NoRegretsCoyote
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I have a standalone garage with a flat roof about 15m from the house. I am thinking about solar PV for the roof and my rough calculations suggest maximum 2kWp.
Before I go any further it only makes sense if I can bring the power back to the house to take advantage of the feed-in tariff. There’s a cable that runs under the garden from the house that is about 10mm in diameter. Googling tells me that a cable of this size is safe for 50 amps or so. If I’m getting 2000 W at 220 volts that’s only about nine amps, so I’m guessing the cable should be well able to handle the power. Are my calculations way off here? Is there much transmission loss with this kind of set-up?
Otherwise the cable is anything between 10 and 30 years old. Is there any risk with something so old? The arithmetic changes a lot if I have to dig a new trench and lay an armoured cable of course.
Power consumption in the garage itself is minimal, an electric garage door and a few fluorescent lights. In daytime the power output of the solar PV should be enough to run these but what about at night? Can a system be rigged for the power to flow both ways? If not, would I need a small battery to power the lights and electric door?
Before I go any further it only makes sense if I can bring the power back to the house to take advantage of the feed-in tariff. There’s a cable that runs under the garden from the house that is about 10mm in diameter. Googling tells me that a cable of this size is safe for 50 amps or so. If I’m getting 2000 W at 220 volts that’s only about nine amps, so I’m guessing the cable should be well able to handle the power. Are my calculations way off here? Is there much transmission loss with this kind of set-up?
Otherwise the cable is anything between 10 and 30 years old. Is there any risk with something so old? The arithmetic changes a lot if I have to dig a new trench and lay an armoured cable of course.
Power consumption in the garage itself is minimal, an electric garage door and a few fluorescent lights. In daytime the power output of the solar PV should be enough to run these but what about at night? Can a system be rigged for the power to flow both ways? If not, would I need a small battery to power the lights and electric door?