Renewables: "talking 'bout my generation"

John_Pierpoint

Never mind cat heating - dog heating has an antique heritage


Explanation:
les affuteurs travaillaient allonges avec un chien sur le dos pour leur transmettre un peu de chaleur car les meules etaient actionnees par l’eau très froide de la rivière. Avec l’image je comprends mieux.

3.6 kWp inverter North side of Thames estuary facing SE on 30 degree roof

kWh Oscarz
20.56 05.72 04/03 Monday
15.71 04.36 05/03 Tuesday
06.12 01.70 06/03 Wednesday
03.78 01.04 07/03 Thursday
01.10 00.31 08/03 Friday
02.11 01.27 09/03 Saturday
01.67 00.46 10/03 Sunday

I had to double check Monday as it is the best result since [STRIKE]October.[/STRIKE]September and was not surpassed before 26/3 last year. [it must have been full moon, full sun and the water of the estuary reflecting the sun]

"Eco Build" the exhibition in Docklands, is becoming increasingly "corporate" and like a lot of Britain seems to be filling up with too may educated but ineffectual.

I tried to find out how long the watch battery in my Aurora inverter is likely to last, but the person manning the Power-One stand was in "what battery" mode.

Popped onto the Immersun stand, to try to get a feel for the kit, I don't think the person manning that stand had been selected to fill Martin Luther King's dream, "....content of character". Boredom saps everything - left with a leaflet.

Finally I failed to find "Energeno" on stand S2446 to see what was on offer in the "Wattson" area of excess energy consumption.

In passing I took a look at the "Solar Edge" panels and their individual " it is not an inverter it is an optimiser" black boxes. inside is the smallest most complex looking printed circuit board I have ever seen,

This is what it does:
The SolarEdge power optimizer is a DC/DC converter which is connected by installers to each PV module or embedded by module manufacturers, replacing the traditional solar junction box. The SolarEdge power optimizers increase energy output from PV systems by constantly tracking the maximum power point (MPPT) of each module individually. Furthermore, the power optimizers monitor the performance of each module and communicate performance data to the SolarEdge monitoring portal for enhanced, cost-effective module-level maintenance. Each power optimizer is equipped with the unique SafeDC™ feature which automatically shuts down modules' DC voltage whenever the inverter or grid power is shut down.

The MPPT per module allows for flexible installation design with multiple orientations, tilts and module types in the same string. When working with SolarEdge Inverters, SolarEdge power optimizers automatically maintain a fixed string voltage, allowing installers even greater flexibility with longer strings and strings of different lengths in order to design optimal PV systems. Alternatively, the new independent optimization (IndOP™) technology, available with OPA model power optimizers, allows power optimizers to be installed without the need for additional interface hardware and to operate directly with any inverter. The SolarEdge power optimizers are compatible with c-Si and thin-film modules and have a 25 year warranty.

Can anyone translate this for me into every day language, explaining how it works and what it does to enhance the PV installation to work as a more productive system?

Martyn1981

John_Pierpoint wrote: »

Can anyone translate this for me into every day language, explaining how it works and what it does to enhance the PV installation to work as a more productive system?

Hiya John, too complex to explain simply, but in brief, you end up with a string of power optimisers (PO's) rather than a string of panels. Each PO is connected to it's own panel.

So, instead of the DC travelling from one panel to the next and differences in shading, orientation, pitch (even panel make and model) having an effect, with PO's each panel just pumps its 'bit' into the PO string.

That way a poorly performing panel still contributes a bit to the pot, rather than acting as a brake on the whole string.

It then goes even further, since the system doesn't have to find an average point to work at for all panels, instead they all contribute at their max.

I'm starting to trust the hype, but, for a system that doesn't suffer much shade I'm not sure if the extra cost is worth it. PO's add about £40 each, but the inverters are a bit cheaper (maybe £200 less) as they are simpler. SE inverters are about 98% efficient, 12 year standard warranty, 25year warranty on PO's.

The crucial factor, is that you'll have an extra 16 pieces of kit (for a 4kWp system) up on your roof. They may have great warranties, but you'll still need to consider access.

This video explains it all. It links in to parts 2 & 3, about 10mins in total.

http://www.youtube.com/watch?v=lsa9rHpDVmQ

Mart.

Oscargrouch

John_Pierpoint wrote: »

Never mind cat heating - dog heating has an antique heritage


Explanation:
les affuteurs travaillaient allonges avec un chien sur le dos pour leur transmettre un peu de chaleur car les meules etaient actionnees par l’eau très froide de la rivière. Avec l’image je comprends mieux.

Can anyone translate this for me into every day language, ?

The sharpeners were elongated with a dog on the back to convey a bit of heat because the wheels were actuated by very cold water of the River. With the image I understand better.

Dave_Fowler

One advantage mentioned in the blurb about the Solar Edge system is that it can operate with a mix of panel types. Should a panel fail or be accidentally damaged in, say, 15 years' time you won't have to find an exact replacement. In 15 years' time no doubt things will have changed a lot in the characteristics of the panels and 'antique' copies will probably be at premium prices.

Dave F

John_Pierpoint

Thanks Martin that was the eco /engineering babble I wanted translated; presumably there is enough "intelligence" in each black box for it to decide what to offer to a common wire part "full" of electricity flowing past, rather than act as a jammed water wheel in a ladder of such wheels ?

On another large "island" we were treated to the wonders of modern LED's.
From the sea of acronyms I think I extracted this message:

For the new builds "This is a science now, beware of buying cheap, because as the LED fades towards a loss of 30% you could very easily end up with a piebald effect", as intensity and colour rendition changes.
For retrofits "You can buy replacement "bulbs" for most fittings BUT you will notice that the life is about 1/3rd less than that of a purpose designed "luminaire" - you need to separate the electronic control gear from the LEDs. Trying to cram both on top of each other in a "bulb" leads to overheating. loss of output and premature ageing or failure".

I have a nasty feeling that the heat inside a black box, on a roof in the summer might upset its electronics.

===================================================

Thanks for the translation Oscar, just for the record here is Google's effort (a brainless method based on analysing millions of examples from the EU's need to produce instant translations into member languages)

Sharpening the extensions working with a dog on the back to send them a little heat because the wheels were driven by the cold water of the river. With the image I understand better

Here is mine:

A picture is worth a thousand words:
The cutler lies down on his front to grind the forged blank or sharpen the final blade (*). The dog has been trained to lie on the cutler's back, to offer a little warmth because the river water powering the grind stones is very cold.

(*) it is not clear if they are working as a team on a production line or on individual piece work; either way they need to keep their noses to the grind stone.

Martyn1981

John_Pierpoint wrote: »

... rather than act as a jammed water wheel in a ladder of such wheels ?

Oh John, John, John - I'm going to steal that sentence! So hard to explain the idea, despite the principle being pretty easy, then you go and nail it in one line. I tip my hat to you sir. :T

For some real world numbers, I've seen my 8 panel 2kWp WNW hit 1.2kW as the sun started to come round and on to it (last Aug). 1 panel practically touches the large chimney to it's SSW and was in total shade. Looking at the playback of actual wattage on the monitoring site, Slim Shadey (my worst panel) was putting out about 20W, whilst the other 7 were running at about 170W (+/- 5W) each. Without the PO's I'd guess that Shadey would have dragged the whole string down by 50% or so.

Slightly confusing, but since install in late July, this heavily shaded WNW system, is matching PVGIS climate as an unshaded system (allowing for Met Office anomaly differences against an average month). Obviously, PO's can only minimise shading, not magically remove it, so I suspect the higher than expected performance is down to the high efficiency of the SE kit, compared to the PVGIS site default losses. I'm not complaining.

[Edit: just me making this up, but the black box on the roof, might only be at ambient temperature, since it's hidden behind a thermal shield (PV). I think in the summer I'll pop a max / min thermometer out of the velux and behind a panel to see how hot it gets there. My little brain is struggling to guess what the result will be.]

Mart

John_Pierpoint

The following explanation, of the nose to the grindstone workers, is brought to you by Oscar & Microsoft "Bing":

the sharpeners were elongated with a dog on the back to convey a bit of heat because the wheels were actuated by very cold water of the River. With the image I understand better.

Once upon a time, my wife and I quaffed a carafe of free wine, in the company of the waitress, in a restaurant of the East German town of Bad Schandau. The town "controls" the gorge where the River Elbe, on its journey to carry the drains water of Prague to Hamburg, breaks through the mountains of the Czech border. Outside there was the mother and father of thunderstorms, so the three of us were only too happy to do some overtime correcting the menu.
The German menu had obviously been fed through something like the Google translator. It is not easy, were we trying to translate it into English or America? The restaurant was proud of its ability to cook "Zander" (fish) dishes.

http://www.gulliblestravels.co.uk/images/File0039.jpg

[I think I had better get back on thread]

EricMears

Late last night, all three weather forecast pages were agreed that I wouldn't see any sun at all today.
At 6:30am they still all said the same.
At 10am, one of them said it might be very sunny at 10am but none later. The other two said possible sunny intervals around lunchtime.

Using the new improved 'look out of the window' method, at 8am we had a very bright sky behind thin patchy clouds. By 10 am we had brilliant sunshine and with occasional short cloudy spells that continued till 4pm

We weren't alas generating very much at 10am - half an inch of snow on panels scuppered that ! However, continuing sunshine had cleared panels by midday.

Total for day (so far - @4:20pm) was 8.8kWh (aka 2 oranges + 1 satsuma) and every chance we'll creep over 9kWh before dusk.

9.08 kWh for the day

shafeeq

Considering the weather today I was pleasantly suprised to see the reading. It generated 8.26 kwh today. It the highest power of the year for short period today of 2.66kwh.. so roll on summer lol

tunnel

Well well well,thought today was going to be a whiteout,woke up to nearly an inch of snow and then the skies opened and out popped the sun.

It must have been the wind keeping the panels cool:rotfl: when we totalled 3.05"O"s or 12.2kWh

Very happy indeed:D