ᐅ Remove oil heating, install gas condensing boiler plus solar?
Created on: 18 Mar 2019 09:21
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Pianist
Good day to all readers!
Recently, as I do every two years, I attended the ISH trade fair in Frankfurt. After such an event, you naturally start feeling interested in new home technology. My oil-fired central heating system (Viessmann Vitola 200) is now 20 years old and runs perfectly; even the chimney sweep is satisfied with the readings. Objectively, there is no reason to replace it yet.
On the other hand, I consider myself a responsible person who likes to contribute to making things better. Last year, I replaced my diesel car with a natural gas vehicle, and I also switched to a genuine green electricity provider. Emotionally, I would definitely like to stop burning oil in the future, as I now regard it as almost unforgivable.
Gas supply is available in my street in a suburban area of Berlin. My roof shape is not ideal for solar thermal systems but also not completely unsuitable. It is a half-hipped roof with a north-south ridge, incorporating four dormers. I estimate that about 12 square meters (130 square feet) of collector area could fit on each side in the central section, but this would need to be examined more closely if I proceed.
The space currently occupied by the oil tank I would rather use for a private sauna and cancel my gym membership. I pay 1,000 EUR per year and rarely go due to lack of suitable time slots. The same applies to my father, so that would be about 2,000 EUR per year saved—enough to cover the cost of a sauna.
There would also be room for a sufficiently sized buffer tank. Another aspect is that my main workrooms are located in the basement, which tends to be too cold in summer. From April to October, I switch the system from heating to hot water only.
Now I am wondering: If I install a gas condensing boiler combined with solar thermal, I would ideally have enough hot water in summer and could warm the basement workrooms a little, while using little to no gas. In winter, my gas consumption would likely be less than my current oil use, since a new system would obviously be more efficient than my 20-year-old one.
The downside is that I have to consume gas as I buy it, and can’t purchase it when prices are low, unlike oil, which I can stockpile for over a year and buy when prices dip. Currently, I use about 3,200 liters (845 gallons) of heating oil annually to heat roughly 300 square meters (3,230 square feet) of living and usable space. That’s already significantly better than the national average.
So here is the big question: Is it sensible to switch now, or not? Will it actually improve my energy and cost balance? I assume I will have to switch within five to ten years anyway.
Thanks for all helpful thoughts!
Matthias
Recently, as I do every two years, I attended the ISH trade fair in Frankfurt. After such an event, you naturally start feeling interested in new home technology. My oil-fired central heating system (Viessmann Vitola 200) is now 20 years old and runs perfectly; even the chimney sweep is satisfied with the readings. Objectively, there is no reason to replace it yet.
On the other hand, I consider myself a responsible person who likes to contribute to making things better. Last year, I replaced my diesel car with a natural gas vehicle, and I also switched to a genuine green electricity provider. Emotionally, I would definitely like to stop burning oil in the future, as I now regard it as almost unforgivable.
Gas supply is available in my street in a suburban area of Berlin. My roof shape is not ideal for solar thermal systems but also not completely unsuitable. It is a half-hipped roof with a north-south ridge, incorporating four dormers. I estimate that about 12 square meters (130 square feet) of collector area could fit on each side in the central section, but this would need to be examined more closely if I proceed.
The space currently occupied by the oil tank I would rather use for a private sauna and cancel my gym membership. I pay 1,000 EUR per year and rarely go due to lack of suitable time slots. The same applies to my father, so that would be about 2,000 EUR per year saved—enough to cover the cost of a sauna.
There would also be room for a sufficiently sized buffer tank. Another aspect is that my main workrooms are located in the basement, which tends to be too cold in summer. From April to October, I switch the system from heating to hot water only.
Now I am wondering: If I install a gas condensing boiler combined with solar thermal, I would ideally have enough hot water in summer and could warm the basement workrooms a little, while using little to no gas. In winter, my gas consumption would likely be less than my current oil use, since a new system would obviously be more efficient than my 20-year-old one.
The downside is that I have to consume gas as I buy it, and can’t purchase it when prices are low, unlike oil, which I can stockpile for over a year and buy when prices dip. Currently, I use about 3,200 liters (845 gallons) of heating oil annually to heat roughly 300 square meters (3,230 square feet) of living and usable space. That’s already significantly better than the national average.
So here is the big question: Is it sensible to switch now, or not? Will it actually improve my energy and cost balance? I assume I will have to switch within five to ten years anyway.
Thanks for all helpful thoughts!
Matthias
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boxandroof18 Mar 2019 22:08ypg schrieb:
I think having an energy performance certificate would be helpful, so you have data you can use. Well, the consumption is probably already known. You probably mean an energy *consultant* 🙂
boxandroof schrieb:
Well, the consumption will be known anyway. You probably mean an energy advisor 🙂 Not bad either...
Let’s agree on getting professional advice 😉
Appointment with an energy advisor (thanks, @boxandroof) to know what options are feasible and at what cost if the system fails 🙂
Garten2 schrieb:
I'm just wondering – what kind of serious problems could have occurred there? Just google Staufen. However, it is a very specific type of ground.
Lumpi_LE schrieb:
You’re not entirely wrong, but the electricity isn’t lost in summer; it’s fed back into the grid and compensated. With the earnings, you then buy electricity again in winter. So, I basically have zero heating costs. What kind of profit? I pay 30 cents per kilowatt-hour and only get 11 cents for feeding electricity back. That’s a pretty bad deal...
If anything, only systems make sense where you consume the electricity you produce yourself. And that’s exactly where I see the problem: you have electricity when you don’t need it, and when you do need it, you don’t have any.
Matthias
The comparison really doesn’t make any sense... "I buy an apple for 30 cents, but if I grow and eat it myself, someone pays me 11 cents for it – no, that’s pointless." Without considering the cost of the apple tree and its maintenance, the statement has no value.
Without going into too much detail: for household electricity and heat pump electricity, I use about 5500 kWh. I can generate 2000 kWh myself and need to purchase 3500 kWh. The costs for purchasing roughly equal what I receive from the feed-in tariff – so effectively 0€ for heating and electricity costs.
Looking at it more closely, I end up with a few euros in electricity costs per month on average, but that doesn’t change the principle.
Ideally, it would be best if you could produce all your electricity in winter on your own – that’s possible too but less economical.
Without going into too much detail: for household electricity and heat pump electricity, I use about 5500 kWh. I can generate 2000 kWh myself and need to purchase 3500 kWh. The costs for purchasing roughly equal what I receive from the feed-in tariff – so effectively 0€ for heating and electricity costs.
Looking at it more closely, I end up with a few euros in electricity costs per month on average, but that doesn’t change the principle.
Ideally, it would be best if you could produce all your electricity in winter on your own – that’s possible too but less economical.
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Deliverer19 Mar 2019 10:52Pianist schrieb:
What kind of profit? I pay 30 cents per kilowatt-hour, but only get 11 cents for feeding electricity back into the grid. A pretty bad deal...You don't have to buy the kilowatt-hour you sell first. ;-)
Since solar panels have become cheaper, photovoltaic systems still make sense today. Of course, the faster the return, the more you can use the electricity yourself. (Air conditioning, pool, water heating between 12 and 14 hours...)