In for a penny,,,

Following my last posting on our solar panel upgrade and installation, I thought I should give you a peek into our new power room, which is located in the southern side (the cooler side in the Southern hemisphere) of our *new* garage :)  Our old setup with the 4 X 130Ah Deep Cycle batteries did what was required of it i.e. run the alarm when we were not here, and kept our little bar fridge more or less in working order.  But the batteries were too damaged to provide us with anything like the power we needed now that we are living here permanently.  

Inadequate power set up, comprising of
4 X 130Ah Deep cycle batteries,
distance from the solar panels to the
inverter was too far (= loss of energy
capture) and the Phocos 40 amp solar power
charge controller which was too weak to handle
the job we gave it. Seriously, we melted the thing!

We were using roughly 15.5 KwH / day in our town house or 465 KwH / month. That was costing us ZAR1.18 / KwH or ZAR625.52 / month (incl. V.A.T.).

With that in mind I took a snap of the Owl electricity monitor at exactly three months use (to the minute LOL - no, I'm not OCD - I just wanted to give you an apples for apples comparison, and "to the minute" was exactly when we arrived on the farm on the 29th June 2012.)

Our Owl shows that we :
are currently using 139 watts of power at 20.44h
the internal temperature is 16.5 oC
- and - most importantly,
we have used 150.88 KwH since we
arrived on the farm on the 29th June 2012

Here, being more aware of what power we have available, and ensuring that everything unnecessary is switched off / unplugged when it is not required / being used (that includes your iPhone charger, RMan! ;) ), we have, via our solar power, consumed 150.88 KwH in three months, or 50.29 KwH / month.  Which would have cost us ZAR59.34 month.  And 50.29KwH is roughly 10.54% of our normal monthly electricity bill.

Our Cotek 1000 watt inverter, although small,
is sufficient for now, but in hindsight we should've
purchased a 2000watt inverter.  All green lights =
input load is sufficient, battery charge is sufficient
and output load is good :)

With that calculation out of the way, I can now tell you that, at our current usage, our solar panels will be paid off, via our savings on our electricity bill, in 74 months (6.18 years) without any further electricity price hikes being taken into account.  And, bearing in mind that Escom wants to whack South Africans with a 15.11% price hike for the 2012 / 2013 period, I am hazarding a very safe bet that our panels will definitely be paid off faster than the 6.18 years.  From that moment on our power is "free-er" :)

As you can see from our new
Outback charge controller,
we currently have an input of
74.2 volts (8.7Amps)
and the output is 13.5 volts
(40.2Amps).
At 14.4 volts (the way I
understand it) the batteries "float"
i.e. they automatically equalize their
charge. You can also see the solar
panels have generated 1.8 KwH thus
far today (12.30p.m.) and the batteries
are currently being charged with 540 watts 

As far as replacement costs are concerned, the solar panels have a guaranteed lifetime of 25 years, and the 6 X 2volt batteries for 7 -10 years (depending on how you take care of them (top up the water when required, watch the output load, etc)).  When it comes time to replace these items, their costs will, hopefully, have come down quite substantially.  Solar panels currently cost ZAR11 - 14 / watt in South Africa for poly crystalline panels.  Apparently. those in the solar panel manufacturing industry are aiming to get the cost of solar panels down to below ZAR8.20 ($1.00) / watt!  

Our new solar power wiring diagram:
this photo illustrates how our solar panels
are connected to the charge controller
(not shown), and the 2 volt batteries
are connected to the Outback charge controller
and the Cotek inverter.  The yellow and orange
screw caps (floater things) on top of the
batteries indicate the health (water level) of the
batteries.

What we purchased was this:

5 X 135watt solar panels
6 X 1188Ah 2volt batteries which we have linked in series to give us 12 volt
1 X Outback 60Amp charge controller
and add all that to our existing 1000watt Cotek inverter 

We subsequently returned the 3 X 85watt solar panels which we had purchased for our neighbour, and which he didn't want, and exchanged them for another 1 X 135watt panel, which we are going to use in conjunction with the 4 X 130Ah Deep cycle batteries and a water pump - to occasionally, and when necessary, move the water from our rain water barrels next to the house, up to water storage tanks which will be located at the top of our property.  More on rain water storage later...

Our 6 X 1188Ah 2 volt batteries are wired in
series to make up the 12 volts we require.
Please note that this is how we were advised
to wire up our batteries.  Please check with
your local solar power agent regarding your
specific wiring requirements

Now, I realize that not everyone can afford to lay out a fair whack of money in order to get off the grid.  But, by taking baby-steps, savings are possible through investing in some solar powered lights - both for internal and external use), unplugging all those chargers which come with all those fancy new must have gadgets, switching off your power hungry hot water geysers and only switching them on for 1/2 hour prior to using them (or, if you can afford it, changing to a solar powered geyser), and ditching your electric stove / oven and using the sun to cook 95% of your meals :)

Which reminds me, my Sun Cook solar ovens order is on it's way from Portugal, so, not too much longer to all of you who have ordered one... :)