Sessy home battery: is 1700W discharge power really enough?

This question came up surprisingly often during the product training sessions we were allowed to give on behalf of CHARGED (Sessy) at 4blue. And honestly? It seems like a legitimate concern. Until you look at the facts!

Many people think that a 1700W inverter is too small for a home battery, such as the Sessy. But in practice, it turns out that the majority of Dutch households rarely consume more than that. Two practical cases show: a 1700W inverter covers well over 80% to 90% of the consumption. This means the Sessy home battery is perfectly tuned to the daily energy demand of the average household.

What does a home battery actually do?

A home battery like Sessy is mainly used to:

• Absorb standby consumption

• Use solar power locally instead of feeding it back

• Increase self-consumption

• Increase autonomy

So it does not necessarily mean you need a huge discharge power. Rather, a smart, efficient control – matched to typical household consumption – is much more important.

Why 1700W is sufficient (in 2 real households)

Case 1: My own household

• Connection: 3-phase, 3x25A

• Annual consumption: ±6,500 kWh

• Fully electric: heat pump, electric cooking, electric car

• Result:

  In 82.2% of the time, the total consumption was under 1700W

Case 2: Household of “Mr X”

• Connection: standard

• Annual consumption: ±3,500 kWh

• Gas for heating and cooking

• Result:

  In as much as 93.5% of the time, the consumption remained under 1700W

These figures prove that the Sessy home battery is precisely tuned to the actual consumption pattern of Dutch households. Not to peak load, but to the daily reality.

Why a higher power is often overkill

A higher discharge power may seem attractive, but it also brings disadvantages:

• Higher cost of the inverter

• More conversion losses 

For maximising self-consumption, a compact system is often more efficient.

Smart design, smart consumption

The Sessy home battery is built for:

• Efficiency

• Ease of use

• Maximum self-consumption

Conclusion: 1700W is (for most) simply enough

A home battery does not necessarily have to be large, but smart and suited to your consumption. And that is exactly where Sessy excels. For the majority of Dutch households, 1700W discharge power is more than enough – this is proven not only by theory but also by practice.

Want to know more?

Then also take a look at this article that gives you more insight into sizing the home battery.