ᐅ How much energy does a photovoltaic battery storage system supply?

Hello,

my question is about an energy storage system.
Assuming it has a capacity of 6 kWh,
then theoretically I could run a 2000-watt (2 kW) fan heater for three hours, or three fan heaters for one hour.
But: does the storage system actually supply that much power?
Yesterday I was discussing this with a friend regarding a "barrel sauna" in the garden.
Is it possible to run this (4 kW) entirely on grid-tied battery storage (assuming the battery is fully charged), or does the storage provide only part of the required power and the rest comes from the grid?
I hope you understand what I mean with my question.

Thanks, Tom

The maximum discharge power is specified by the manufacturer in the datasheet.

Thank you, that term is exactly what I was looking for.
So, even with a full storage, it generally makes sense to do the laundry and run the dishwasher on sunny days when the photovoltaic system is producing the necessary electricity. Okay...

When charging and discharging a battery, there are always conversion losses.

Priority 1: Use electricity directly "from the roof"
Priority 2: From the storage system
Priority 3: From the grid

Hello, here is my energy balance for an actually very poor August so far. Our storage system has a capacity of 13.8 kW, and our garden sauna is equipped with a 9 kW heater. It is clearly visible that the storage cannot supply everything and, of course, is depleted very quickly when considering an average operating time of the sauna heater of around 3 hours.

Green: Photovoltaic production. Blue: Own consumption from the roof and storage. Red: Grid consumption

tommyboy schrieb:

But: does the storage actually deliver that much "current"?

Most batteries/storage systems are based on LiFePO chemistry, which can usually be discharged easily at 1C.
1C means the battery is fully discharged in one hour. For 6kWh of energy, that corresponds to a constant output of 6kW.

The problem, however, lies with the inverters. Many have a current limit that kicks in earlier.
High-voltage (HV) storage systems, on the other hand, can deliver high power output.

As mentioned before, you should check the datasheet for this.

AxelH. schrieb:

Our storage system has 13.8 KW, and our garden sauna has a 9 KW heater.

If the storage system has a power rating of 13.8kW, then of course it can easily supply a 9kW load.

However, you probably mean 13.8kWh, which makes this answer unrelated to the original question.
Especially since your chart does not even have labels.