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russ57:
I'm in Melbourne, Australia. I have 4.5 kW installed, flat, as Pk proposed above. My install is slightly unusual, in that each panel has its own micro inverter rather than a single large unit. I took this approach as I have some unavoidable shading, on a string install shading of one panel can reduce output quite considerably. The installation was dearer than the lowest tv advertiser, but they had actually refused to install a standard system a couple of years ago because - their - chosen location was too shady. (although cheap to install to)
The panels are now located on a much better position . Yesterday, a clear sunny (and hot) day I generated 25kwh, today 18kwh although it rained most of the morning.
I'm about to install battery storage, primarily because we have had 5 outages in the past month, not for economic reasons.

PK:
I reckon Micro inverters make a lot of sense, they significantly decrease a lot of the losses you get in a single inverter setup and give you more flexibility. We couldn't make a case for them in our setup, but they're probably cheaper now..

RodW:
I've got 7kW of panels feeding a 5 kW Sunnyboy inverter in Australia. The installer said that Sunnyboy would warrant the inverter at 7 KW input. I sent data to www.pvoutput.org for quite a while. Here is a graph of a really sunny day in October that produced 38 kW.

You can see that the daily output follows pretty much a "normal curve". (Google it if you are not a statistician). On this day, the maximum output was at the limit the inverter could handle. On really hot days, the inverter clips the output at 5 kW so you end up with a flat top on the middle of the curve.

You can see there is a bit of shade in the early morning that distorts the curve which is back on track by about 6:30. There was also a bit of cloud at about 2:30.

In my experience, a house has an idle power consumption that is consumed all the time . In my case, it is about 1KW. If you monitor consumption, you see this idle current consumed 24/7 with occasional peaks when you turn on a kettle or oven etc. Managing this idle current will have the biggest impact on electricity cost.

Anyway, I don't monitor the solar system anymore but hope this helps to visualise what actually goes on.

Oh and this madmodder used a Raspberry Pi to capture the data via a Bluetooth dongle from the inverter and for quite a while used a TV dongle on the Pi to capture power consumption (using some custom code) from an Effergy wireless power monitor and send both consumption and generation data to pvoutput.

DavidA:
Crazymodder,

As you are in Germany it seems as if your installation is more relevant to my inquiry than the reports from folks in Australia; though Canada is similar.

At the moment I'm only gathering data. My house faces south and a pretty much unshaded aspect is available for most of the daylight hours. I am interested in the grid tie from the point of view that when the sun is shining most (in summer) you don't need the power so much. So why not sell it back to the grid.

My main concern with any kind of Sun power is that we have had a lot of cloudy days over the last few months.

I may set up an experimental panel (maybe two, one a Sun tracker) and see what results I get before committing to buying more.

Does anyone here in the UK have them fitted ?

Dave.

chipenter:
I have a 24volt lathe and use two 12volt 8 watt solar pannels , the lathe motor is 32 watts and have only had to use the mains charger twice this year , eary March and last week even on a dull day they will put some charge into the two 70 amp houre batterys , before I fitted the pannels I was charging the batterys every two to tree weeks .

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