I'm looking to set up a solar power system for a machine that has rapidly changing power needs, fluctuating between 1kW and 5kW every 8 minutes. I want it powered entirely by solar panels, but meeting the 5kW output requires a lot of panels—like 21 of the 400W variety! However, if I incorporate batteries that can charge during the downtime and discharge during peak loads, I could significantly reduce the number of panels needed, possibly down to a 2 or 3kW capacity. The challenge is with the charge cycles being only 6 minutes long; if I use 1C rated batteries, I'd need to buy 10Ah for every 1Ah I plan to use each cycle. Are there any standard solutions or battery types specifically designed for this kind of rapid cycling? I'm looking for a balance between cycle lifespan, discharge rates, and cost. Some folks have referred to this as buffering or peak shaving, but I'm not sure about the specifics.
1 Answer
You might want to consider using two 100Ah 48V batteries. They should handle your 5kW peak just fine, especially since at full load for 8 minutes, you’re looking at around 700Wh per cycle. Just remember, if you’re running 5kW for 2 minutes and 1kW for 6 minutes, your daily consumption would be about 12.6kWh—which isn’t as high as it sounds for a solar setup!
Got it! So, really, if you only need the batteries to discharge for the high-load bit, charging them for 6 minutes with the solar providing 3kW is totally doable.