groar's solar panels thread

[groar]

During last two days, 3kWc of solar panels have been installed on our roof.

Edit: here is its monthly production since 2008/11/21:


Misc data :

• Surface : 23.37 m² (3.64 x 7.53).
• 25 poly crystalline panels of 120W (+/-3%) each.
• The irradiation is around 1428 kWh/m²/year.
• The panels should generate 3170kWh/year.
• Panels' efficiency is guaranteed at 80% for 25 years.
• The panels are used for watertightness of the roof.
• Aeration at top and bottom sides permit to cool down the panels.
• Panels organized into two strings (12/13)
• The inverter has 2 independent trackers to manage the two asymmetric strings.

The system has not been switched on as when connected to the internal network, the circuit breaker opens. It seams I have a problem on my internal network

Next step in a few weeks/months/... when ERDF, to whom I will sale my production, will connect to my inverter

Costs :

• Panels + inverter costs (material + install) : 22k€
• ERDF install cost : 600€
• Government aid : 8k€ in 1 year
• Sale price : ~0.57€/kWh, ie around 1800€/year
• Taxes : 60€/year to ERDF and 40€/year to government
• Inverter : 1500€ every 10years

The project should have paid for itself in 10 years.
Loan : 8k€ for 10 years at 2% : monthly payment = 75€

Notes :

• The high sale price is because the panels are integrated to the house, here they permit the watertightness of the roof. Else it would have been 0.33€/kWh. These prices are guaranteed during 20 years for all sale contracts signed before the end of the year. Next year, new contracts will be signed with sale prices gone down...
• The government aid is valid for all install done before end of 2009. It covers a part of the material price. For photovoltaïc it's 50% of the material price. This amount is limited to 4000€ by adult and 200€ by children. It's limited in time for the period 2006-2009 for all the ecological projects. In this single project we are using all our possible ecological government aid.
• The loan has a small interest rate as this is a "validated" ecological project, else it would have been 7%.

(unsorted) pictures are here : Album: install

Denis.

[Daox]

Nice install. I like how its integrated into the roof. Keep us updated on the progress.

BTW, what is ERDF?

[groar]

EDF (Électricité de France) is the governmental company producing and selling electricity. There exist a few other companies since a few years but EDF is always the main one.

ERDF (Électricité Réseau de Distribution de France) is the company who manages the distribution network of electricity, ie the grid. Its length is about 1.2 million of kms = 0.75 million miles. ERDF is currently a subsidiary company of EDF.

Currently I have a contract with EDF as a buyer.

To sell, I will have a contract directly with ERDF. They'll create a new connection from the grid directly to my inverter through 2 meters : one to count how much I sell and one to count how much I use from this line.

Denis.

[groar]

You know what ? I'm happy

ERDF installed his counters Wednesday and the panels' reseller connected the inverter to the counters one hour ago

So the counters are increasing... By now : 235 Wh in 53 minutes (weather is very cloudy) and I'm saving CO2 (400kg/yr) and uranium

A few additional photos later...
and I have to change my sig

Denis.

[Daox]

Awesome! Definitely keep us up to date on this.

[groar]

Two months (*) after the PV installation, ERDF (in fact private electricians mandated by them) came to install different counters :

Above from right to left :

• my consumption counter owned by EDF, not connected to the PV installation
• my selling counter owned by ERDF, with the telereport box on its right so they can ask the counters from the street
• my consumption counter owned by ERDF, with the main switch on its right

Under is a big box with big fuses inside. On that box is written 200A/60A.

(*) It seams that in my region half people installed during the 3 months before my installation are always not connected... so I will not complain about this 2 months delay.

Then Friday the inverter got connected to ERDF's system


and after a few minutes to pass the initial auto-configuration, the inverter was producing some electricity

(sorry for the poor quality of this photo)
Puissance sortie = Power out

The green LED and the 8 LED on its right are lighten proportionally to the production. At that moment only 265 W was produced, while the installation's nominal production is 3 kW, so only one LED was lit.
On the left of the green LED is a red LED which means the inverter isn't producing electricity when it's lit.

Here are more photos with captions : Album: connection in high resolution.

Next, the first figures...

Denis.

[groar]

Here are a few figures, noted this after noon (second day) during very cloudy weather :

• Power out : 122 W
• Total production : 1.719 kWh
• Day production : 1148 Wh
• Network tension : 233 V
• Network current : 0.88 A
• Network frequency : 49.98 Hz
• Network impedance : 0.3 Ohm
• PV Tension : #1 212 V / #2 197 V
• PV Current : #1 0.4 A / #2 0.3 A

Maximum values :

• Out AC : 677 W - 3.394 A - 238 V
• Entry 1 : 421 W - 1.835 A - 279 V
• Entry 2 : 396 W - 1.877 A - 260 V

I have 25 panels. One of inverter's entry has a string of 12 and the other a string of 13. Each entry has an independent tracker, maximizing current production from PV.

Next, the daily/monthly/yearly productions...

Denis.

[groar]

I will regularly update this message with :

• daily production until 2008/11/30
• monthly production from 2008/12
• yearly production once a year

I will also log my monthly production there :

You'll be able to see other pretty graphs there

Here is my daily production until 2008/11/30 :

• Wh : daily production (Wh)
• kWh(I) : Total production by inverter (kWh)
• kWh(R) : Total production by reselling counter (kWh)

Day   Wh  kWh(I) kWh(R)
21   571   0.571   0
22  1234   1.805   1
23  2370   4.175   4
24  3362   7.537   8
25   532   8.069   8
26   879   8.948   9
27  2366  11.314  12
28  4146  15.460  16
29   774  16.234  17
30  1984  18.218  19

Notes :

• 11/21: Sorry, It seams the board doesn't support the tables...
• 11/24: Fun, the total production reselling counter is going faster than the inverter
• 11/29: The reselling counter was displaying 17kWh while the inverter wasn't at 16 yet, ie a 6% bonus
• 11/30: 2008/11 (9.5 days) average : 1.9 kWh = 0h38 of 3 kWc and 53% of 3.6 kWh (November forecast).

Denis.

[Daox]

Ohh, daily updates. I look forward to it!

[groar]

Here is the forecast production for my PV solar panels system in kWh per month/day :

  Jan  Feb  Mar  Apr  May  Jun  Jul  Aug  Sep  Oct  Nov  Dec Year
   95  148  256  316  427  440  427  388  290  201  108   74 3171 cumulative
  3.1  5.3  8.2 10.5 13.8 14.7 13.8 12.5  9.7  6.5  3.6  2.4  8.7 average/day

From EDF's 2007 yearly report, here are the CO2 & radioactive wastes generated by kWh produced in 2007 :

• CO2 : 59.1 g/kWh
• long life (>100,000 years) : 0.9 mg/kWh
• short life (<300 years) : 10.0 mg/kWh

Looking at EDF's monthly reports, here are the CO2 generated in g/kWh :

  Jan  Feb  Mar  Apr  May  Jun  Jul  Aug  Sep  Oct  Nov  Dec Year
   81   68   54   57   45   43   46   33   55   61   36   47 2002
   63   61   46   58   40   42   50   51   54   56   44   42 2003
   42   49   63   52   45   46   38   45   43   34   40   45 2004
   49   73   69.4 52.8 33.2 41.3 51.7 28.3 44.9 50   55.8 71 2005
   68   75   62.5 22   18   31   46.5 31   44   42   44   48 2006
   42   41   49   57   45   34   35   28   44   59   68   63 2007
   49   40   44   53   27   42   33   24   45   61           2008

As you can see they are fluctuating a lot...
From a 2005 study, this is because they are mainly using coal power plant (900 gCO2/kWh) to reply to quickly fluctuating demand. While European average is at 340 gCO2/kWh, the French production can be separated by use :

• heating : 180 gCO2/kWh (129-261)
• lightning : 100 gCO2/kWh (64-151)
• intermittent use : 60 gCO2/kWh (38-93) (cooking, washing...)
• continuous use : 40 gCO2/kWh (20-72) (cold, cooling...)

Based upon EDF's 2007 yearly report, our 3kWc photo-voltaic solar panels should save :

• CO2 : 187 kg/yr
• long life radioactive wastes : 2.85 g/yr
• short life radioactive wastes : 31.7 g/yr

The reselling price is currently at 0.57187€/kWh, so the income for the first year should be around 1813€ (2284$ at 1,2595$/€).

Denis.

[groar]

I will not do it everyday, but I thought it could be interesting once.

Yesterday's weather was variable, but mainly cloudy. An average November day should generate 3.6kWh. Yesterday only 2.37kWh were generated.

The sunrise was at around 8h and the sunset at around 17h30. The inverter switched on at around 8h15 and began to produce at around 8h30, but the reselling counter didn't shown any instantaneous power before 8h45. During all the morning, the sun didn't appeared. Don't forget also that our PV system is toward the West and the sun can't see it before 10AM, so before that it's only the ambient luminosity that generates power.

 time WInv WRes DaWh OutA InV#1/2 InA#1/2 G/R
08h00    0    0    0                      0/1
09h00   25   20    9 0.62 197/183 0.2/0.1 1/0
10h00  105   80   70 0.89 210/193 0.3/0.2 1/0
11h00  227  250  216 1.41 213/187 0.7/0.7 1/0
12h00  379  410  498 2.14 233/220 1.1/1.0 1/0
13h00  416  440  944 2.23 233/216 1.0/1.0 2/0
14h00 1580 1680 1523 7.05 235/218 4.1/4.1 5/0
15h15   82   80 2197 0.87 205/188 0.3/0.3 1/0
16h00  175  150 2322 1.23 211/195 0.5/0.4 1/0
17h00    0    0 2370                      0/1

Where :

• time : clock
• WInv : Instantaneous W generated by inverter
• WRes : Instantaneous W received by reselling counter
• DaWh : Cumulative Daily Wh generated by inverter
• OutA : Instantaneous A generated by inverter
• InV#1/2 : Instantaneous V received by inverter in strings 1/2
• InA#1/2 : Instantaneous A received by inverter in strings 1/2
• G/R : Number of Green/Red lit LEDs

The instantaneous production shown on the reselling counter is updated less often than the one shown by the inverter, so the first is smoother than the second.
When the Red LED is lit then no production is generated as the power received from the panel isn't enough to generate some power. The Green LEDs correspond to power generated by inverter. Each LED is at most 400W, ie 1 LED means 0-399W, 2 LEDs 400-799W, 3 LEDs 800-1199W... But to switch a LED on or off, the inverter wait to have several consecutive measures in the corresponding range, so at 2PM there was 5 LED for only 1580W.

The new maximum values are :

Out : 1686W 7.801A 238V
In1 : 1029W 4.441A 279V
In2 :  949W 4.634A 260V

Bad, the In1/2 max values can be seen only when the inverter is switched on by panel power.

Denis.

[toyobug]

Denis, those figures are pretty impressive! I'm curious to see what a summer day would produce...
Keep them coming. Good Job!

[groar]

Updated posts #1 and #8 with the monthly production picture.
Post #8 has been daily updated with daily production from 11/21 to 11/30.

Denis.

[Daox]

Looks like your averaging around 2 kWh per day? Not too shabby. Do you think this is below or above average? I have no idea what the weather is like in your area this time of year.

[groar]

Originally Posted by Daox

Looks like your averaging around 2 kWh per day? Not too shabby. Do you think this is below or above average? I have no idea what the weather is like in your area this time of year.

1.9kWh is only 53% of the forecasted average of 3.6kWh/day in November. It's even lower than the 2.4kWh forecasted average for December.

As you can see in message #8, the daily production for November varies between 532 and 4146 Wh/day. Over 3000, the weather was mainly sunny. Under 1000, the weather was only cloudy.

But the day is short by now (9h11 for today) and any cloud is lowering the production a lot. In February it should be better

Denis.

[blueflame]

This is cool and really makes sense. I wonder if we can get a cheap loan in NZ for solar panels.

Imagine no huge distribution network of pylons, cable and switch stations but small scale producers everywhere.

People out of work could connect a generator to a bicycle, get paid and lose weight!

Imagine in the future every house putting wind generators on their roofs, people oversizing the installation to make more money...

Wish I had free electricity!