We have had our solar power installation upgraded from 3,000 watts to 6,000 watts of panels. The old panels are now 10 years old and have worked perfectly for the decade and still produce to their specification at midday. We were told to expect a 10% drop in output over the first decade of their life and then a steady drop-off in output for the next 25 years. There doesn’t seem to be any noticeable decline as yet. So we are really happy with them.
At the time we paid a little bit extra for them, to get Australian made PV panels, made in Sydney at that time. These have been faultless with 0% failure so far. This is not to say that any other panel wouldn’t be just as good. I don’t know, so I can’t say. However, it is our intension to support Australian industries and employ Australians wherever we can, so we paid the small extra premium for locally made product and that has worked out well for us so far.
On this principal, we decided to buy Australian made panels again. As I understand it, there is only one tier-one PV panel manufacturer here. ‘Tindo’ in Adelaide. They are still just 10% more expensive than the imported Chinese PV units, so I had no hesitation in choosing to employ Australians and support Australian industry once again. It isn’t worth saving $600 to put Australians out of work.
Over the decade the efficiency of the PV has increased significantly. The new panels are almost twice as efficient as the older ones, so the new installation is much smaller. 12 PV panels instead of 18.
We now have 6 kW of PV and we decided to buy a battery to store our own power and use it directly ourselves. Now that the solar feed-in tariff is so low and the price of green power is increasing, it makes sense for us to make the move. In fact we decided to do all this 13 months ago. It has taken Tesla over a year to supply the battery. We ordered the new Tesla PowerWall 2 as soon as it was announced. Tesla is good at advertising and self-promoting, but a bit slow to deliver. Anyway, it’s here now. It’s installed and working just as it should. The battery filled up on the first sunny day and has been powering the house since then. Once the battery fills up in the morning, it then starts to sell the excess back to the grid. Even today, when it is overcast and raining and the PV output is way down, the battery has filled up by early afternoon and we are now exporting again.
We bought our original PV array 10 years ago to extract ourselves from the coal economy, which we did. Now we are able to be independent from the grid. The new latest version of the PowerWall 2, has a built-in function to isolate us from the grid when it goes down. In the past the system shut down when the grid went down. Now we are able to stand alone and continue to run everything directly from the panels during the day, whenever there is sunlight, and from the battery at night. If there is a blackout, we won’t know about it.
We have enough power now to charge an electric car – at some stage in the future.