What is more economical? Loading the buffer more often or reheating it?

Good day. I am interested in how to operate a buffer tank economically in combination with pellets, solar, and fresh water. Is it better to have higher holding temperatures, for example 75 degrees in the buffer at the top and bottom, and 50 degrees out? In this case, the boiler is often recharged (70-75 degrees) to maintain the minimum temperature of 75 degrees. Or rather higher lower buffer temperatures of 60 degrees out, which would then also result in approximately 75 degrees at the top. Then the boiler has to reheat more often (so 60 degrees out at both top and bottom). Can you give advice here? Thank you

The heat stays in the house in both cases. Therefore, it makes the most sense to focus on how the wood burns with as little loss through the chimney as possible. I guess that a long burning time is beneficial. However, the wood burners here would have to say more about that.

The heat remains in the house in both cases. Therefore, it makes the most sense to focus on how the wood burns with as little loss as possible through the chimney. I suspect that a long burn duration is beneficial.

However, the wood heaters here would need to say more about that.

Thanks.
So you mean rather increasing the upper buffer temperature so that reloading happens more often,
instead of heating up almost the entire buffer.
So rather keeping about 75 degrees at the top, and around 60 degrees at the bottom (which is sufficient for the underfloor heating).

And increase the hysteresis, you can also shower very comfortably at e.g. 45 degrees. If your boiler only heats to 70 degrees once a day, money is saved.

And increase the hysteresis, you can also shower very comfortably at e.g. 45 degrees. If your boiler only heats to 70 degrees once a day, money is saved.

But we want to run the fresh water at 60 degrees (at least at 58 degrees). There is supposedly a regulation that in a multi-family house 60 degrees (even for fresh water) is required... Our main concern is that no fluctuations occur.

That it is a multi-family house is only mentioned now. But since it is fresh water, you basically have no problems with Legionella.