[Emvi]

Cleaned the solar panels at my home after quite a while. To be honest, I don't remember when I cleaned them last. The amount of dirt accumulated on the panels was simply unbelievable. The dirt was quite stubborn as well. I missed clicking pics prior to the cleaning. It would have made a good 'before & after' comparo.

First I wipe cleaned the panels with water using a piece of cotton cloth. Later I used soap water to clean the panels with the help of a scrub pad. Carefully rinsed the panels after that and finally wiped them dry using a microfiber cloth.





After cleaning:

[Shreyans_Jain]

Originally Posted by Emvi

Cleaned the solar panels at my home after quite a while. To be honest, I don't remember when I cleaned them last. The amount of dirt accumulated on the panels was simply unbelievable. The dirt was quite stubborn as well. I missed clicking pics prior to the cleaning. It would have made a good 'before & after' comparo.

Weekly cleaning is a must to maintain consistent output. Dirty panels produce as much as 30-40% less power. We make sure than our panels are hosed down every Sunday.

There are automated solutions available for cleaning the panels. A pipe circuit with holes (shower like setup) is installed above the panels and is connected to a pump and timer system. The system washes the panels on its own every day. All big name solar providers have this option as an add-on.

[Shreyans_Jain]

With the smoggy winter season behind us, the plant’s output has been a revelation. It is finally performing the way it should. 950 units have already been generated in 21 days this month, and it looks set to cross 1200 units over 31 days. Daily average has been over 40 units a day with weekly cleaning. Production has shot up to over 50 units every time the panels were washed, and then gradually drops as dust and dirt settle on top. I may add an automatic washing system in future for daily cleaning.

It’s a 10kw plant.

Sharing some screenshots.


Daily output graph. Longer and sunnier days = better output. Should improve as summer progresses and days get longer.


Output over a week. Notice how production increases after the panels are washed and then gradually reduces. Regular washing is a must for getting proper output.


Month on month. Dirty and smoggy winter totally screwed the production and the the ROI calculations. Plant is set to exceed 1000 units a month for the first time since it was commissioned in September 2021.

Anyone living in northern India who is planning to invest in a solar plant must take this loss of production during winters into account.

Our electricity distribution in Haryana works glacially slow. I am yet to receive a bill ever since my net metering got activated. Will be able to share actual cost benefits and ROI data only after we get a bill from the department.

[Swarup5]

Rooftop solar - Grid-connected system.

Few stats :
- Installed capacity: 5kw
- Years since installation:6y
- Power purchase agreement (25y) - 9.72/unit
- Number of units generated till date: 36800
- Average production per day: 16
- Inverter used: Power one
- Solar panels: Nanosolar India GIGS panels
- Total cost @2015

Summary: Has been the best investment for using the empty roof space. Bi-Weekly cleaning is required due to dust accumulation(automated sprinkler is not sufficient ). Without cleaning generation drops by a good 20-30% overall. Settlements of revenue by CHESCOM has been rather erratic and error-prone. Now nearing break-even of invested money and start of free green power for future.
Have faced 2 downtimes with Inverter with repairs costing around 5k each time.

[vj_v3]

Originally Posted by Swarup5

Rooftop solar - Grid-connected system.

Few stats :
- Installed capacity: 5kw
- Years since installation:6y
- Power purchase agreement (25y) - 9.72/unit
- Number of units generated till date: 36800
- Average production per day: 16
- Inverter used: Power one
- Solar panels: Nanosolar India GIGS panels
- Total cost @2015

Summary: Has been the best investment for using the empty roof space. Bi-Weekly cleaning is required due to dust accumulation(automated sprinkler is not sufficient ). Without cleaning generation drops by a good 20-30% overall. Settlements of revenue by CHESCOM has been rather erratic and error-prone. Now nearing break-even of invested money and start of free green power for future.
Have faced 2 downtimes with Inverter with repairs costing around 5k each time.

Attachment 2287126

Power purchase at 9.72/Unit? really? Does it change?
What was the plant cost in 2015?



Offtopic - My first settlement for 174 units export settlement was added to my TSSPDCL billing account at ~ Rs 4.30 this month.

need to figure out way to get the settlement to bank account before next settlement in June.

[Swarup5]

Originally Posted by vj_v3

Power purchase at 9.72/Unit? really? Does it change?
What was the plant cost in 2015?



Offtopic - My first settlement for 174 units export settlement was added to my TSSPDCL billing account at ~ Rs 4.30 this month.

need to figure out way to get the settlement to bank account before next settlement in June.

It is 9.65/unit and not 9.72/unit net metering method .( I did a cross check on the Power purchase agreement now). It is for 25 years that the rates will hold good . Karnataka had very generous power purchase agreements to encourage more rooftop installations, but now I’ve heard lower rates being the norm .

Cost of installation:4.5L including the fabrication works .

Settlement of bills and billing itself is quite a pain . Things are improving and settlement times are improving but at snails pace . As of now the amount gets credited to bank account directly.

[ObsessedByFIAT]

I am planning to install a rooftop solar panel system and have run in to a lot confusion and questions. Looking for some advice from all the experienced folks here! These might be real noob questions, but my research is not yielding the information I am trying to figure out.

Some details of where I plan to install:

- The installation will be done on roof top, measuring appropriately 500/600 sq.ft. in PCMC region of Pune.
- The house is east facing and gets bright sunlight right from morning to sunset.

Questions that I have :

1. What should be an approximate cost I am looking at if I would like to run 2 AC, 2/3 Coolers, 2 Geysers and rest of the standard home equipment? Consider around 350 to 450 units a month.
2. What are the pros and cons of having a on-grid vs off-grid ?
3. What are the major recurring costs I am looking at? Battery replacement costs?
4. If I would like to go on-grid, what types of permissions would I require from local authorities?
5. How does the billing work? Is it like the bill itself is reduced or I first have to pay upfront and can expect a credit in my bank account?
6. Is it a better economical decision to just charge an inverter through solar have have only limited coverage like a few bulbs and fans running off of the inverter?(I know, this question can be a bit tricky to answer as it would depend on my requirements. I would love to know your thoughts)
7. Is there a drastic difference in electricity production during rainy / winter season as compared to summers?
8. Sometime down the line, I may plan on constructing a store room / additional room on roof. Are there some basic things that I should keep in mind while the installation of solar panel?

I plan to close the installation work before end of May this year if everything works as expected!

Thank you in advance for your words of wisdom!!

[skumare]

Originally Posted by ObsessedByFIAT

I am planning to install a rooftop solar panel system and have run in to a lot confusion and questions.

Questions that I have :

1. Consider around 350 to 450 units a month.
[i]5KW unit will produce ~16 units/day on average across the year. This is a conservative estimate.[/]
2. What are the pros and cons of having a on-grid vs off-grid ?
While you save on the inverter cost and its maintenance in an off-grid system, the associated battery cost and their maintenanace will be very high and may not be worth in the current scenario. Once the storage technolgy improves, off-grid may become viable.
Unless you have frequent power-cuts or blackouts, an on-grid system with adequate UPS/Inverter is advised.
3. What are the major recurring costs I am looking at? Battery replacement costs?
If you go for off-grid - yes.
4. If I would like to go on-grid, what types of permissions would I require from local authorities?
Typically your vendor takes care of these incl subsidy, chai-pani etc. At the minimum, you need roof-top system approval, subsidy processing and then the process to replace your current meter with a net meter.
5. How does the billing work? Is it like the bill itself is reduced or I first have to pay upfront and can expect a credit in my bank account?
Your consumption is deducted from current month export and previous carried forward credit. In Hyd, we get the minimum bill (Rs 180) every month if you are in the credit side.
6. Is it a better economical decision to just charge an inverter through solar have have only limited coverage like a few bulbs and fans running off of the inverter?(I know, this question can be a bit tricky to answer as it would depend on my requirements. I would love to know your thoughts)
Yes, this is the model suggested unless you have specific issues with grid power supply.
7. Is there a drastic difference in electricity production during rainy / winter season as compared to summers?
In my 3KW system, (Dec/2021 till date), the lowest produced is 8units on rainy/cloudy days. Dust in the air around your house will also impact the production.
8. Sometime down the line, I may plan on constructing a store room / additional room on roof. Are there some basic things that I should keep in mind while the installation of solar panel?
You will need to go for elevated structure in this case. However, note that if you go for more than 6ft tall structure, cleaning will be a pain. You will need to have a tall platform around the structure to walk around for cleaning.

My thoughts given inline.

[ranjitnair77]

Originally Posted by ObsessedByFIAT

I am planning to install a rooftop solar panel system and have run in to a lot confusion and questions. Looking for some advice from all the experienced folks here! These might be real noob questions, but my research is not yielding the information I am trying to figure out.

I'm in the process of installing a 5kw system in my home in Pune. skumare has already answered several questions. Here is some additional points and feedback

• I’ve closed the contract with a vendor for 3.65 lakhs for a 6kw on-grid system. The vendor will do everything end-to-end. Please use a vendor as MSEDCL is notoriously bureaucratic and spending your time in process will only result in frustration.
• You have zero need for off-grid as the power situation is okay in Pune and PCMC. Please only install a simple on-grid system with net-metering.
• Keep your home inverter running as as usual. Do not try anything complicated with the solar system. Just focus on generating power and feeding it to the grid.
• Bills are pretty simple. There will be a basic utility bill (a few hundred rupees, not sure exactly how much). So if you generate 300 units and consume 350, you are charged for 50.
• If you generate 350 units and consume 300, the balance of 50 units will be rolled over to the next month.
• MSEDCL will make the balance zero at the end of March of every year if you have generated extra units. They will not pay you anything so you start afresh on April 1.
• Ideally the panels should face the south. However it’s okay for the panels to face east or west if a south alignment is difficult. You can always add additional panels to make up.
• Generation will be lower in rainy/winter season but consumption is also lower so it should square off. There are many factors at play (weather, alignment, dust). You will only know for sure once you have installed and observed for a full season. Do ensure that the panels are clean as that is fully in your control.
• Commissioning is not possible in a month. You need to first get the sanction from MSEDCL. Then you will install the system. Then there are further inspections. Then metering is enabled. You should realistically expect the process to take 3 months. Most of it will be required by your vendor for pushing the process at MSEDCL. The actual installation will only take a few days
  

[ObsessedByFIAT]

Originally Posted by skumare

My thoughts given inline.

Originally Posted by ranjitnair77

I'm in the process of installing a 5kw system in my home in Pune. skumare has already answered several questions. Here is some additional points and feedback

Thank you skumare and ranjitnair for sharing the details! These are some really great inputs!

Will look for some reliable vendors around PCMC area.

[skumare]

Originally Posted by ObsessedByFIAT

Thank you skumare and ranjitnair for sharing the details! These are some really great inputs!

Typically, 5KW system means (15 or 16) * 330w panels, which take up 32sqmt area. You can go for a hybrid structure model, where some of them are placed on the terrace now and later shifted to the top of the room once built and the rest on an elevated structure or on the rest of the terrace. It all depends on the space/shape you have on the terrace and your plan.

[ritesh_44]

Originally Posted by ObsessedByFIAT

I am planning to install a rooftop solar panel system and have run in to a lot confusion and questions. Looking for some advice from all the experienced folks here! These might be real noob questions, but my research is not yielding the information I am trying to figure out.

Some details of where I plan to install:

- The installation will be done on roof top, measuring appropriately 500/600 sq.ft. in PCMC region of Pune.
- The house is east facing and gets bright sunlight right from morning to sunset.

Questions that I have :

1. What should be an approximate cost I am looking at if I would like to run 2 AC, 2/3 Coolers, 2 Geysers and rest of the standard home equipment? Consider around 350 to 450 units a month.
2. What are the pros and cons of having a on-grid vs off-grid ?

If you are in city and there is not much power cut along with existing power backup, go for on grid with net metering (if Maharastra allows). On grid inverters don't work in case of power cut (to prevent shock on anyone repairing the power line, since the excess power generated is exported to the grid). Nowadays there are new inverters coming with ZED devices which can work even with power cut but these might not be allowed by power discoms (better confirm with the vendor) Off-grid is costlier and might not be beneficial for city use. If you are having existing backup inverter and very less power cut, on grid is sufficient.

For on grid solar inverters, most popular ones are string inverter and microinverter. In string inverter all the panels are connected in serial to a single central inverter. Its cheaper but if any single panel has shade/performance issue, all other panel's performance drop's down. If your installation area is without any shade and you can easily clean the dust regularly, string inverters will work fine.

Microinverters are costlier since each panel has its own inverter and hence the performace is not dependant on each other. But these are slightly costlier.

3. What are the major recurring costs I am looking at? Battery replacement costs?

For on grid inverter there is no major recurring cost apart from regular dusting/cleaning. Most of the panels have 20/25 years performance warranty while the inverter will be having 5 years warranty(some brands give extended warranty). Since these have mostly non-moving parts the chances of failure are similar to any other electronics equipment.

4. If I would like to go on-grid, what types of permissions would I require from local authorities?

In my case vendor took care of all the formalities apart from one visit to main power station. It took nearly 45 days from the day of installation for approval, which was higher than normal according to my vendor since the executive engineer was signing something like this first time in my area, he was hessitant/(wanted something extra?) but in the end I didn't had to pay anything extra from my side apart from 500 given to guy who came to install solar net meter.

[quote]
5. How does the billing work? Is it like the bill itself is reduced or I first have to pay upfront and can expect a credit in my bank account?[/[quote]
For net metering, the bill itself is reduced (its "net units imported" - net units exported). In day-time, the power generated is first used by house and only extra power is exported. If the power generated is not sufficient, the difference is imported from grid.)

6. Is it a better economical decision to just charge an inverter through solar have have only limited coverage like a few bulbs and fans running off of the inverter?(I know, this question can be a bit tricky to answer as it would depend on my requirements. I would love to know your thoughts)

It depends on your usage and duration of power cut, if its not much, a new inverter costs around 5000 and a single lead-acid battery around 15000. Its much cheaper and efficient than having off-grid solar since if power cuts are not much, you will be wasting money on additional batteries which will be mostly not utilised. (My vendor had quoted for 2 batteries costing 30000 along with higher priced hybrid inverter. Overall for 3kw system it was 60000 more. Also, vendor informed hybird inverters don't perform as good and on-grid words, not sure how much of this is true)

7. Is there a drastic difference in electricity production during rainy / winter season as compared to summers? [

There is difference when sun is not there (rain, clouds etc) here is a graph of my panel on a normal day vs cloudy dayAttachment 2303044

Attachment 2303045
Regarding performance in summer vs winter- performance depends on two things, amount and duration of direct sunlight and the ambient temperature. Till now I have got highest performance in October and January on sunny day. In winter at my place, there is lot of fog, hence the performace was low due to lack of sunlight. Since April, due to heat, even though there is sunlight full day and the duration of sun is higher, overall generation is not so high. Here are my charts for monthly and daily performace for 3kw system. (Note, with daily/weekly cleaning you can increase the performance by ~20-25%, the vendor had installed my panels at height and its not easy for my parents to clean regularly. I clean it on ladder whenever I'm at home. Also just hosing with water doesn't works well since the dust is sticky, you need to mop it with microfiber cloth. It would be better if you install at lower height where its easier to clean with cloth )

8. Sometime down the line, I may plan on constructing a store room / additional room on roof. Are there some basic things that I should keep in mind while the installation of solar panel?

Make sure it doesn't shades the panel. Also you can use the panels as shade your if vendor is willing to put at height, but make sure to have some way to clean the panel

I plan to close the installation work before end of May this year if everything works as expected!

Thank you in advance for your words of wisdom!!

[ObsessedByFIAT]

Originally Posted by ritesh_44

---snip----

Thank you Ritesh for this detailed information! Highly appreciated!
This actually the kind of inputs I was looking forward to. Trust bhpians to never disappoint!

[aim120]

Those who have solar in bangalore, I hear that one can only put a installed capacity equal to that of the sanction load.

Now to increase the sanction load, apart from the additional deposit. One also has to pay extra Rs95(112 inc gst) per month for every 1kwh increase in sanction load.
So for 5kwh one has to pay Rs 558 every single month as fixed charges. So do this charges stay on the bill when you get net metering.

[ritesh_44]

Originally Posted by aim120

Those who have solar in bangalore, I hear that one can only put a installed capacity equal to that of the sanction load.

Now to increase the sanction load, apart from the additional deposit. One also has to pay extra Rs95(112 inc gst) per month for every 1kwh increase in sanction load.
So for 5kwh one has to pay Rs 558 every single month as fixed charges. So do this charges stay on the bill when you get net metering.

In Uttar Pradesh, fixed charges remain. It should be same in Karnataka, since the extra units are rolled over for next month