Pellets with solar thermal or photovoltaic?

Hello

For the pellet boiler, I would always choose a thermal solar system. In combination with a buffer and cleverly chosen reheating times, there is no short cycling. I can’t imagine that an electrode direct heater powered by photovoltaics makes sense there. Both feed into a buffer from which the domestic hot water is also prepared. With the current 35% subsidy for biomass, 30% for solar thermal, and the possibility of KFW40 with a €24,000 repayment grant, it certainly makes economic sense.

I have had good experiences with Oekofen and Solarfocus products. The latter is also installed in our new building.

Olli

what is meant by the domestic hot water heat pump? I don't know the system

A small heat pump in the house on a separate water tank, which is powered by electricity. In this case, the pellet system does not produce domestic hot water but is only used for heating. Why do I suggest it? This way, you can turn off the pellet heating in summer and still do not have to limit the space for photovoltaics by solar thermal on the roof. It has already been stated that a normal heat pump is more sensible.

That was not meant like that. It just means that the house will be basemented either way and apart from a hobby room, only storage rooms and technical areas are planned there.
Therefore, it is not very relevant if the heating requires 2-4 sqm more because of a pellet bunker or similar. It simply doesn't bother me.
Groundwater is the problem, it only occurs after about 8 meters and the level apparently fluctuates as well. In the neighboring community, there have apparently already been problems with groundwater heating systems because of this.


A chimney will always be necessary because of a planned fireplace in the living room.

Is the performance of a photovoltaic system sufficient in summer to cover the demand of a heat pump? Or does electricity also need to be purchased?

Is the performance of a photovoltaic system sufficient in summer to cover the demand of a heat pump? Or do you still have to buy electricity?

I can count on one hand the days when it is not enough. Of course, water heating must be scheduled during the day.

The days on which it is not enough can be counted on one hand. Of course, the hot water preparation has to be scheduled for that day.

Last year, we had 2 days (March to October) when there were such severe storms and rains all day that not enough sun was available for hot water preparation. However, this is rather irrelevant - that amounts to about 0.40-0.50 euros loss per year.

How many kW of photovoltaics are installed then? With storage? And what is the output of the heat pump? How much buffer was filled with it or how many people are in the household?