ᐅ Your current heating consumption

Soroka schrieb:
There is no KfW rating because it was built without it.

That means "house according to the Energy Saving Ordinance" and, together with the year of construction, provides some information. However, it could also be a highly insulated house without KfW financing. It depends on what you wanted to say.

I didn’t mean to imply anything. I was just referring to the primary energy demand of 99.6 kWh/(m²a). Regarding the room temperature, I actually start to feel uncomfortable at 21°C (70°F)…

Nordlys schrieb:
It’s quite interesting to see the consumption of a good old oil heating system. Heating system from 2000. Heated area 430 sqm (4,631 sq ft), of which 130 sqm (1,399 sq ft) is residential and the rest is commercial or used otherwise. House from 1979, double-walled construction, later upgraded to triple glazing. Annual consumption in 2016 was 6,078 liters. The price was 3,000 including tax. That’s 3,000 divided by 430, roughly 7.10 per sqm. Progress is therefore very slow.

I don’t really see what’s so great about the oil heating system. With the oil heater, you generated roughly 60,000 kWh of heat (how efficiently that heat is delivered inside the rooms, I don’t know). With my heat pump, it would have cost me about a thousand less overall compared to your oil system. However, converting from oil to a heat pump wouldn’t pay off due to the investment cost when replacing the system. Still, I doubt that burning finite resources is a sustainable path forward. Economically, it might make sense, though.
By the way, progress is economically hindered mainly by government policies.
If you look at government charges, you’ll notice that for oil, the taxes and fees are 1.44 cents per kWh of energy, while for electricity, the share is about 12 cents per kWh, so you pay roughly eight times more taxes and surcharges on electric power. If electricity were taxed at the same rate as oil per kWh, heating with a heat pump would be considerably cheaper than using oil.

It’s not about oil. It’s about a house from 1979. That’s what I mean when I say progress is slow. Because six thousand liters (approximately 1,585 gallons) is actually reasonable for 430 square meters (4,630 square feet) as annual consumption. Oil has already cost nearly one euro per liter, and its price is very volatile. I wouldn’t choose oil anymore for a new building and won’t do so. However, in a new build, we will hardly be able to cut our heating costs in half.

Hello,

Saruss schrieb:
I don’t really see what’s so great about the oil heating system. You generated around 60,000 kWh of heat with the oil system. With my heat pump, it would have cost me about a thousand less than your oil.

I’m not quite following your calculation:
You say your heat pump can produce 60,000 kWh of heat for 2,000 €?
A quick calculation: for 2,000 €, you can get about 8,000 kWh of electricity. That would mean a seasonal performance factor (SPF) of 7.5. To achieve that, you’d probably need a coefficient of performance (COP) around 9 to 10 on average over the year.
Either you found a way to get cheap nuclear power from France, or you have a perpetuum mobile as a heat pump, or you’re tapping into a geothermal source…

Realistically, I would estimate the electricity consumption of a heat pump for generating 60,000 kWh of heat at a minimum of around 15,000 kWh. That would put the cost closer to 4,000 €...

Or am I missing something?

Best regards,

Andreas

Just a quick note: My heat pump actually operates with a seasonal performance factor (SPF) of over 6 (total electricity consumption of the heating system, including domestic hot water and pump electricity), since in recent years my flow temperature only had to exceed 30°C (86°F) for a few hours per year (!). I had my house and borehole generously sized, and it was never extremely cold for long periods—at 0°C (32°F), the temperature is significantly lower than that. So, about 10,000 kWh of electricity, which I would pay roughly 2,000€ under my heat pump tariff. However, I also know from other forums people who operate heat pumps (naturally not air-source) with similar seasonal performance factors in much colder regions, for example in Switzerland.

Of course, it looks different with a less favorable overall concept or higher electricity prices.

The consumption mentioned is obviously very good for the size and age of the building. However, if there is commercial use or craft workshops in the rooms, or many computers, other energy sources may need to be taken into account. (For example, if there are 30 computers, that can quickly add several kilowatts of additional heat.)