I had been running a 12V system with a 50W panel and a car battery. I tried to upgrade it to a 330W panel and ... well... I got the bug, just couldn't seem to stop.
Fast forward from Feb to today and I now have a fully off-grid office and gaming rig.
Off gird? If the power goes out, I won't notice. That's what I mean by off grid. Literally the AC connection to the mains is disconnected. Office, lights, monitors, PCs, speakers everything except the 24/7 stuff, runs off of batteries. 8 100Ah LifePO4 cells. Forklift batteries!
Right now I have:
3 x 330W CraigSolar panels. 41VoC 33VMPP, 11A SC (£230 each)
8 x 100Ah LiFePO4 battery cells. (~£280) (2.6kWh)
2 x Victron Energy MPPT 75/15 solar charge controllers. (£100 each)
1 x EPEver Tracer charge controller. (£100)
1 x Victron Energy Multiplus 24/800/16 Off-gird micro-grid inverter and transfer switch. (£550).
Cables, fittings, busbars, fuses, breakers, earth rod, consumer unit, RCDs, 1 day of electricians time and roof mount fittings for 3 panels.... probably about £500.
So, the two bottom lines. It's looking like upto 6kWh on a fully sunny day. 1kWh on rubbish days. That's between 41p and £2.46 a day in cost saving right now. I have 800VA to play with. 800VA is a bit like watts but is based on apparent power. The power the inverter needs to supply so the loads can consume the watts they do. As an example the HP ProDesk Mini PC + 1xSamgsung monitor = "low power mode" for when I'm actually working. That combo uses about 80W. However, the power factor is so bad the inverter is generating more like 130VA to provide the 80W. The inverter is limited to 800VA and it will only sustain that when it's cool.
In reality, an office full of LED lights, a 4K 43" HDR1000 monitor, a 21:9 34" ultra wide, Ryzen 5800X, Gtx3080, 32Gb while gaming all pulls about 600W max. Because I bought a nice corsair power supply it has power factor correction (or is just better) and when maxed out like that running Satisfactory or something the VA is only about 650VA. Much better than the Prodesk thankfully!
It should be noted, you can buy systems very simliar of Amazon for maybe £2500. They will not have the Victrn Multiplus though. That is a serious bit of "Off grid" kit.
In the mornings, assuming the battery is flat, the office is connected through to the grid. By maybe 9:30 or 10:00am the sun has lifted the battery voltage up a bit and the transfer switch opens and the inverter fires up to supply the office outlets. Usually by 11am the sun is overtaking the office load and rapidly charging the batteries while running the office daily and work laptop etc. When the sun goes down the office carries on running on the battery until it's flat.... rinse repeat.
If I don't game, it stays "off grid" overnight and doesn't bother with the grid. The gaming PC will eat battery for lunch and 2.6kWh is easily wiped out with a 2-3hour gaming sess.
When the battery is pulled too low the transfer switch drops back to the grid. You just don't notice this happening. Additionally, even though the inverter drops back to grid AC when the battery gets "low", there is a portion in reserve, such that if the grid fails, power cut, the inverter will fire back up to keep me powered until that reserve battery is gone.
Fast forward from Feb to today and I now have a fully off-grid office and gaming rig.
Off gird? If the power goes out, I won't notice. That's what I mean by off grid. Literally the AC connection to the mains is disconnected. Office, lights, monitors, PCs, speakers everything except the 24/7 stuff, runs off of batteries. 8 100Ah LifePO4 cells. Forklift batteries!
Right now I have:
3 x 330W CraigSolar panels. 41VoC 33VMPP, 11A SC (£230 each)
8 x 100Ah LiFePO4 battery cells. (~£280) (2.6kWh)
2 x Victron Energy MPPT 75/15 solar charge controllers. (£100 each)
1 x EPEver Tracer charge controller. (£100)
1 x Victron Energy Multiplus 24/800/16 Off-gird micro-grid inverter and transfer switch. (£550).
Cables, fittings, busbars, fuses, breakers, earth rod, consumer unit, RCDs, 1 day of electricians time and roof mount fittings for 3 panels.... probably about £500.
So, the two bottom lines. It's looking like upto 6kWh on a fully sunny day. 1kWh on rubbish days. That's between 41p and £2.46 a day in cost saving right now. I have 800VA to play with. 800VA is a bit like watts but is based on apparent power. The power the inverter needs to supply so the loads can consume the watts they do. As an example the HP ProDesk Mini PC + 1xSamgsung monitor = "low power mode" for when I'm actually working. That combo uses about 80W. However, the power factor is so bad the inverter is generating more like 130VA to provide the 80W. The inverter is limited to 800VA and it will only sustain that when it's cool.
In reality, an office full of LED lights, a 4K 43" HDR1000 monitor, a 21:9 34" ultra wide, Ryzen 5800X, Gtx3080, 32Gb while gaming all pulls about 600W max. Because I bought a nice corsair power supply it has power factor correction (or is just better) and when maxed out like that running Satisfactory or something the VA is only about 650VA. Much better than the Prodesk thankfully!
It should be noted, you can buy systems very simliar of Amazon for maybe £2500. They will not have the Victrn Multiplus though. That is a serious bit of "Off grid" kit.
In the mornings, assuming the battery is flat, the office is connected through to the grid. By maybe 9:30 or 10:00am the sun has lifted the battery voltage up a bit and the transfer switch opens and the inverter fires up to supply the office outlets. Usually by 11am the sun is overtaking the office load and rapidly charging the batteries while running the office daily and work laptop etc. When the sun goes down the office carries on running on the battery until it's flat.... rinse repeat.
If I don't game, it stays "off grid" overnight and doesn't bother with the grid. The gaming PC will eat battery for lunch and 2.6kWh is easily wiped out with a 2-3hour gaming sess.
When the battery is pulled too low the transfer switch drops back to the grid. You just don't notice this happening. Additionally, even though the inverter drops back to grid AC when the battery gets "low", there is a portion in reserve, such that if the grid fails, power cut, the inverter will fire back up to keep me powered until that reserve battery is gone.