I have found the GEO 3 is the best for monitoring, it can tell me my generation from the PV system, home usage, what I’ve imported from the Grid and what has been exported. It has its own display which you can switch from Use, Import, Generation and Export.

Installed on the 14th April 2015
Solar PV System 1.44 kW on West facing roof.
Solar PV generation per year 1300 kWh.
My home has used a total of 2053 kWh in 181 days.
I have imported 1494 kWh so far this year.

>From in the setting tab I can download a CVS
file and workout what I’ve imported during day and what I’ve imported when the solar PV system is not generating e.g. at night time, it also gives you a breakdown in fifteen minute segments.

PV generated to date 837.0 kWh. I have used 558.9 kWh. I have exported (used in my immersion heater 278.1 kWh) I have used 66% of the solar PV generated kWh as self consumption so far this year.I expect this to rise to 75% consumption over the full year (975 kWh) out of the 1300 kWh as I’m not exporting much of the generated power to the immersion heater at this time.

Only down side is the cost at over £250 plus fitting, but can’t detect failure of individual panels.

Hope this helps

Andrew