[Holyghost]

Originally Posted by Thad E Ginathom

Thank you lurker. They have changed their name to Swelect, but still have the same large head office in Mylapore.

I understand that their range covers everything from small domestic to large industrial, including the biggest solar-power farms in the country. It might well be worth talking to them before going ahead, although there is always the danger that it would not be very hard to talk me into spending lakhs that I cannot afford to spend!

I still have this dream: make the sun pay for itself by having enough solar power to run at least one AC machine .

If you want to run AC on solar, grid tie setup is the only cost effective way. My advice is not to mix up an inverter and a solar setup. An inverter is a power backup system and has its limitation as to its scalability. Solar setup is a scalable and modular system that you can keep adding as your requirement increases or when your budget allows for an upgrade.

But for starters, A hybrid inverter with 2 or 4 panels is not a bad idea. You can later add few more panels and a Grid tie inverter and use the inverter purely for backup purpose.

You should also check out the micro grid tie inverters. I do not have the pricing details, but they do look promising. Micro grid ties are 250-300W miniature inverters which are connected to individual panel.

I have a 3kw grid tie system and runs 2 AC in my home. For the month of Oct which was mostly cloudy with occasional rains, the system produced 380 units of electricity and has offset the consumption of ACs.

[Thad E Ginathom]

Originally Posted by Holyghost

If you want to run AC on solar, grid tie setup is the only cost effective way. My advice is not to mix up an inverter and a solar setup. An inverter is a power backup system and has its limitation as to its scalability. Solar setup is a scalable and modular system that you can keep adding as your requirement increases or when your budget allows for an upgrade.

Yes, thank you for emphasising that point. I see that one can get a 5.5kva inverter from Su-Kam, and probably from others too, but how long is the backup going to last once AC machines are in the picture? The picture needs to include a room full of batteries.

I guess that sort of stuff is for supporting vital services, not for the middle-class home.

In fact, a 3kva Honda portable petrol generator can be had for less than one lakh. If my aim is to be able to run just one AC through all-day powercuts, that would be a better solution (and hey, it's on my wish list!)

But for starters, A hybrid inverter with 2 or 4 panels is not a bad idea. You can later add few more panels and a Grid tie inverter and use the inverter purely for backup purpose.

Yes, it makes sense.

You should also check out the micro grid tie inverters. I do not have the pricing details, but they do look promising. Micro grid ties are 250-300W miniature inverters which are connected to individual panel.

I read about this yesterday: by converting each panel to AC, it prevents problems with one panel from bringing the others down.

I have a 3kw grid tie system and runs 2 AC in my home. For the month of Oct which was mostly cloudy with occasional rains, the system produced 380 units of electricity and has offset the consumption of ACs.

It would not offset the consumption of ACs in Chennai... but every little counts

[Thad E Ginathom]

Later that Day...

OK, so here is my idea for starting small...

The Sukam 1100va (despite its name, seems to be an 850kva capacity inverter) is a 12v model, so a straight swap in for existing inverter. I can buy this with 300w of solar panel for around 25K in approx round numbers. It can be upgraded to 500W of panels and 300amp-hour of battery by adding second battery in parallel; still 12v, but more back up.

Sukam reviews on Amazon are poor. Amazon reviews are... well, not the most reliable in the world. Any comments (one happy Sukam user noted, a few posts ago).

[hserus]

I can recommend Microtek - a friend with a battery dealership (in Adyar) sold me one - of course, with an Exide battery rather than solar - that's been a workhorse for quite some time. If you want I can put him in touch with you, Thad? PM me.

[Thad E Ginathom]

As mentioned, we had APC before, and I'd go that way again except I'm determined to get something solar-ready if not some actual solar power. I am sitting in front of a computer+monitor+etc that comes to 160W, for most of the day or more. That is a couple of units a day, I think.

I guess that the top three names are Luminous, Microtek and SuKam. I could take a vote among you guys! Oh, and Numeric, as mentioned above.

We could probably buy anything through our local electrician, but he is great at wiring and installation, but not at inverters. I need someone who understands solar, too. If your guy can help, then do please send me his details!

[hserus]

APC is expensive and not terribly reliable i fear, compared to these. The inverter you buy also needs to have as close to a sine wave output as possible.

This is fairly reliable I believe - http://www.microtekdirect.com/1130solars/

I will call him later today if I can still find his number and then PM you.

[Thad E Ginathom]

Originally Posted by hserus

APC is expensive and not terribly reliable i fear, compared to these. The inverter you buy also needs to have as close to a sine wave output as possible.

Our APC inverter never gave any problem until it got filled with water!

This is fairly reliable I believe - http://www.microtekdirect.com/1130solars/

It does not seem to have shared charging, although this product does.

It is really very tough to understand the published details of these machines from the various manufacturers. So far, SuKam does the best job of convincing me that their box does the most. But that could be just presentation.

I will call him later today if I can still find his number and then PM you.

Thanks!

[Thad E Ginathom]

I just had a meeting with a technical guy from a company in Adyar, JSS Power Systems, who are distributors for Su-Kam [and Luminous?] and also sell Luminous and Microtek.

He is more techie than sales and only has approximate prices in his head, but I have a short-list of two systems: the Su-Kam Brainy 1100 (relatively cheap to implement, almost just an inverter swap-in plus small panels; 12v, would use existing battery) and a Su-Kam PCU 1Kva system, which is much more expensive but I might be able to stretch to it. Will get quotes tomorrow. This is a 24v system, so I have to invest in a second battery as well as a lot more solar panel area.

Hey ho, who knows how much I'll actually get from the sun --- but this is one of my dream gadgets!

(My solar water heater is a dream gadget; there is no chance at all that it will ever pay for itself with just the two of us in the house, but I love it anyway.)

[hserus]

Oh well, I am sorry - I wanted to put you in touch with my guy but it slipped my mind. As it happens I think you contacted much the same person. Highly techie, yes.

Go with his reco .. you'll like it.

[Thad E Ginathom]

That's ok... it happens.

Mr Sivakumar? Seemed very straightforward. By coincidence, it seems he lived just behind our house, up to a couple of years ago. Lucky he wasn't here last December!

This is the product I want to be able to afford: Solar PCU

[hserus]

The spec looks good and it is a good brand. I think you'll be quite happy with this choice.

Yes he's very straightforward and knows his stuff.

[JMaruru]

Originally Posted by Thad E Ginathom

That's ok... it happens.

Mr Sivakumar? Seemed very straightforward. By coincidence, it seems he lived just behind our house, up to a couple of years ago. Lucky he wasn't here last December!

This is the product I want to be able to afford: Solar PCU

Can we use our existing solar panels used for water heating, to power this Solar PCU?

Could you please provide me the contacts of this knowledgeable person?

[Thad E Ginathom]

Originally Posted by JMaruru

Can we use our existing solar panels used for water heating, to power this Solar PCU?

No. Not unless you can get the water hot enough to generate steam to power a turbine! I gave the same answer to my wife yesterday. It is not at all compatible. I'm sure somebody, somewhere does this! But consider: high-pressure steam vessel; turbine; generator. Could maybe cost as much as my house!

Could you please provide me the contacts of this knowledgeable person?

This is the company: jss Power Systems but it is local for Chennai.

Here's one thing I just noticed which we never thought/talked about. PWM/MPPT? I see both are available. I don't know which he is going to quote for. I'll have to see.

[Thad E Ginathom]

The quote is on the high side. Just over 1 lakh for 1KVA of panels with Solar PCU.

Unsure that I can do that. Will negotiate with Mrs G next week. She's away being a grandmother right now.

Even the quote for the "Brainy" system is a little high.

[Holyghost]

Originally Posted by Thad E Ginathom

The quote is on the high side. Just over 1 lakh for 1KVA of panels with Solar PCU.

Unsure that I can do that. Will negotiate with Mrs G next week. She's away being a grandmother right now.

Even the quote for the "Brainy" system is a little high.

My 3kw SuKam grid tie setup costed a little over 2Lakhs. 1L+ for a 1kva battery based system seems too high. Please check the cost of having a 1kw grid tie + a normal inverter.

MPPT chargers are considered better than a PWM based charger and claims upto 25% more efficiency during low sun light. MPPT chargers costs significantly more than PWM and I am not sure if it is worth the additional cost.

The budget battery based systems are PWM and the Grid Tie inverters are mostly MPPT. In MPPT setup, the panels are connected in series and the input voltages for a 1kva system will be around 100V. In PWM, the panels will be mostly connected in parallel to match your battery voltage. So a 12v PWM system will have all panels connected in parallel while 24v system will have pairs of panels connected in series which will be connected in parallel with other pairs of panels.