ᐅ Hydronic Wood-Burning Stove, Underfloor Heating, Heat Pump, Photovoltaic System in New Construction?

orkan212 schrieb:
Why do I need a larger storage tank with a stove?

Can’t the stove simply heat the hot water tank of the air-to-water heat pump?

Hot water tank for domestic hot water or buffer tank for underfloor heating (is the latter even necessary otherwise)?

Do some research online on the topic – that way, you can answer my questions above for yourself and you will realize that it’s not just a simple “plug and play” connection and that you will need to invest a significant amount of money (which, of course, varies for everyone).

Hello,
the last post was some time ago, but maybe I can help based on my experience.
We have a water-powered stove from Olsberg, which according to DIN standards is completely room air independent, so there are no issues with ventilation, open kitchens, etc. The cost including the connection group (pump, controls, connection hoses) was 4200, the cost for the pipes including installation during the construction phase was 300. We also operate a solar system with 4 panels to support hot water in the summer. The storage tank holds almost 900 liters (240 gallons) and includes an integrated 200-liter (53 gallons) domestic hot water bladder. The whole house is 180 square meters (1937 square feet) with underfloor heating, plus a standard gas connection. Gas costs over the last 4 years ranged between 280 and 430 euros. Gas is mainly needed only during transitional seasons. We burn about 8-10 cubic meters (282-353 cubic feet) of wood per year. So, for us, it definitely pays off. Based on this experience, we are very satisfied. At the time, the choice was between this system or a heat pump, and this option was less expensive to build with excellent results.

Heating costs of more than EUR 1000 per year are not exactly low. This already leads to reasonable payback periods for heat pumps, assuming they are even more expensive than a gas connection and stove installation costing nearly EUR 5000.

Perhaps for comparison, here is our electricity consumption for our geothermal heat pump in the NRW region. The heating system has only been in operation since mid-November, as it was too warm before. In two months, we have paid about 250 euros for heating and hot water (a little over 1,000 kWh). With this, we maintained a living area of 250 m² (300 m² total floor area) at around 22 degrees Celsius (72°F) and were able to supply enough hot water for 5 people. Not bad for the first (half) winter.

This is intended as a sharing of experience for the original poster. However, I need to point out that an additional cost of 5000 euros is not accurate. A fireplace should be included anyway. One without a water connection also costs around 2000 euros because it is a special, truly room-air-independent fireplace. There are not many of these available, which is the crucial point. Additionally, firewood costs 40 euros per cubic meter (about 53 US bushels), so I spend approximately 750 euros per year. Now, comparing this to the additional costs of a heat pump, it is definitely more expensive since interest and repayment periods for the costs must be taken into account. Almost all calculations aiming to balance costs are based on paying for the system in cash, which is naturally much cheaper, but this is very unlikely in the context of a new build.

I really believe that you can only save money with a stove in a well-insulated new build if the wood fuel is free. My chimney cost me 3,300 and the RLU stove (not installed yet) will cost another 3,000 including installation and everything. For that amount, I could heat my entire house with gas alone for 10–15 years...

However, I want the stove mainly for the coziness and the look. We also considered one with a water jacket back then, but we came to the conclusion that it hardly pays off...