Mick and Janet's  Photovoltaic Solar System.

Updated 9 Jan 2010

          Janet and I have a Photo Voltaic solar power system on our roof consisting of 10 x  BP4170S 170w panels and a GCI1700E (Sunnyboy) inverter.  The system was commisioned on the 6th of Jan 2005.  The supplier estimated it should generate an average of 2500Kwh per year based on our location and amount of daily sunlight (in Adelaide South Australia). You can see some photos from the Installation. 

Our systems performance..

 Our system has worked as expected since it was commissioned. The supplier estimated it should generate an average of 2500Kwh per year based on our location and average amount of daily sunlight. The table below shows the total amount of Kilowatts produced by the system. To date its over 12 megawatts.

*year in progress.

The graph below gives a monthly breakdown of how much power the system has generated. Jan 2008 was the greatest output month ever. It was the driest January on record for Adelaide. No rain, no clouds, just a month of blue skies.  April 2008 has a low total as the system was decommissioned on the 21st of April and it moved to Victoria. The system was reconnected to the grid on the 11th of August, so there is no data from May, Jun or July 2008. Feb 09 saw a lower than average reading, because of the bushfires that left the Victorian skies smokey for many days, reducing the amount of direct light hitting the panels.  In Nov 09 we moved back to Adelaide. The system was offline for 10 days during the decommission, move and reconnection giving the month a lower total than usual.

Solar Buy Back

To promote green energy systems, most states in Australia have introduced a generous buy back system for solar power that is exported to the grid. Solar energy that is produced by the panels is usually used by your house, but if you are generating more than you are consuming, the extra power goes out to the grid. The power companies in Adelaide buy this power back from us at a rate of $0.50 per Kw/h.  To accurately measure the exported power, the electricity wholesaler fits your house with a two way meter. It measures power that comes into the house, and also what goes out.  In our case on average about half of the power generated each month is exported to the grid. This is because during the day our power needs are quite low so we have excess solar power. 

The good thing about the buyback is the excellent rate that is paid. We pay $0.20 for imported power, but get paid $0.50 for exported solar. As a quick example, if we can export 4Kw/h during the day (4x $0.50 = $2)  we can import upto 10Kw/h (10x $0.20 = $2) from the grid and not get a bill. If we import less than 10Kw/h, we will have a power credit.  Naturally we try to reduce our power consumption during the day to maximise the power exported to the grid.   You can make a big difference to your power consumption by doing simple things like turning your computer when its not being used, and doing washing at night time rather than during the day. 

Relocating the Solar Panels.

    In 2008 I accepted a job transfer to regional Victoria, this meant Janet and I had to leave our home in Adelaide. Not wanting to leave the PV system behind, we packed up the panels and inverter and had them reinstalled on the roof of our Victorian home. The relocation process was relatively painless, but did take a bit of research. The hardest part was finding someone that would do the reinstall. Everyone was happy to sell me a new system, but helping to recommission an existing system was not high on anyone's priority list, especially when you live 3 hours out of Melbourne.  The panels were connected in the same configuration on the new roof. Two banks of 5 panels, but to prevent shading, they needed to be laid out in a single row across the roof.   In Nov 09 with the Victorian job complete, we packed up the panels and moved back to Adelaide.  

We would love to hear from others who have an interest in Solar Power.  Please Email us if you have any questions or info to share.

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