We’ve been facing some solar PV inverter issues with our solar PV installation lately.

It’s Broken!

It looks like the inverter (Fronius IG-30) has given up the ghost after 9½ years of loyal and reliable service to the Webber family.  It has provided us with many megawatts of clean energy for our pursuits.  As it stands today, there is no output from our system and it’s been that way since last Wednesday.

The inverter is the heart of any PV system.  It converts the Direct Current generated by the solar panels and converts it to Alternating Current in the form of 240 volts @ 50Hz to match the electricity grid.  Without it, the solar panels are as much use as a single chopstick.

I’ve sent off the fault to my system installer, Energy Matters, now owned by Sun Edison, to see what they can do about it.  Hopefully they can send out a specialist electrician to have a look and diagnose the issue.  If you want to know how the system has performed up until now, here is the link to a case study they did on our system a year or two ago.

16 x 175 watt Solar Panels. Currently useless!

However, I don’t hold up much hope.  From what I’ve read online, it is a major fault that requires replacement of the entire inverter, especially one as old as mine.  I also believe that it may be out of warranty so may be out-of-pocket for a considerable sum.

My Dilemma

So now I am faced with a dilemma.  Do I, a) Save up and buy a replacement inverter of the same type (3 kW grid tied), or b) investigate the cost of a hybrid system that incorporates a battery backup as well as export to the grid.

Why would I consider a battery option I hear you ask?

Well, the legislation here in Victoria that provides me with a generous 66 cent Feed-in Tariff.  It is due to expire in about 5 years, so at that time I will lose the offset against my power bill.

That means I should store some, or in time most, of the excess then export the remainder.

View from our gate

I figure that our evening energy usage will then be covered with stored electricity from the batteries.  Once the batteries are charged during the day, the excess will be just icing on the cake for the remaining years that the legislation remains in effect.  Once the legislation expires, I can bolt on more battery storage and keep it all, essentially being free of the grid.  Sounds like a better outcome.

Research Required

I do have some research to do before I make a decision.  If you know of a suitable inverter/storage solution, then let me know via comment and I will follow it up.  I don’t have a very big budget and if the hybrid system is too expensive, I will just have to replace the inverter.  Hopefully with one that I can bolt on storage at a later time.

Anyway, I’ll keep you abreast of the solar PV inverter issues in the spirit of knowledge sharing.  As the system was installed in September 2007, I consider us as early adopters.  I would expect that many other solar PV system owners will soon be faced with a similar decision as the one I do.

So, on with the research and may it be sunny!