ᐅ Water-bearing fireplace connected to oil heating system (single-family home, older building) – costs?
Created on: 26 Aug 2014 12:40
U
Username_wahl
Hello, in the meantime we have looked at a beautifully maintained old building that we might consider as a new home.
The major drawback: high energy costs are to be expected.
Key data:
Year built 1930
200 sqm (2,153 sq ft) living area, 2 floors plus converted attic
Oil central heating 20 years old, 21 kW, operated at low temperature
(for 2 people, but we would be 5!).
Gas connection available!
Final energy demand is 289 kWh/(m²*a) (kWh/(m²*yr))! Energy efficiency class H!!!
That means, pessimistically calculating for 5 people, oil price increases, cold winter, etc., heating costs could be up to €3,000 per year!
My idea (and of course, before buying or renovating, we will get professional advice—this is just for brainstorming and rough cost evaluation) would be to install a water-bearing stove (masonry heater?) in the living room and connect it to the central heating system (with heat storage, control, domestic hot water heating (except in summer?), and later the option to connect solar panels etc.).
There are 2 existing fireplaces.
Since my parents own forest and equipment for harvesting wood, we would get the wood “almost” free of charge (of course, labor, transport costs, equipment operation costs, etc. would apply).
What would a renovation like this roughly cost if carried out by a specialist company?
How high would the (additional) operating costs be, including maintenance, etc.?
What energy/cost savings could be expected, and when would the investment pay off?
Would it be possible to get a government-subsidized loan such as a KfW credit?
How would the calculation change if a solar system for domestic hot water (in summer) were installed at the same time?
Does the new energy saving law then require a full renovation of the house (insulation, etc.)?
What would be the alternatives?
The major drawback: high energy costs are to be expected.
Key data:
Year built 1930
200 sqm (2,153 sq ft) living area, 2 floors plus converted attic
Oil central heating 20 years old, 21 kW, operated at low temperature
(for 2 people, but we would be 5!).
Gas connection available!
Final energy demand is 289 kWh/(m²*a) (kWh/(m²*yr))! Energy efficiency class H!!!
That means, pessimistically calculating for 5 people, oil price increases, cold winter, etc., heating costs could be up to €3,000 per year!
My idea (and of course, before buying or renovating, we will get professional advice—this is just for brainstorming and rough cost evaluation) would be to install a water-bearing stove (masonry heater?) in the living room and connect it to the central heating system (with heat storage, control, domestic hot water heating (except in summer?), and later the option to connect solar panels etc.).
There are 2 existing fireplaces.
Since my parents own forest and equipment for harvesting wood, we would get the wood “almost” free of charge (of course, labor, transport costs, equipment operation costs, etc. would apply).
What would a renovation like this roughly cost if carried out by a specialist company?
How high would the (additional) operating costs be, including maintenance, etc.?
What energy/cost savings could be expected, and when would the investment pay off?
Would it be possible to get a government-subsidized loan such as a KfW credit?
How would the calculation change if a solar system for domestic hot water (in summer) were installed at the same time?
Does the new energy saving law then require a full renovation of the house (insulation, etc.)?
What would be the alternatives?
U
Username_wahl27 Aug 2014 00:57I just noticed that the original post removed the information about oil consumption. It is approximately 2500 liters per year (660 gallons per year).
Passivhaus schrieb:
What would be the benefit of replacing the 20-year-old oil heating system? And if so, with what? The efficiency of modern heating systems is usually much higher than that of old boilers. In other words: you put in x amount of energy and only get back 20% of x as heat energy. With a newer burner, you might get back around 40%, saving energy and costs.
What to replace it with? Get advice from a heating engineer... You won’t find a solution for your specific house in the forum.
E
ErikErdgas29 Aug 2014 14:24Hello,
The starting point is a house from 1930, which may not be able to be energetically upgraded fully or only to a limited extent due to its design (possibly listed building protection – to be checked, other depreciation and funding options). Technologically, and therefore in terms of energy efficiency, the existing system is outdated. Unlike the current situation, there will be a future hot water demand estimated at 200 to 300 liters (50 to 79 gallons) per day for 5 people. It needs to be verified whether the stated final energy demand is based on a energy performance certificate or a consumption certificate; if it is a consumption certificate, the indicator is not suitable for further planning.
The first step is to determine the heating load and accordingly size the system. If a gas connection is available, it makes sense to convert to an energy-efficient condensing boiler that reliably supplies the building. Thanks to modern technology and the use of the condensing effect, savings of 20 to 40% are realistic. In addition, the oil tank and the regular refilling and maintenance will no longer be necessary. The hot water storage tank should be sized according to the future demand.
The wood stoves should be integrated into the heating system using water jackets since wood is available. This increases the cost-effectiveness of heat supply. However, the wood stoves should not be considered a fixed part of the heating system (what if there is back pain or tension with the parents — then no wood or only purchased wood). If applicable, the option to include solar support should be considered during planning if conditions permit.
There are funding options from KfW for all of this, either as a low-interest loan (Program 151/152, about 1%, up to €50,000 (about $54,000) per residential unit) or as a grant (Program 430, 10% on up to €50,000 (about $54,000) per residential unit).
The heating system renovation/optimization is a single measure that does not require other building improvements (e.g., insulation) to be carried out.
Best regards, Erik
The starting point is a house from 1930, which may not be able to be energetically upgraded fully or only to a limited extent due to its design (possibly listed building protection – to be checked, other depreciation and funding options). Technologically, and therefore in terms of energy efficiency, the existing system is outdated. Unlike the current situation, there will be a future hot water demand estimated at 200 to 300 liters (50 to 79 gallons) per day for 5 people. It needs to be verified whether the stated final energy demand is based on a energy performance certificate or a consumption certificate; if it is a consumption certificate, the indicator is not suitable for further planning.
The first step is to determine the heating load and accordingly size the system. If a gas connection is available, it makes sense to convert to an energy-efficient condensing boiler that reliably supplies the building. Thanks to modern technology and the use of the condensing effect, savings of 20 to 40% are realistic. In addition, the oil tank and the regular refilling and maintenance will no longer be necessary. The hot water storage tank should be sized according to the future demand.
The wood stoves should be integrated into the heating system using water jackets since wood is available. This increases the cost-effectiveness of heat supply. However, the wood stoves should not be considered a fixed part of the heating system (what if there is back pain or tension with the parents — then no wood or only purchased wood). If applicable, the option to include solar support should be considered during planning if conditions permit.
There are funding options from KfW for all of this, either as a low-interest loan (Program 151/152, about 1%, up to €50,000 (about $54,000) per residential unit) or as a grant (Program 430, 10% on up to €50,000 (about $54,000) per residential unit).
The heating system renovation/optimization is a single measure that does not require other building improvements (e.g., insulation) to be carried out.
Best regards, Erik