We need a new version of this video. A lot has changed.

I need to do this

thanks EEVBlog… top boss.

What about battery backup —

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Comparing financial alternatives on the basis of payback is, to be very candid, the worst way to proceed. The most rational decision criterion for investments is net present value. That requires, however, that you identify the appropriate discount rate. In your case, it ought to be the rate of return from investing the same funds in the next best alternative. When I did all that carefully and in detail, I found that investing in domestic solar power generation would make me poorer.

Whoa, wait a sec. You buy at 28 cents per kWh, but they buy back at a fraction? What's wrong with the power you produce that makes it worth so much less?

Hi could you tell me why you didnt get a smart meter installed? Is there a reason to do this?

Dave, I went off grid 8 years ago using AGM batteries since that time I have learnt quite a lot about what is required for successful O cost in running a home solar generation and battery system. Because I wanted maximum power transfer capabilities using reasonable size CSA (cross sectional area) cables from the roof I opted for a nominal 48V battery system. 112V maximum with no load is transferred from the solar panel array which consists of 3 panels connected in series and 8 strings of these in parallel with a nominal 37-8V terminal voltage with no load and a maximum current of 8A full load. The potential difference across each panel (250W types) of course varies with load current. In my experience you don't ever obtain the manufactures power rating for the panels as it's based on max sunlight and optimal angle to the sun conditions. My house faces north with no shade from trees but of course the angle varies with the seasons.
The charge controller is a Victron 150/100 solar charge controller which charges up my battery bank which consists of 12V 280 ampere hour batteries connected as 4 parallel strings of 4 batteries connected in series. 1120 ampere hours at a nominal voltage of 48V, maximum being near 60V on onset of float charge. The battery bank is connected to a 48V to 230V 50 Hz inverter rated at 5000 VA. Depending on house system power factor I can attain near 4.6 KW or perhaps more depending if the house load becomes inductive or capacitive. Unlikely to become capacitive in any way but can become inductive with motors from freezer, fridge, washing machine, air conditioning (compressor loads) and fluorescent lamps being switched into the supply at various time during the day and night.
Leo Simpson from Silicon Chip asked me several years ago to write an article but as I was adding to the system over the years and had several failures using CHINESE garbage charge controllers and inverters I found I was still learning and didn't have a fully reliable system.
The Victron Dutch designed equipment seem to be reliable, I have learnt my lesson with trying to save a couple of thousand dollars or so using Chinese rubbish even though these devices were not cheap at the time. Some Australian companies imported cheap Chinese inverters then marked them up substantially, well that's my opinion anyway, I am still trying to repair two inverters with no hope of ever obtaining schematics.
On another note the reason why the phase voltage (250V or more in some cases) is so high from the grid is because local line transformers are being used for a task they were not ever designed to do, reverse feed. These are 11 KV to (415 line between phases) 240V 3 phase transformers meant to supply (step down) one way. The phase voltage goes up due to the multiple house inverters feeding then as a step up transformer, you can imagine the 11 KV goes up too.

Thanks for the video! For those watching from the US, check into your local utility company’s net metering program. If they participate in net metering they will buy your power back at a 1:1 ratio. A lot better than this 6cent rate!

5 years? Got to be for the physical panels right? For me, the labor for initial install and remove/reinstall (roof replacements) are several times to initial cost of the panels themselves.

Folk need to take a long term view. Tier 1 panels will still produce 80% of their rated output after 20 years.
Another consideration to factor into your figures is the ability to heat your home with heat pumps during the day instead of using expensive natural gas (price depending on where you live). This variable does complicate the payback a bit more. The extra savings consist of the gas not used minus the electricity not exported to the grid. Food for thought folks.

What's the payback for a system that you have to brush snow off the panels every day for 6 months?