in between 4 to 7 hours.
Kindly look at the battery voltages also.
When you are planning to charge your inverter battery with solar.
The battery voltage should not be neglected.
One should configure the solar panels in a way that the system voltage is always higher than the battery voltage.
Then only the battery will be charged from the solar panels.
The battery capacity shows the amount of charge it can store. More charge or AH means your battery can run the electrical appliances for a longer time.
Solar and Kelwon Inverter
The Kelwon li-ion inverter is compatible with both Solar and Grid.
When you decide to go Solar and use Kelwon Li-ion inverter as one of the components.
It becomes important to first understand the working of the basic solar power system.
(a) The basic solar power system
The basic solar power system with battery backup looks something like this shown below:
The solar panels absorb the sunlight and convert it into electricity.
Thereafter it goes into the charge controller, battery, and inverter.
And finally, runs your electrical appliances.
Let us understand the functioning of these components.
The solar charge controller
The solar charge controller connects the solar panels to the battery.
It plays a very important role in the system.
- The solar charge controller regulates the charging of the battery.
Okay, let me explain it more.
The solar panels produce current in the daytime.
This current goes into the battery but through the solar charge controller.
When the charge controller sees that the battery is near to empty, it allows the full flow of the current to go inside the battery.
And
When the battery is near full, it passes only a small current to the battery.
And
When the battery is fully charged, it allows trickle of the current so that it remains fully charged.
- The solar charge controller prevents the backflow of the current to the solar panels at the night.
During the day, the solar panels charge the battery.
At the night, they are not producing current.
While the battery is charged.
Now, the battery is at a higher potential as compared to solar panels.
We all know the current flows from higher to lower potential.
And
This opposite flow of the current might damage the solar panels and also drain the battery.
But the solar charge controller in between the solar panels and the battery prevents this backflow.
The Battery
The output of the charge controller goes inside the battery.
It absorbs this energy and stores it in the form of chemical energy (a kind of potential energy).
The output of the battery is connected to the inverter.
Whenever energy is required to run the electrical appliances.
The inverter withdraws from the battery.
The chemical energy stored in the battery gets converted into electricity and goes inside the inverter.
The Inverter
The electrical energy from the battery is in Direct Current form.
But our electrical appliances run on Alternating current.
We need a system that can do this conversion (DC to AC)
The inverter does this job.
It takes the direct current from the battery and converts it into Alternating Current.
Hence run the electrical appliances.
I am sure that you have understood the functions of these components used in the solar power system.
In the conventional solar power system, you need to connect each component separately.
But in Kelwon Li-ion inverter, these 3 components (the solar charge controller, Li-ion battery, and the inverter) are integrated together into one compact design.
Just connect the solar panels with the Kelwon li-ion inverter and the system is ready to power your electrical appliances.
Types of solar charge controllers in Kelwon Li-ion inverter
We saw in the table above that Kelwon uses PWM solar charge controller for low power rating inverters such as 1 kVA, 2kVA, and 3kVA.
While the higher power rating inverters such as 5 kVA and 10 kVA have MPPT solar charge controllers integrated into them.
PWM vs MPPT
You might be wondering why this is so and what are PWM and MPPT solar charge controllers.
Let us get a basic idea about them.
Both types of charge controllers are based on sophisticated technologies.
And they adjust the charging rate based on the charging condition of the battery.
But the MPPT charge controller does one thing extra.
Let us understand with the help of an example.
Assuming your solar panels are at 36 volts and producing 7 amperes current.
While the battery voltage is 12 volts.
The PWM solar charge controller placed in between the battery and the solar panels brings down the voltage neat to 12 volts and then starts charging the battery.
This scenario can be mathematically represented as:
The power produced by solar panels= 36 volts x 7 amp
= 250 watts
The power is given to the battery = 12 volts x 7 amperes
= 84 watts
166 watts (250 watts – 84 watts ) are not used for charging the battery.
Hence wasted by the PWM solar charge controller.
MPPT Working
While on the other hand, the MPPT charge controller works smartly.
It notices this wide voltage difference and converts this into an equivalent current value so that the input and output power of the MPPT charge controller remains the same.
It does in this way;
Power from solar panels
36 volts x 7 Amp ≈ 250 watts (I have rounded off the value)
Power goes into the battery through MPPT solar charge controller
12 volts x 21 Ampere ≈ 250 watts
(Although the voltage comes down the current is increased by an equivalent amount. So that the power remains the same).
The input and the output power are the same.
Hence no power is wasted in this process.
It does not mean that PWM solar charge controllers are inferior to MPPT ones.
Each works effectively depending on the situation.
PWM solar charge controllers are affordable and work best when the system size is small and the system voltage and the battery voltage are the same.
(It is not actually the same, the solar panel voltage has to be higher than the battery voltage. Then only it can charge the battery. We can say that PWM works best when the voltage difference is small).
Hence, Kelwon uses PWM solar charge controller for its inverters under 5 kVA.
The MPPT solar charge controllers work best when the system sizes are large.
Thereby, you see MPPT charge controllers in the higher power ratings of Kelwon li-ion inverters.
There are times when you cannot avoid the wide voltage difference between the system and the battery. Here also MPPT is preferred over PWM.
They are also preferred in regions where the sunlight intensity is low and have cold climates.
Conventional Battery Inverter vs Kelwon Li-ion Inverter
The Kelwon Li-ion inverter price is almost double the conventional battery inverter price.
But
Its benefits are more than the price difference between the two.
Why one should use solar power for charging the Kelwon Li-ion inverter?
You have the option of connecting Kelwon inverter either with Solar or Grid.
If given the choice, I would prefer using Solar.
I can list a number of reasons for that. Let me give you a few of the most important ones.
Increasing Grid Prices
The average price of grid electricity in India is 6.6 per unit. And it is increasing at an average of 8% per year.
If you are powering Kelwon inverter with the grid.
The cost of doing so would increase by 8% per year.
If I calculate the per unit grid rate in the 25th year. Then it would be Rs. 45 per unit.
It means the cost of charging per unit would be Rs. 45.
Solar is clean and affordable
While on the other hand, Solar is a clean and affordable energy solution. In the last 10 years, its prices have declined by more than 70%.
Today, we see solar panels coming with the latest technologies such as Half-cut solar cell technology, Bi-facial solar panels, Mono-PERC solar panels, and more development going on. All these technologies have minimized the losses in solar panels and made them more efficient than ever.
Using solar mitigates carbon emissions
Another benefit of using solar is that it mitigates carbon emissions from the air. In India over 70% of energy needs are fuelled by burning coal. Therefore, there is a 70% chance that your grid is feeding current through coal burning.
And
Burning of 1 kg of coal releases 2.4 kg of carbon emissions into the air.
These carbon emissions are responsible for climate change.
By using solar for powering Kelwon Li-ion inverter, you contribute towards preserving the environment.
A 5-kW solar power system in India can mitigate over 7 tonnes of carbon emissions from the air.
Conclusion
Kelwon Li-ion inverter is the latest technology compact inverter.
It works with both grid and solar.
Its compact size and lightweight give users the flexibility to take and place it anywhere.
It can be used in places with limited spaces.
Kelwon has rightly used PWM and MPPT charge controllers in its series.
PWM works well with a lower power rating.
It also makes it affordable.
While MPPT suits a higher power rating inverter.
Although it is priced higher than the conventional inverter-lead acid battery.
But its benefits are far more than the user gets in the long run.
Using Kelwon Inverter with Solar offers you benefits in the long run.
