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easing into solar :)


Dr. Evil

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Hi ladies and gents

 

Newbie here, so bear with me lol

 

Been doing some research on the photovoltaics thing and I think now is a good time to jump in.

I am looking at a simplified, grid tied system with, initially, a 1kW array (4 x 250w) of panels but without the battery backups.

 

The idea is to feed this theoretical max (1kW x 6hrs of sunshine) 6kWh per day back into the grid and offset some of my 30kWh daily average usage. I have an old analogue meter that can go backwards.

Much better and cheaper battery technology seems to be in the pipeline for the future, hence I would prefer to wait on this and go for a setup with a higher ROI.

 

So in essence, I am looking at a Chint SCJ 1.5kw grid tied inverter (www.sustainable.co.za). I can expand the solar array output to 1.8kW later on and it comes with a 5 year warranty.

Anyone here have any experience with these Chint inverters or the batteryless setup I am proposing?

 

Any attempts to enlighten me would be appreciated  :)

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I don't know the Chint, and I'm not an installer or someone who works with this stuff, but personally I would 1) not buy it from sustainable, and 2) go for a Fronius instead. Reason for not buying from sustainable is simply because I find them on average 10%-20% more expensive than others. Example, I just bought this unit two weeks ago for R9875. Check out the sustainable price at almost 12k):

http://www.sustainable.co.za/victron-bluesolar-mppt-150-70-12-24-36-48v-70a-charge-controller.html

 

I'd look at this Fronius:

 

http://www.fronius.com/cps/rde/xchg/SID-CDDD1E23-9579089F/fronius_usa/hs.xsl/2714_10792.htm#.VdnG_q3xCE0

 

Starts up at a low 140V too. A bit more costly though... but that's what I'd spend my money on.

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Hi plonkster

 

The data sheet on the chint SCJ 1.5kW (available on sustainable website) compares much the same to the Fronius. Startup on chint is 150V.

What is the warranty on the Fronius? It does have a wider power class so it can go up to 2,4kW of panels vs chint 1.8kW.

 

Comparable warranties would make it very tempting.

What supplier did you use for the Victron charge controller, that is a big saving over sustainable.

 

Thanks for replying :)

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I buy from a local outfit called ExSolar aka "The Importer (cc)" here in Somerset West.

 

I have to admit I know little about the Fronius. I'm a software developer and I love things with open specs or that interface well with other equipment. I like the Fronius for this reason. The same ExSolar people had someone develop a solution for them to act as a grid limiter, something you can only do if the specs are open.

 

http://www.exsolar.co.za/blog/solarenergy/solar-system-with-a-prepaid-meter-and-grid-tie-limiter/

 

Also, it interoperates well with a Victron, so if you ever decide to add backup this would be the one to have.

 

Edited to add: Quick bit of research suggest that Fronius have extended warranties, and that it varies between 5 and 20 years depending on how you structure that. So it seems it does at least match the Chint in that respect.

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Hi ladies and gents

 

Newbie here, so bear with me lol

 

Been doing some research on the photovoltaics thing and I think now is a good time to jump in.

I am looking at a simplified, grid tied system with, initially, a 1kW array (4 x 250w) of panels but without the battery backups.

 

The idea is to feed this theoretical max (1kW x 6hrs of sunshine) 6kWh per day back into the grid and offset some of my 30kWh daily average usage. I have an old analogue meter that can go backwards.

Much better and cheaper battery technology seems to be in the pipeline for the future, hence I would prefer to wait on this and go for a setup with a higher ROI.

 

So in essence, I am looking at a Chint SCJ 1.5kw grid tied inverter (www.sustainable.co.za). I can expand the solar array output to 1.8kW later on and it comes with a 5 year warranty.

Anyone here have any experience with these Chint inverters or the batteryless setup I am proposing?

 

Any attempts to enlighten me would be appreciated  :)

Residential consumers installing SSEG who wish to participate in the SSEG tariff must have a bi-directional AMI credit meter installed. The City will provide and install the requisite meters at the consumer

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Hi

If my understanding of the SSEG costs are correct, you need to be pushing back about 22kWh per day to offset the R13 daily SSEG charge at the R0.57/kWh feed in tariff they pay.

This is not a solution for the Residential user - more for businesses maybe who are producing lots more power.

 

Andrew

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Hi

If my understanding of the SSEG costs are correct, you need to be pushing back about 22kWh per day to offset the R13 daily SSEG charge at the R0.57/kWh feed in tariff they pay.

This is not a solution for the Residential user - more for businesses maybe who are producing lots more power.

 

Andrew

 

Exactly

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Hi ladies and gents

 

Newbie here, so bear with me lol

 

Been doing some research on the photovoltaics thing and I think now is a good time to jump in.

I am looking at a simplified, grid tied system with, initially, a 1kW array (4 x 250w) of panels but without the battery backups.

 

The idea is to feed this theoretical max (1kW x 6hrs of sunshine) 6kWh per day back into the grid and offset some of my 30kWh daily average usage. I have an old analogue meter that can go backwards.

Much better and cheaper battery technology seems to be in the pipeline for the future, hence I would prefer to wait on this and go for a setup with a higher ROI.

 

So in essence, I am looking at a Chint SCJ 1.5kw grid tied inverter (www.sustainable.co.za). I can expand the solar array output to 1.8kW later on and it comes with a 5 year warranty.

Anyone here have any experience with these Chint inverters or the batteryless setup I am proposing?

 

Any attempts to enlighten me would be appreciated  :)

Take off / subtract 20-30% of your calculations for inefficiencies and losses in cable, PC angle, pollution, etc. 4x 250W panels would probably deliver closer to 800W on average, and you probably won't get it for the full 6 hours.

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I have a 900W array, live just outside Cape Town. On a good sunny winters day I make 4.5kwh, on a good summers day around 5.2kwh. With 4 x 250w modules you'll be about 11% larger, so 5kwh to around 5.8kwh. I rarely see the rated power. Mostly I peak around 730w, so around 80% of rated power. Occasionally I might see more than 900w, usually on a sunny day with high white clouds which has an odd reflective effect. Max I recorded was 960w.

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Okay gentlemen, I have 2 options here on local sourced solar panels.

I'm in Port Elizabeth btw :)

 

Yingli panel vs Schutten panels. Any of you esteemed gentlemen have experience with these brands?

Both are chinese made panels but the yingli seems to be a class panel, don't know much about Schutten.

Generally, when a chinese manufacturer tries to fool you with a german name, the subterfuge is usually necessary lol

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Lol. agreed. Anyone seen the cheap powertools you can buy at Checkers Hyper now? It's branded "Schultz". Look carefully on the box, and you'll see that this is a name the Checkers people sucked from their collective thumbs. The product itself comes from the PRC (People's republic of China). It's SOOO cheap that I'm scared to even touch it. Now on their shelves I also found this Inverter-generator of the same brand... I'm too scared to even look :-)

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OK it was an awfully murky day in PE today and I only got around to testing at 4pm+.

Chopped off the test lead pins on my multimeter and soldered some replacement MC4 connectors for easy panel testing in future.

They were crappy test leads anyways :D

 

Nominal open circuit voltage on this yingli is 35.7 and nominal short circuit current is 7.19.

I was getting 34v and 0.5a at around 4:30pm on a murky day, so test conditions were not ideal.

 

http://imgur.com/0z8NBze

 

Does amperage drop off that severely on a late murky day? Hopefully 2moro will be a better day to for testing.

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Gentlemen, I have news :)

 

http://imgur.com/W9PTkY2

http://imgur.com/K9VtxsI

 

On my 255w yingli panel I have been pushing between 145w and 160w on a clear and sunny day, albeit a bit windy.

 

I found it a bit odd that a 255w panel would only produce 160w on what looks to be a good day. So I put this down to inverter / cabling losses (inverter at 90% efficiency and losses along length of DC cables.)

 

Wanted to find out exactly where the loss is though, so I hooked up multimeter straight to panel and I'm getting 36v and hovering around 4 amps.. Which correctly gives me the wattage im seeing (145w-160w). So the loss along the length of cabling to inverter and the conversion loss of inverter itself is negligible in this case.

 

I will run a few more series of tests before I get more panels and I mount on garage roof. I would have liked to have different sourced 250w panels on loan to test, So I can run benches in same conditions and work out price / performance and best bang for buck panels, but alas.

But in my mind I should be getting more amps in todays light conditions and cool weather between 20-25 degrees.

 

Anyways, I will take 160w of free power all day, every day :)

 

PS Chris you should have popped in for a beer. Plonkie how much you generating in CT for the day.

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