Maybe these can pull 700 watts on a sunny day? And you’d need a battery to store it. Would likely make 50 cents a day or less in electricity, on perfect days. The cost for a battery, panels, and install would be ~1000 euro (or more if it’s a bureaucratic mess).
I just did some modelling with the help of claude (which can write 200LOC+ numpy code faster than I can)
300 Euros crappy setup, 600 euros mid-range setup, 1200 with storage. (Extra) regulations is zilch, it's legal to plug and play these things up to 800W nameplate capacity.
I went with numbers for mid-range, vertical south orientation and offsetting 200W (without battery, any overproduction is wasted). This nets you an avarage of €0.32 per day - With practically nothing in winter, and maybe up to €1 per day on a PARTICULARLY nice summer day.
But altogether, that still adds up to something like Eur 116 per year, so your midrange system earns itself back in 5-6 years.
Not great, not terrible. Nothing to write home about, but free money is free money.
I built one in Utah which is the only part of the US where it's currently legal, so I can give you the numbers.
- 4x Hyundai 435W Solar Panels @ 167$ each for $670 total
- 1x EcoFlow Stream Microinverter for $257.
- Various cables, MC4 crimping kit, etc.. about $150
Grand total was $1077, I set them in direct sun on my patio and have generated 6-8kWh per day. At Utah energy prices (0.12 where I live), they will pay off in about 4 years. Somewhere like California with 4x the energy prices as here, it would probably pay for itself in <1 year.
My 1kW southern facing setup produces a little less than three kWh a day, about 1000kWh a year. A have a battery too so I manage to use most of that energy myself.
I use a battery -- 6kWh, 3600W inverter, with 6x 440W panels -- and don't feed power into the house wiring, but simply power the appliances in the same room as the equipment: Starlink, Mac Mini with 32" monitor, 16" i9-13900HX laptop, half a dozen small SBCs (5-15W each), fridge, espresso machine, air fryer, microwave, toaster, kettle, 4kW (output, 900W electricity) portable air conditioner, dehumidifier (250W). some LED lighting.
At the moment (spring) in half-decent weather all the above stuff is 100% off-grid. I'm still using grid power for hot water heating, dish washer, clothes washer -- all of which I do for free in my daily "Free Hour of Power" -- and for intermittent incidentals such as the water pump (e.g. runs for 15 seconds when I flush the toilet) and lighting in usually non-occupied rooms such as toilet, bathroom, and bedroom -- which together means I'm paying around 10c-20c per day over and above the fixed daily charge.
