ᐅ Gas with solar thermal or heat pump? And possibly photovoltaic panels as well?
Created on: 18 Oct 2019 14:23
H
Hausbau129
Hello everyone,
We are a family of five building a solid-constructed house in southern Germany (160 sqm (1722 sq ft) living space + basement). Now we need to decide on the heating/hot water system. Since the question mainly concerns solar/photovoltaics, I hope this is the right place to ask.
We have chosen underfloor heating with gas. To meet the energy-saving regulations, an additional renewable component is required, such as a combination with solar thermal.
After consulting with the house provider, we have three options. Since I am unsure, I would be very grateful for some feedback on our situation.
Option 1:
Gas + solar thermal
Total cost: approx. €10,000
Payback period for solar thermal: savings of about €300 heating costs per year. According to the house provider, the solar system pays off in 15-20 years.
This seemed to me like a worry-free solution that works quite reliably.
Option 2:
Gas (only for underfloor heating) + separate domestic hot water heat pump Brötje BTW 300 (to meet energy-saving regulations instead of solar thermal)
The domestic hot water heat pump is installed in the basement equipment room and is intended to warm the domestic water using the ambient air in the basement.
Total cost: approx. €6,000
I like the low total cost. It is clear that we will have a higher electricity bill due to the heat pump. I wonder if the system produces enough domestic hot water for five people, especially if several shower one after another.
Option 3:
Gas + domestic hot water heat pump (like option 2)
+ photovoltaic system to partially power the heat pump with generated electricity
Total cost: approx. €15,000
Payback period for photovoltaic system: savings/feed-in tariff about €1,000 per year. According to the house provider, it pays off in 8-10 years.
The downside is of course the higher total cost. However, if you really "earn" or save €1,000 per year, that would be acceptable for me.
Question 1: Domestic hot water heat pump Brötje BTW 300
Does anyone have experience with this heat pump or similar systems? Does it produce enough hot water for five people? Are these systems mature and reliable?
Question 2: Photovoltaic system
So far, I haven’t really dealt with this topic because I thought it no longer made sense with the low feed-in tariffs. I do not want a battery. If any, just a photovoltaic system on the roof where part of the electricity is consumed directly and the rest is fed into the grid.
Would you currently still plan to install a photovoltaic system?
Question 3: Which option would you prefer?
We would like a system that requires as little maintenance as possible, is reliable, uncomplicated, and affordable.
I am very grateful for any feedback.
Best regards
We are a family of five building a solid-constructed house in southern Germany (160 sqm (1722 sq ft) living space + basement). Now we need to decide on the heating/hot water system. Since the question mainly concerns solar/photovoltaics, I hope this is the right place to ask.
We have chosen underfloor heating with gas. To meet the energy-saving regulations, an additional renewable component is required, such as a combination with solar thermal.
After consulting with the house provider, we have three options. Since I am unsure, I would be very grateful for some feedback on our situation.
Option 1:
Gas + solar thermal
Total cost: approx. €10,000
Payback period for solar thermal: savings of about €300 heating costs per year. According to the house provider, the solar system pays off in 15-20 years.
This seemed to me like a worry-free solution that works quite reliably.
Option 2:
Gas (only for underfloor heating) + separate domestic hot water heat pump Brötje BTW 300 (to meet energy-saving regulations instead of solar thermal)
The domestic hot water heat pump is installed in the basement equipment room and is intended to warm the domestic water using the ambient air in the basement.
Total cost: approx. €6,000
I like the low total cost. It is clear that we will have a higher electricity bill due to the heat pump. I wonder if the system produces enough domestic hot water for five people, especially if several shower one after another.
Option 3:
Gas + domestic hot water heat pump (like option 2)
+ photovoltaic system to partially power the heat pump with generated electricity
Total cost: approx. €15,000
Payback period for photovoltaic system: savings/feed-in tariff about €1,000 per year. According to the house provider, it pays off in 8-10 years.
The downside is of course the higher total cost. However, if you really "earn" or save €1,000 per year, that would be acceptable for me.
Question 1: Domestic hot water heat pump Brötje BTW 300
Does anyone have experience with this heat pump or similar systems? Does it produce enough hot water for five people? Are these systems mature and reliable?
Question 2: Photovoltaic system
So far, I haven’t really dealt with this topic because I thought it no longer made sense with the low feed-in tariffs. I do not want a battery. If any, just a photovoltaic system on the roof where part of the electricity is consumed directly and the rest is fed into the grid.
Would you currently still plan to install a photovoltaic system?
Question 3: Which option would you prefer?
We would like a system that requires as little maintenance as possible, is reliable, uncomplicated, and affordable.
I am very grateful for any feedback.
Best regards
L
lucciano-s12 Dec 2019 18:42guckuck2 schrieb:
Producing one kWh of electricity with photovoltaic panels costs about 4 cents. If you use it yourself, it also costs around 4 cents in VAT. Additionally, you forgo the feed-in tariff of approximately 10 cents per kWh.
So, ultimately, one kWh of photovoltaic electricity converted into heat by an electric heating element costs you about 18 cents.
One kWh of gas costs 5–6 cents, so about one third.
Photovoltaic electricity—sure, it’s a great option. But converting it directly into heat 1:1 would be unwise. It’s better to feed it into the grid, that’s where you make a profit. Thanks, I would use the electricity myself. Feeding it into the grid at the modest 10 cents isn’t really attractive.
I still find it difficult to understand how anyone can install gas systems nowadays... the costs will likely rise significantly, and it is simply a waste of finite resources.
And why not install photovoltaic systems? They can be financed separately under favorable conditions, and you ALWAYS make a profit with them. Plus, it’s good for the climate.
It’s really hard not to make a profit with them. Just leave out the storage and do a price comparison, then it works!
And why not install photovoltaic systems? They can be financed separately under favorable conditions, and you ALWAYS make a profit with them. Plus, it’s good for the climate.
It’s really hard not to make a profit with them. Just leave out the storage and do a price comparison, then it works!