Energy Matters Forums

[superman1]

I read that now, Tracker. Thanks.

I finally have had a clear day, about mid 20's
Yes I've lost 20% of my powers. ..
But at noon now, I am getting max of about 5kW out of 5.4kW.
80% is 4.32.
90% is 4.96
95% is 5.13

So I hope at least I got a little more for what I paid for with Sunpower.
In a way, it's best they don't go to peak, otherwise with clouds = Bl☻Wn ¶ñvΘr╦ëΓ.

There should be an additonal rating system. Peak is honest, but misleading.
They should also have the real world rating (RWR).

It's like watts ratings in speakers or amps; they have used the peak power which is not the real world rating (RMS).

[Inspector]

There should be an additonal rating system. Peak is honest, but misleading.
They should also have the real world rating (RWR).

It's like watts ratings in speakers or amps; they have used the peak power which is not the real world rating (RMS).

I agree, but being involved in that industry in the past, I am surprised it's taken so long for someone to make the comparison

I often wondered how long it would be before inverter manufacturers would catch on to pointless limitations imposed government in the area of system size, where some states have a 5kw inverter limit. They would simply de-rate their inverters but advertise them as being "more efficient" than their competitors, similar to what happened in the car audio industry many years ago when competition classes were based on power output of amplifiers. So instead of a typical 300W(peak) rating (2x150W) they would "advertise" them as being only 100W (2x50WRMS) but in actual fact would put out well over a much cheaper amplifier "rated" at 300W (or more). I guess it would be quite difficult to sell such a de-limited inverter in the real world (there's no competition for output apart from adding more panels to get a larger system). It's an interesting comparison, though.

[Gordon-Loomberah]

...There should be an additonal rating system. Peak is honest, but misleading.
They should also have the real world rating (RWR).

There is, have a look at the back of some good brands and you see NOCT info, temp might be 47C, and output is measured at an ambient 20C and 800W/m^2...

For example see here http://am.suntech-power.com/images/stories/pdf/datasheets/july2011/stp285_24vd_ul_superpoly285-290%20h4%20connector.pdf

[Tracker]

Yes I've lost 20% of my powers. ..
But at noon now, I am getting max of about 5kW out of 5.4kW.

I think that it has MORE to do with the Solar Industry being far more honest and direct with customers.
Selling a 2Kw system, should be simple.. It generates 2Kw on an ordinary day.. and that means when it's a normal temperature that you would encounter with 1000W/M2..

Almost every person I have spoken to, having bought a system, has said "...but something must be wrong.."

If so many customers are confused, then there IS something wrong

My house system is supposed to be 12panel 2Kw, but I only run 11 to prevent blowing the GCI.
That's 1870W Design.

During this week I have seen some sustained outputs of about 1700W, where the nominal max would be 80% or 1500W. I have also seen some peaks of over 2000 with Cloud-Edge-Effects.. It's nothing to get excited about, but it's interesting.

My gripe WAS and IS that customers are NOT really getting what they paid for, but as everyone is treated the same, I guess that there is nothing anyone can do.
Why does MY system generate 1.6Kw and one either side, under the same conditions, produce 1.4Kw and 1.1Kw.. Who draws the line in the sand, saying what is value for money ?
Meanwhile our Government sends out inspectors to ensure that the RED on the door label, is the right RED, and that the Installer did not drill A/C sheeting, etc. etc. but do nothing to determine if the system is working to spec/value..

It's like buying 1Kg of meat that only has 800g of meat and 200g of water.. I wonder if Fair Trading would openly accept that you must eat it quickly after thawing, so the pumped water does not run out..
..
.

[Smurf1976]

It's like buying 1Kg of meat that only has 800g of meat and 200g of water.. I wonder if Fair Trading would openly accept that you must eat it quickly after thawing, so the pumped water does not run out.

Reminds me of a certain firewood merchant who used to run a sprinkler on one of their wood piles all night. No prizes for guessing which pile the next day's deliveries were taken from but pity the poor customer left with a lot of steam going up the chimney.

It's legit to leave wood in the open and it does actually dry that way and believe it or not, the rain does contribute to this drying (true). But deliberately adding water immediately prior to delivery is another matter...

[Smurf1976]

A completely clear day today so here's the production data for my two systems. Both are located on my house in Tasmania.

System 1 = 8.95 kWh produced today (the highest I have ever seen is 8.99 kWh)
Panels = 1.36kW effective output comprised of 6 x 170W + 2 x 190W in one string
Pitch = 22 degrees
Orientation = 20 degrees West of true North.
Inverter = SMA Sunny Boy 1100

System 2 = 8.64 kWh produced today
Panels = 1.52kW comprised of 8 x 190W in one string
Pitch = 30 degrees
Orientation = 70 degrees East of true North
Inverter = SMA Sunny Boy 1100

There is absolutely no shade on any of the solar panels.

In terms of historical output, System 1 produced 1635 kWh during 2011. System 2 wasn't operational for the full year so I don't have data for that.

Consumption today I would estimate at 6 kWh on the normal electricity tariff, 3 kWh off-peak (heat pump HWS) and 1 kWh for gas. The consumption figures are estimated not measured but they should be fairly close I would expect. Obviously consumption isn't that low every day, but it would have been today.

[Inspector]

Why does MY system generate 1.6Kw and one either side, under the same conditions, produce 1.4Kw and 1.1Kw.. Who draws the line in the sand, saying what is value for money ?

That is why it's so important that anyone considering (any goods or services) fully research the company before signing on the dotted line, and getting recommendations from friends/relatives or those with experience would also help. I really feel sorry for those people that fall victim to predators in (any) industry.

Meanwhile our Government sends out inspectors to ensure that the RED on the door label, is the right RED, and that the Installer did not drill A/C sheeting, etc. etc. but do nothing to determine if the system is working to spec/value..

The government is only worried about firstly saving face, secondly safety, and definitely not about how well systems are performing. If anything, they would be happy they are under-performing; we all know they wanted to scrap the feed-in tariff, and I wouldn't be surprised if the threat of a drop in feed-in tariff returns come next election if not sooner.

[Tracker]

But at noon now, I am getting max of about 5kW out of 5.4kW.

I had meant to ask for clarification.. You recognise the relative power deficiencies in %, and then say that you are getting more than 90%..
Is that for sustained periods.. ie constant power, flat-top power, or those teasing peaks, that you wish could be there for good..
..
.

[Smurf1976]

Another cloudless day today and marginally higher production. Interestingly, this was despite it being significantly warmer with a maximum of a bit over 30 today versus just under 21 yesterday.

System 1= 8.97 kWh today (8.95 yesterday)

System 2 = 8.66 kWh today (8.64 yesterday)