ᐅ New Single-Family Home Construction: KfW 40 Plus Standard – Infrared Heating or Heat Pump?
Created on: 19 Oct 2016 13:47
S
steffjay2kS
steffjay2k19 Oct 2016 13:47Hello everyone.
After several weeks of research and consultation, I have come to the conclusion that it would be best to gather some experiences and opinions directly from those who have already built their own houses. I will try to describe my construction project (starting in 2017) as detailed as possible so that hopefully you can help me a bit. Specifically, it’s about the question of which heating system I want to install:
The plan is a single-family house built with massive wood construction (using KLH - cross-laminated timber). As of today, we will also meet the KfW 40 Plus standard in terms of insulation. The energy certificate is in progress and will be provided later. The location of the plot is in 89**** near Neu-Ulm in Bavaria. Here are the floor plans first:
The building has 195m² (2100 sq ft) of floor area plus the garage, which of course will not be heated. The utility room is already marked, and there is no basement.
[ATTACH alt="neubau-efh-kfw-40-plus-ir-heizung-oder-Wärmepumpe-159242-2.jpg"]12164[/ATTACH] [ATTACH alt="neubau-efh-kfw-40-plus-ir-heizung-oder-Wärmepumpe-159242-4.jpg"]12166[/ATTACH]
Now to the known details regarding heating and building services. So far, we only have offers for infrared heating, which I have strongly favored up to now. But unfortunately, after more than two months of research, I realize that this type of heating is rarely recommended in various forum posts, etc. So I can only summarize the facts I have gathered and hope to receive any suggestions for improvement. And of course, corresponding advice comparing it to a heat pump:
- Decentralized ventilation system by Vaillant (approx. €4000)
- Domestic hot water heat pump by Waterkotte (approx. €3500)
- LG Neon bifacial photovoltaic modules with 10 kWp (approx. €21,000)
- Senec storage battery 12 kWh + accessories (approx. €18,000)
- IR heating elements from Digel-Heat (approx. €8,000)
The ventilation system and the domestic hot water heat pump are more or less mandatory if I want to meet the KfW 40 Plus standard. Regarding the infrared heating, it is clear right away that the heating devices themselves represent the smallest cost factor, while the photovoltaic system and storage battery are the major expenses. Which I don’t mind at all – after all, I would then be producing the electricity I need. Of course, the problem here is that no electricity is produced in the evening and in winter when it’s most needed... but that’s a fundamental discussion I do NOT want to start here.
Rather, I created an Excel spreadsheet for myself, listing the individual IR panels. I included rough usage figures (hours per day), noted the (fictional) heating period, and used a price of €0.29 per kWh. The heating period indicates that, for example, a panel would only consume electricity 50% of the time – so 30 minutes per hour. [ATTACH alt="neubau-efh-kfw-40-plus-ir-heizung-oder-Wärmepumpe-159242-6.jpg"]12168[/ATTACH]
Long story short: I arrive at an average heating cost of €287 per month – depending on the heating period, it can be significantly less. This calculation does not yet include the self-generated electricity from the photovoltaic system or the offset from feed-in tariffs for excess electricity produced. This should only be included to a limited extent here because I want to compare the actual costs without subsidies. And that is with a heat pump.
Hopefully, this is where many knowledgeable people from the forum come in: I have almost no experience with heat pumps so far. But can you a) understand the above calculation or see any major mistakes? and b) Can you roughly estimate the investment and running costs of a heat pump for the construction project described above?
Who has experience with the Senec storage system?
A somewhat longer text, but I hope you can help.
After several weeks of research and consultation, I have come to the conclusion that it would be best to gather some experiences and opinions directly from those who have already built their own houses. I will try to describe my construction project (starting in 2017) as detailed as possible so that hopefully you can help me a bit. Specifically, it’s about the question of which heating system I want to install:
The plan is a single-family house built with massive wood construction (using KLH - cross-laminated timber). As of today, we will also meet the KfW 40 Plus standard in terms of insulation. The energy certificate is in progress and will be provided later. The location of the plot is in 89**** near Neu-Ulm in Bavaria. Here are the floor plans first:
The building has 195m² (2100 sq ft) of floor area plus the garage, which of course will not be heated. The utility room is already marked, and there is no basement.
[ATTACH alt="neubau-efh-kfw-40-plus-ir-heizung-oder-Wärmepumpe-159242-2.jpg"]12164[/ATTACH] [ATTACH alt="neubau-efh-kfw-40-plus-ir-heizung-oder-Wärmepumpe-159242-4.jpg"]12166[/ATTACH]
Now to the known details regarding heating and building services. So far, we only have offers for infrared heating, which I have strongly favored up to now. But unfortunately, after more than two months of research, I realize that this type of heating is rarely recommended in various forum posts, etc. So I can only summarize the facts I have gathered and hope to receive any suggestions for improvement. And of course, corresponding advice comparing it to a heat pump:
- Decentralized ventilation system by Vaillant (approx. €4000)
- Domestic hot water heat pump by Waterkotte (approx. €3500)
- LG Neon bifacial photovoltaic modules with 10 kWp (approx. €21,000)
- Senec storage battery 12 kWh + accessories (approx. €18,000)
- IR heating elements from Digel-Heat (approx. €8,000)
The ventilation system and the domestic hot water heat pump are more or less mandatory if I want to meet the KfW 40 Plus standard. Regarding the infrared heating, it is clear right away that the heating devices themselves represent the smallest cost factor, while the photovoltaic system and storage battery are the major expenses. Which I don’t mind at all – after all, I would then be producing the electricity I need. Of course, the problem here is that no electricity is produced in the evening and in winter when it’s most needed... but that’s a fundamental discussion I do NOT want to start here.
Rather, I created an Excel spreadsheet for myself, listing the individual IR panels. I included rough usage figures (hours per day), noted the (fictional) heating period, and used a price of €0.29 per kWh. The heating period indicates that, for example, a panel would only consume electricity 50% of the time – so 30 minutes per hour. [ATTACH alt="neubau-efh-kfw-40-plus-ir-heizung-oder-Wärmepumpe-159242-6.jpg"]12168[/ATTACH]
Long story short: I arrive at an average heating cost of €287 per month – depending on the heating period, it can be significantly less. This calculation does not yet include the self-generated electricity from the photovoltaic system or the offset from feed-in tariffs for excess electricity produced. This should only be included to a limited extent here because I want to compare the actual costs without subsidies. And that is with a heat pump.
Hopefully, this is where many knowledgeable people from the forum come in: I have almost no experience with heat pumps so far. But can you a) understand the above calculation or see any major mistakes? and b) Can you roughly estimate the investment and running costs of a heat pump for the construction project described above?
Who has experience with the Senec storage system?
A somewhat longer text, but I hope you can help.
Your photovoltaic system is expensive, costing over €2,000 (about $2,000) per kWp.
Infrared technology is interesting, but as you noticed, after one week of snow it becomes extremely costly—probably even sooner—12 kWh of heat are definitively lost...
Rough estimate:
Heat pump including domestic hot water around €20,000–25,000 (about $20,000–25,000).
Monthly costs up to €50 (about $50).
Infrared technology is interesting, but as you noticed, after one week of snow it becomes extremely costly—probably even sooner—12 kWh of heat are definitively lost...
Rough estimate:
Heat pump including domestic hot water around €20,000–25,000 (about $20,000–25,000).
Monthly costs up to €50 (about $50).
Photovoltaic systems are quite expensive. The storage capacity does not match the photovoltaic system and is even less economical when used with electric heating or heat pumps than it already is.
What is your motivation for spending an additional 40,000 euros on extra, unprofitable technology?
The difference between KfW 40 and 40 Plus is the technical package. The primary energy factor and transmission heat loss are the same. So buying a photovoltaic system and a storage unit to receive 5,000 euros more in subsidies… that can’t be the real reason you are considering this.
I find infrared heating interesting and haven’t read much about it yet. My first question is about its efficiency. The operating cost estimates you provided are certainly quite high.
What is your motivation for spending an additional 40,000 euros on extra, unprofitable technology?
The difference between KfW 40 and 40 Plus is the technical package. The primary energy factor and transmission heat loss are the same. So buying a photovoltaic system and a storage unit to receive 5,000 euros more in subsidies… that can’t be the real reason you are considering this.
I find infrared heating interesting and haven’t read much about it yet. My first question is about its efficiency. The operating cost estimates you provided are certainly quite high.
S
steffjay2k20 Oct 2016 13:30Thank you for the honest feedback. I probably should have mentioned that all previous considerations are aimed at the KfW funding: 2 units with a €15,000 (about $16,000) grant each, plus the 10,000-Houses Program from Bavaria. However, this requires a 12 kWh battery storage, which is why everything seems a bit oversized.
The energy performance certificates are currently being prepared and will, of course, be included in the comparison... but as I wrote at the beginning, I just wanted to gather some opinions on what other home builders are choosing.
The energy performance certificates are currently being prepared and will, of course, be included in the comparison... but as I wrote at the beginning, I just wanted to gather some opinions on what other home builders are choosing.
Similar topics