Planning a rooftop solar setup

@adder @rdst_1

I was looking into this further to get options available for my setup. Here is some components and data I came across...
(As you guys pointed out I will stick to 5kw for now)

1) Found a few other hybrid inverters which support both high and low voltage batteries. Growatt - Low / High, Huayu - this is marketed as Cellcronic (Galaxy 6G), there are some videos on Youtube explaining its features. They allow you to use lithium or lead acid batteries, select the max grid feed and have a 5/10 year warranty. Have contacted Growatt distributor to know if they can import a specific model for a few users.

The celletronic ones appears to be clones of voltronics, not genuine voltronics. Their Galaxy 6g is deya china rebadged it costs $1600 in aliexpress. The other model they have is listed at 85k or so but its not MNRE approved and it costs $580 basically we are paying nearly double the price.

2) A company Hykon from Kerala assembles LiFePO4 batteries in India. They've launched SAFE series of batteries which cost 31K for 100Ah, about 50% higher than Exide Solatron batteries which are the best lead acid ones. Cells used internally are mentioned and have 5 year warranty. Pricing is better than Vison Mechatronics.

There are lot of suppliers for battery in bangalore itself. As said earlier in bangalore you can get a 12v 100ah equivalent for 18k+GST, price is just for cells without BMS and wrapping or casing.

3)BiFacial solar module from Vikram and Waree rated at 400w for front which can go up to 480w are available for 8-9K in the market. These can be useful for folks with less rooftop space.
Panels which are bifacial, the other side only works if there is sufficient reflection from roof, in reality the amount of light you can get from the other side is very less, they also do not have a aluminium bezel and it requires special mounts, since they are not standard sizes in bi facial, the extra price overall is not worth it. More over because they lack the aluminium bezel, heavy winds can cause stress in the glass.

4) Enphase micro inverters price has come down to 7K for 'IQ 7+'. Apparently some new Chinese hoymiles micro inverters are available in India as well, with 12 year warranty, have 2 - 4 MPTTs and can be used with 2-5 panels depending on the wattage. Huayu ones are apparently available in India as well.
About inverter warranty we don't even know the distributor will be in business in 5 years time. Unlike panels which are made in India and not dependent on china. Inverters warranty is entirely based on india china relations and the distributor vs the chinese company relation. Most of the time inverter manufacturers will find every excuse to deny warranty.
I heard in solar expo from one guy who stopped dealing with growatt due to poor support, whether its BS or reality is a different question.

On grid inverters made by indian companies do exist like luminous



Look for inverters that are non chinese, if you want warranty. My flin fusion is made in china but designed in Taiwan.
5) Cost of 5kVA external battery inverter, in Bangalore, is approximately 30K, 3.5kVA is approximately 15K
Those inverters needs another MPPT charge controller to charge batteries, otherwise they consume around 50w to 100w/hr just to keep the batteries fully charged. Also regarding the VA rating, 5000va inverter could in reality be just 3500w to 4000w, not necessarily 5000w.
anyone have experience of vispra inverters?
prices are at par,
made in india ( chennai )
They are just regular inverter with a PWM controller and of low capacity nor can they use solar and utility simultaneously, this inverter works entirely by battery, the solar charger only keeps charging the battery and the inverter section runs off it. It cannot power loads directly via solar or without batteries.
 
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Panels which are bifacial, the other side only works if there is sufficient reflection from roof, in reality the amount of light you can get from the other side is very less, they also do not have a aluminium bezel and it requires special mounts, since they are not standard sizes in bi facial, the extra price overall is not worth it. More over because they lack the aluminium bezel, heavy winds can cause stress in the glass.
Are you sure about this, because Vikram and Waaree both seem to have framed half cut ones which are approximately the same size as 72 cell panels.

About inverter warranty we don't even know the distributor will be in business in 5 years time.
Enphase and SolarEdge are large US companies with worldwide presence, so they would be around I guess. Agree on the Chinese companies though.

There are lot of suppliers for battery in bangalore itself. As said earlier in bangalore you can get a 12v 100ah equivalent for 18k+GST, price is just for cells without BMS and wrapping or casing.
Could you please share names of some which you found reasonable / interesting / have contacted in the past ?
 
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Are you sure about this, because Vikram and Waaree both seem to have framed half cut ones which are approximately the same size as 72 cell panels.


Enphase and SolarEdgeare large US companies with worldwide presence, so they would be around I guess. Agree on the Chinese companies though.


Could you please share names of some which you found reasonable / interesting / have contacted in the past ?
Unless they are transparent, how will sunlight pass through them for reflection, the half cell ones come with frame and the amount of light it can pass through the gaps in questionable.
It works well in open land, when in sunrise or sunset, when you have adequate spacing. Or in Snow filled ares where the white snow reflects.

Search for solmitra, there was another company as well cannot recall, will see if I can find the visting card. But basically Solmitra was the one who gave a quote of roughly 18k+gst for 12.8v 100ah lifpo4 battery excludes the price of BMS, wrapping or case.
 
Unless they are transparent, how will sunlight pass through them for reflection, the half cell ones come with frame and the amount of light it can pass through the gaps in questionable.
We anyway have to get a structure fabricated to install solar at our place due to tall trees around. Thinking of getting something like this. Hope it won't be too expensive. That'll allow some gardening activity on the roof as well.
 
We anyway have to get a structure fabricated to install solar at our place due to tall trees around. Thinking of getting something like this. Hope it won't be too expensive. That'll allow some gardening activity on the roof as well.
Those are Z channels not used in home size installs, its mostly used in warehouses/factory size construction.
If you have trees you need to keep a note on the shadows created by trees and neighboring buildings, I studied the shadow for the entire 12 months to get a idea about how many panels, I can put and where to put them. In summer I could put little over 15kw of panels but in December I can utilize only 7kw of panels, rest of them will be in shadow due to a iron sheet structure in the building next to mine. This year the structure was removed by the vacating tenants of that building, so now I am tracking the shadow every 10 days.
 
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Those are Z channels not used in home size installs, its mostly used in warehouses/factory size construction.
If you have trees you need to keep a note on the shadows created by trees and neighboring buildings, I studied the shadow for the entire 12 months to get a idea about how many panels, I can put and where to put them. In summer I could put little over 15kw of panels but in december I can utilizd only put 7kw of panels, rest of them will be in shadow due to a iron sheet structure in the building next to mine. This year the structure was removed by vacating tenants of that building, so I am tracking the shadow every 10 days.
Thanks. I need to do even more reading I suppose.

Few questions I had regarding batteries -
1) It appears 24 & 48v lithium batteries are exponentially more costly than 12v ones, for the same Ah. Any specific reason for this ?
2) Can I chain 4 12v lithium batteries and connect them to my inverter / ups, similar to lead acid batteries or is it different for lithium ?
3) Do you know any hybrid inverters available in India that work with lithium batteries ? Does FlinFusion support it ?
 
Thanks. I need to do even more reading I suppose.

Few questions I had regarding batteries -
1) It appears 24 & 48v lithium batteries are exponentially more costly than 12v ones, for the same Ah. Any specific reason for this ?
2) Can I chain 4 12v lithium batteries and connect them to my inverter / ups, similar to lead acid batteries or is it different for lithium ?
3) Do you know any hybrid inverters available in India that work with lithium batteries ? Does FlinFusion support it ?
1) The only reason if it may is due to larger BMS, bigger case, more wiring internally. But when in terms of off the shelf bill of material for DIY method, i expect the price to increase by max of 3 to 4k.

2) Yes you can provided each of the pack has its BMS. Infact a 12v lithium battery has 4 cells wired in series ifs its a lifep04 pack and about 3 cells in series if its a li-on version.

3) Any flin energy inverter will work with lithium, the difference being is that a dedicated inverter with lithium settings will communicate with the battery via CAN port and will stop charging when the battery reaches 100%. If it doesn't have a CAN port or any other communication method the inverter will rely on voltage of the pack, once it reaches the user set voltage, it will ramp down the amps, In the case of flin fusion it can go as lower then 0.49A (possibly even less but my meter cannot measure below 0.5amps) in this case the passive BMS or active BMS of the battery will just convert the .5A which is = to 24watt of energy for a 48v pack into heat via a resistor bank of the BMS and people have been doing this for ages, 24watts (again flin could be even lower) for a 5000w solar array is minuscule.
 
They are just regular inverter with a PWM controller and of low capacity nor can they use solar and utility simultaneously, this inverter works entirely by battery, the solar charger only keeps charging the battery and the inverter section runs off it. It cannot power loads directly via solar or without batteries.
they are dual mppt in 5kva mode and their mppt model is hybrid.
do let me know what you think?
 
they are dual mppt in 5kva mode and their mppt model is hybrid.
do let me know what you think?
Only the PRIMO series can do that, based on their diagram how it shares load with utlity is basically charge the batteries with available solar power and remaining with AC power. The inverter inside works because its just converting DC to AC, so this inverter is basically a double conversion inverter, like the Flin Ultimate.

But the difference compared to a Flin Fusion is that that the Fusion doesn't need batteries to do this, it can combine both solar and AC to directly power the load without the battery, where in the PRIMO series basically charges the battery in solar and AC and the inverter just runs of the battery voltage, depending on how well the algorithm/design is the battery could be kept at 100% charge or if its a bad design it could cycle the battery by few percentage. You will have to ask the manufacturer to know about this.
The other disadvantage of the vipra primo series is that 5kva is only 4000w inverter vs flin which is 5kva=5000w. Also the vipra like other indian brands use more number of batteries you will need 8 batteries for a 5kva model vs 4 batteries for the flin.

Also not sure what are the settings you get to adjust, in the Flin you can adjust the charge and float voltage, in the primo catalog it mentions boost voltage adjust meaning there is no float voltage setting, this can be a issue for certain lead acid batteries and you cannot use lithium batteries.
 
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can you post small / brief review of your setup and benefits.
Do note I am yet to buy the solar panels, you can read below, that whole thread has lots of info on batteries and why I went with fusion
 
Is SolarEdge inverters available in India? How is the cost compared to Enphase?
Yes, they are available, check if its approved by your DISCOM.
The cost depends on if you use optimizers. The advantage of panel level control of Enphase cannot be achieved by the inverter alone in SolarEdge.
 
@adder @rdst_1

I was looking into this further to get options available for my setup. Here is some components and data I came across...
(As you guys pointed out I will stick to 5kw for now)

1) Found a few other hybrid inverters which support both high and low voltage batteries. Growatt - Low / High, Huayu - this is marketed as Cellcronic (Galaxy 6G), there are some videos on Youtube explaining its features. They allow you to use lithium or lead acid batteries, select the max grid feed and have a 5/10 year warranty. Have contacted Growatt distributor to know if they can import a specific model for a few users.

2) A company Hykon from Kerala assembles LiFePO4 batteries in India. They've launched SAFE series of batteries which cost 31K for 100Ah, about 50% higher than Exide Solatron batteries which are the best lead acid ones. Cells used internally are mentioned and have 5 year warranty. Pricing is better than Vison Mechatronics.

3)BiFacial solar module from Vikram and Waree rated at 400w for front which can go up to 480w are available for 8-9K in the market. These can be useful for folks with less rooftop space.

4) Enphase micro inverters price has come down to 7K for 'IQ 7+'. Apparently some new Chinese hoymiles micro inverters are available in India as well, with 12 year warranty, have 2 - 4 MPTTs and can be used with 2-5 panels depending on the wattage. Huayu ones are apparently available in India as well.

5) Cost of 5kVA external battery inverter, in Bangalore, is approximately 30K, 3.5kVA is approximately 15K

Other thoughts ------

Disadvantages of going off-grid ->
1) I won't be able to use the grid as a power bank. The grid allows us to bank and use power generated anytime during the same financial year. Eg: If I have high generation in March, April, May and minimal generation in December, January, grid allows us carry over that balance. If I am on a vacation where not much power is being used it goes into my account, where as its wasted in a offgrid system.

2) Can't use power generated to charge my EV. Most of us use our vehicle during the day time so the power being generated and the time at which the vehicle is standing idle is the exact opposite. Having a second power bank to charge the vehicle via stored energy is neither economical nor efficient.

Problem going hybrid right now -> (Bangalore specific)
1) No BESCOM approved hybrid inverter is readily available, only one I could find on the list was 10kW which is very expensive.

2) VFM Chinese hybrid inverters exist, but no idea if they will ever get approved in future. (Add to that the growing anti-china sentiment).

3)Shorter warranty and lower efficiency on hybrid inverters.

So, I am still confused on which way to go, exploring for now.....
Do you guys have the link for MNRE approved inverters with you by any chance ?
Great knowledge dump. Any updates on this a year later? Especially Bifacial modules, A hybrid setup, Lithium Iron Phosphate batteries etc.
 
Great knowledge dump. Any updates on this a year later? Especially Bifacial modules, A hybrid setup, Lithium Iron Phosphate batteries etc.

Well, I noticed following when I last checked,
  • 500-550w modules available now, both domestic and imports.
  • BiFacial panels are more easily available, but they require a reflective surface (white paint etc) on the roof to have any meaningful effect.
  • Cost of all solar components has gone up by 30-40% as GOI has imposed tariffs in the name of MakeInIndia.
  • Cost of components will go up another round from April 2022 as more tariffs are expected to kick in.
  • GST on solar components is up from 5% to 12% since Oct 2021.
  • Enphase IQ8 micro-inverters are available, but their use in hybrid setup depends on approval from your local ESCOM.
 
Well, I noticed following when I last checked,
  • 500-550w modules available now, both domestic and imports.
  • BiFacial panels are more easily available, but they require a reflective surface (white paint etc) on the roof to have any meaningful effect.
  • Cost of all solar components has gone up by 30-40% as GOI has imposed tariffs in the name of MakeInIndia.
  • Cost of components will go up another round from April 2022 as more tariffs are expected to kick in.
  • GST on solar components is up from 5% to 12% since Oct 2021.
  • Enphase IQ8 micro-inverters are available, but their use in hybrid setup depends on approval from your local ESCOM.
Any idea how much those 500-550w ones cost? I'd like bifacial cause I have white tiles and can paint other parts.

I saw the tariff went from 5 to 12%. This govt itself is the country's biggest enemy. Random policies with zero sense. Any idea of Indian manufacturing? Are they expected to be cheaper? The best ones, since I have limited space.

Are these single inverter per module worth it? Since they cost 8-10k? I mean that's almost 50% cost of the panel. Old ones don't seem to have got cheaper.

Any idea about Lithium iron batteries? And a setup that uses solar power first and only uses grid to suppliment or return the surplus?
 
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