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Warning - this is a l-o-n-g posting, and picture heavy...

A few days ago I mentioned that we had some very exciting happenings at the farm.

Well, here is the news...

We have learnt a lot about our solar power installation through trial and error. When we initially installed our solar panels we were not informed about a number of things which were vitally important.  In this instance, we were not informed that low temperatures affect the performance of solar panels.

When the ambient temperature is below 10oC the cold affects the voltage of the panels - causing the voltage to spike.  We had all our 12volt panels (incorrectly) connected in series - all the way through to our charge controller. Connecting them in series meant that maximum volts were produced by the panels - which is what RMan was (mistakenly) aiming for.  (connecting the bank in parallel would mean the Outback charge controller would utilize the Amps produced, not voltage.)

We have an Outback 80 charge controller, which, translated that means it can handle an input of 80Amps and 145 volts power from the solar panels - maximum.

Our indoor Outback remote display gives us the
first /indication that all is not well with our
power production.
Silent - at 9.40a.m. in the morning -
is not good news.  It means the voltage
from the panels is spiking

What we discovered last year (winter) is that at sunrise, when the temperature is the lowest, the cold caused the panels to spike over 145 volts - the maximum the Outback charge controller could handle - which caused the charge controller to shut down.  For hours.  Which resulted in lost input charge to the batteries.

Checking in the power room, the Outback
charge controller tells the tale : 148VDC
High VoC = shutdown - to prevent damage
to the charge controller

Given the number of people world-wide who are off-grid and who rely on solar power to charge their storage batteries, I did not believe that the problem was unsolvable, so after contacting a number of people locally - who didn't help much - I went international.  An extremely helpful gentleman at Outback technical support in Australia, responded to my high voltage e-mail query. And, over the course of 16-odd e-mails [I told you you he was extremely helpful :) ], he advised us to reconfigure the panels.

Diagram of the new configuration of our 8 X
off-grid solar panels connected in series and
the two banks connected in parallel.

He suggested that we have two equal banks of panels linked in series, and then link the two banks in parallel with two breakers separating the two different guage cables between the panels and the charge controller.

Wiring into breakers
prior to being routed
through conduit

Breaker details

To do that we needed an equal number of panels.  We only had 7 (6 X 140watt and 1 X 135 watt).  Wayne, our SiL across the field, had two 140watt panels that he wasn't using, so we purchased them off him - thereby removing of the 135 watt panel from the exisiting array.  These 8 panels give us 1120 watts of potential solar power going to the Outback 80.

6 guys in the front and two guys behind -
installing our first 5 X solar panels in August 2012.

Plus, RSon had the very good suggestion of re-installing the solar panels in such a way that we would have available roof space if ever we wanted to install more panels in the future (our old existing installation "hogged" all the available space of over half the roof area).

But, that meant getting all the panels down off the 45° pitched roof.

You recall how the builders assisted us in installing the original five panels on the garage roof.  7 guys helped RMan that day.  Five in the front with RMan...

 ...and two holding support ropes at the back.

This time we only had RMan, RSon, Wayne and one of the locals we roped in to help.

I was fraught with fear.  Those panels are frigging heavy.  And the pitch of the roof is hectic - and not condusive to ease of clambering all over it.

The scaffolding was errected, and the removal proceeded at 11.00 a.m. on Saturday morning.  I was torn between not wanting to watch / document the event, but being aware that the more I photographed, the more info we would have if we ever needed to check something in the future.

RMan and RSon discussing the best way to handle
this enormous task - and RSon giving us an
idea for the addition of further panels in future

RSon, ever the adverturous one, elected himself to climb to the roof apex in order to connect the supporting ropes to the exising array.  And to loosen the existing bolts securing the solar panels to the roof...

RSon, Wayne and the helper trying to get the
panels off the roof

A couple of times I remember pointing the camera, closing my eyes and clicking the button.   I couldn't watch...

Since the first time we installed the panels, we have erected a carport roof - and that carport roof was in the way when it came time to secure the supporting ropes.

The carport roof was in the way, so we had to
secure the supporting ropes to a quaddie

 It was very hot and difficult work - with awkward access all round.

Removing the old cables so that we could get the
panels down

But, my fears aside, naturally they got the panels down in one piece, and without injuring anyone.  There is a God in heaven.

Checking and rwiring the panels and re-fixing them
to the horizontal aluminium square tube supports

We had purchased more cable with which to rewire the panels - and that was just as well. We discovered that one of the old cables had become pinched during the original installtion - and that was not good news!

As we are going to be installing the panels in a different configuration, the supporting beams inside the garage roof had to be moved as well.

The horizontal beams fixed to the trusseses
support the solar panels

(Ah - a small bit of news I forgot to give you - RMan managed to break his new-ish glasses a few weeks ago, and, although new ones are already on order, all close up work has to be done with his prescription sunglasses.

Inside a garage roof??!?!)

Wayne to the rescue again LOL

Oh, brother!!!!  The roof mounted bolts were
installed in the incorrect position

Once everything was rewired and refixed to the aluminium supporting structure, the first bank of 4 panels was once again hoisted up the scaffolding and onto the roof.

RSon at 5.59p.m. - perching like a monkey
 on the rooftiles in the fading light.
I definitely gained a few grey hairs watching him...
Does he know how long 9 months carrying a
child is, and what is involved in getting that child
to adulthood?????

All of this takes time.

They started at 10.30-ish in the morning and, at 5.59p.m. the first bank was more or less installed.  They had installed the securing bolts from inside the roof outwards.  Then trying to find the holes on the aluminium structure below the panels wasn't easy in the fading light - and it took ages.

So, Sunday morning the work continued...

Getting the securing bolt lined up with the hole
in the roof tile

The securing bolts for the second bank were installed from the outside in i.e. first through the aluminium square tube and then into holes drilled through the roof tiles.  Far easier.  Even given the raging gale that inconveniently sprang up to hamper the operation.

The new two banks of 4 X panels - using less roof
space than the previous installation - and producing
200 watts even in the cloudy weather evident on
the photograph.  This installation allows for a
further 8 panels to be installed in the future.

So, finally we have two banks of 4 X 140watt panels (which are connected in parallel this time) mounted on the roof again.

And - thanks to RSon's foresight, we have space to install a further 8 - 12 panels should we so choose in the future :)

Clever boy :)

The battery / inverter connections remain the same

So - there you have it.

The next day it was immediately apparent that there is a definite, and visible, improvement - 10 minutes after sunrise we are already getting a charge going to the charge controller and 30 minutes later over 300 watts is being produced.  With nada voltage spiking / shutdown occuring.  At the end of the day, we are obtaining 5KwH+ of charge to the batteries - in winter!!!! :) That we only achieved last summer.

And - there is no more over voltage spiking :D  So every scrap of power produced by those panels from the moment the sun hits them in the early morning to the last ray in the evening is now going to the charge controller and into the batteries.  Yipeeeeeeee!

Well done guys.  And, thanks - seriously - a very sincere and grateful thank you for all the work, willingness, thought and effort that you all expended to sort out our power problems.


By the way, tomorrow we will have been here for exactly 2 years :)  How fast the time has passed and how worth the move it was.  No regrets - neither RMan nor myself :)


P.S.  You have only 2 days left if you'd like to add your name to the piquanté pepper seed giveaway.  Entries close at 6.00p.m. on Monday, 30th June 2014 :)