so in short,

you spend and build solar farm at ur home/shop/commercial building that's belong to you,

all of the power generated from your solar farm will be sending and feeding to TNB, then TNB pays you by amount of energy u generated,

your place still using power from TNB, and pay like usual

so you buy something very expensive then you get random income depend on weather and condition of the equipments?


pretty good, but really need maintain well

This post has been edited by squall0833: Nov 18 2013, 02:44 AM

We need to understand the actual condition of the site to decide the inverter/s needed and the strings configuration.
Let me know and we could make arrangement for the site survey.
I am quite familiar with PowerOne Aurora inverter (both 1phase and 3phase).

Locke

Your summary is precise.
You got it
But one thing to note : The income forecast is not random, income calculated based on the yearly Malaysia weather statistic ( which does not change that much )
And you ONLY invest in an expensive system, knowing that you have a 21 year contract in hand , with TNB which i dont believe will go bankrupt.

Meaning your risk is actually "controlled" , for your investment , to gain a stable, solid income and return.



PM me if interested to find out more.
We do free site survey. We are SI

QUOTE(abcstop @ Nov 15 2013, 02:15 PM)

If using 2 inverter, how many string is the best configuration? 3 string? For two 6k inverter, two string for the 7.5k and one for the 4.5k?

QUOTE (andrewsh,Nov 15 2013, 05:10 PM)

Instead of talking about the number of strings or which configuration of strings is better. I believe we should consider the number of independent MPPTs you have from your inverter. Normally for medium size(I guess >3kW) inverter will have 2 MPPTs with either 1 or 2 strings per MPPT. What is the best configuration will very much depending on whether you have shading issue. Ideally if you do not have shading problem, the next consideration is to maximize the string voltage to match the highest operating efficiency of your inverter. If you have shading issue, I would like to have different MPPTs to handle different shading.

You should consult your service provider to get the max output possible depending on your roof and surrounding condition.

QUOTE(locke,Nov 18 2013, 03:42 PM)

We need to understand the actual condition of the site to decide the inverter/s needed and the strings configuration.
Let me know and we could make arrangement for the site survey.
I am quite familiar with PowerOne Aurora inverter (both 1phase and 3phase).


Helo abcstop,

Agreed with AndrewSH and Locke,

it is not that straight forward.
Another consideration is which facing, that particular roof portion can fit the minimum number of solar panels or not.
Because there are minimum number of solar panels per string. And the number change depending on the solar panel brand and model, and inverter brand and model.
And many more parameters to consider.

Responsible SI ( like us marketing a bit ) will do proper site survey, and take many parameters into consideration, and give you an optimum solution to maximize your investment.

PM me if you interested.

Anyone clean the Solar panel and a notice the performance changes in the inverter ?

There is no evidence of 2 inverters are more efficient than 1 inverter and power disparity would cause lost of efficiency.

This post has been edited by locke: Nov 19 2013, 01:20 PM

You are right that power disparity is not the right parameter to determine lost of efficiency, I made a mistake there. What I was referring to was the string voltage.

The reason I choose to have 2 inverters is to cater of a big delta in string voltages between group of panels and also with the flexibility of more MPPTs to play around in case if there are shading issue. For example, due to roof design limitation, I have 1 string output only 300V and another string is generating 600V. By splitting these strings to separate inverters that optimized for these working voltages individually maybe a good option(in my opinion). If we feed these 2 strings(300V & 600V) into single inverter, then one of the strings may not be operating at max efficiency(~ 1% to 2% drop).

As I am not the system integrator, I may not have the practical side of the experience you have. All my argument is based on data sheet specification, so I may missed out something. But I still find this to be interesting topic to discuss and bounce ideas around for our education purposes.

Comments?

Educated user tends to make mistake in string voltage.
When you have too many strings, the string voltage will be low. When low string voltage, your inverter wont startup until reach noon and shutdown early.

Slightly lower efficiency. 2 smaller inverters have less efficiency than 1 bigger inverter.

More equipment. With extra strings and inverters, your breakers, fuses and SPD are more. The chance for equipment is higher.

It is true that low string voltage can be a problem if match with high turn on voltage inverter and this mistake can happen if not careful.

Ideally we would like to have as few string as possible to max the turn on time. The need of more strings happen due to either the limitation of inverter or panels facing different direction or shading. Never the less, still need to take care of the turn on voltage if not, like what you said, the system won't turn on until noon.

Are you using single inverter or multiple inverter for your system?

My 12k system is on:
- single inverter
- 3 strings (2 to input A, 1 to input B)
- each string connects to a 4 kWp output (16 panels)

Logical I believe lesser electronics or cable length is more efficient in electrical and electronic terms. Each components adds resistance and induce some losses... So the more you have of it, the less efficient it would be.

You system configuration looks very evenly distribute with both MPPTs having similar voltage. I guess the performance should be good.

12k, so cheap!?

He meant 12kw

My 8kw system is on double inverter, 2strings(16 panels each). It's been 63 days n tnb meter registered 1771 exported. Both inverter readings(combined) 1806 which is almost 2% loss

Do the performance from both inverters similar to each other?

Nope. One is higher than the other. I think this is caused by my roofs split design ie one part is slightly higher. Each part has 16 panels...u r up late bro. I just finished weekly badminton game

hi, what are your daily or monthly output from 12kw panels the last month or so in our current KL (or west MY) gloomy weather?

Anyone heard or bought package from Senheng?

this seda FIT applicable in sarawak yet?

I think only sem msia so far...but I might be misinformed