Hello,
here I would like to share some experiences and data regarding my brine heat pump and deep drilling, based in part on the expert’s "questionnaire":
a) What is the soil composition on your property?
Up to 3m (10 feet) silty, fine sandy, clayey soil
Up to 4m (13 feet) slope debris, rock fragments
Then bedrock (mainly limestone)
b) How deep was the drilling?
Drilled twice to a depth of 72m (236 feet)
c) How much did the drilling cost?
€10,400 including double U-probes DN25
Grouting material with 2.0 W/mK thermal conductivity
Permitting process (building permit / planning permission)
Pressure-tight house entry at the basement and underground routing of supply lines (about 25m (82 feet))
Filling/draining equipment, filling, pressure testing, etc. (all inclusive)
d) How much did the system cost?
System: Tecalor TTc 05 with heating output at B0/W35 of 5.8 kW and coefficient of performance (COP) of 4.8
Cost: €9,800
e) Were there any difficulties during installation, if so, what kind?
Because the water used to flush out the drilled material during drilling seeped away, a "small compressor" was needed to blow it out with air. However, it had to be placed on a neighbor’s property who had not yet started building. The machine was the size and approximate weight of a 20-ton truck but was off-road capable. This caused a 2-day delay because the compressor first had to be transported to our site. No additional costs were charged.
f) How is the daily operation?
"Like a refrigerator." Once the parameters on the heating system are correctly set, the only thing that should be done is occasionally reading the information/data such as operating hours and source temperature. Otherwise, it runs "on its own," just like any heating system. When the door is closed, the unit is virtually inaudible. Very discreet since, apart from the cabinet in the utility room, nothing else is visible (all brine pipes are underground).
e) What are the operating costs for which living area?
Currently, a living area of 180sqm (1937 sqft) is heated, plus an additional 65sqm (700 sqft) of cellar space within the insulated thermal envelope (these rooms are around 15-16°C (59-61°F) on the coldest days). From September 2014 to September 2015, 2,000 kWh of electricity was consumed for heating and hot water (2 adults, 1 baby, 1 toddler). The house is a KfW-70 standard building according to the 2009 energy saving regulations, which already met the required technical standards before the central ventilation system with enthalpy heat exchanger was installed (we decided to add this after the initial applications).
f) to be continued ....
Note regarding the comparison of the coefficient of performance (COP):
Since optimizing the heating curve and settings at the end of last year, the system has had a COP of about 5.5. Operating hours are around 1200; the deep borehole was drilled approximately 20% deeper than initially recommended by the companies, at our own request.
here I would like to share some experiences and data regarding my brine heat pump and deep drilling, based in part on the expert’s "questionnaire":
a) What is the soil composition on your property?
Up to 3m (10 feet) silty, fine sandy, clayey soil
Up to 4m (13 feet) slope debris, rock fragments
Then bedrock (mainly limestone)
b) How deep was the drilling?
Drilled twice to a depth of 72m (236 feet)
c) How much did the drilling cost?
€10,400 including double U-probes DN25
Grouting material with 2.0 W/mK thermal conductivity
Permitting process (building permit / planning permission)
Pressure-tight house entry at the basement and underground routing of supply lines (about 25m (82 feet))
Filling/draining equipment, filling, pressure testing, etc. (all inclusive)
d) How much did the system cost?
System: Tecalor TTc 05 with heating output at B0/W35 of 5.8 kW and coefficient of performance (COP) of 4.8
Cost: €9,800
e) Were there any difficulties during installation, if so, what kind?
Because the water used to flush out the drilled material during drilling seeped away, a "small compressor" was needed to blow it out with air. However, it had to be placed on a neighbor’s property who had not yet started building. The machine was the size and approximate weight of a 20-ton truck but was off-road capable. This caused a 2-day delay because the compressor first had to be transported to our site. No additional costs were charged.
f) How is the daily operation?
"Like a refrigerator." Once the parameters on the heating system are correctly set, the only thing that should be done is occasionally reading the information/data such as operating hours and source temperature. Otherwise, it runs "on its own," just like any heating system. When the door is closed, the unit is virtually inaudible. Very discreet since, apart from the cabinet in the utility room, nothing else is visible (all brine pipes are underground).
e) What are the operating costs for which living area?
Currently, a living area of 180sqm (1937 sqft) is heated, plus an additional 65sqm (700 sqft) of cellar space within the insulated thermal envelope (these rooms are around 15-16°C (59-61°F) on the coldest days). From September 2014 to September 2015, 2,000 kWh of electricity was consumed for heating and hot water (2 adults, 1 baby, 1 toddler). The house is a KfW-70 standard building according to the 2009 energy saving regulations, which already met the required technical standards before the central ventilation system with enthalpy heat exchanger was installed (we decided to add this after the initial applications).
f) to be continued ....
Note regarding the comparison of the coefficient of performance (COP):
Since optimizing the heating curve and settings at the end of last year, the system has had a COP of about 5.5. Operating hours are around 1200; the deep borehole was drilled approximately 20% deeper than initially recommended by the companies, at our own request.
A crucial factor for the efficient operation of a heat pump is the planning of the entire system and its mode of operation.
With correct sizing and operation, I claim that a ground-source heat pump can achieve a seasonal performance factor (SPF) of 5, and an air-source heat pump an SPF of 4. This results in a difference or saving of 20%.
WOW, thinks the interested reader. 20% is quite significant. That’s true. However, when looking at the absolute numbers, it becomes more relative.
If the monthly payments decrease from 50 to 40€ (euros), that is an annual saving of 120€ (euros). Over 10 years, that amounts to 1200€ (euros), if I’m calculating correctly.
Everyone can continue calculating independently.
So, a tip for the original poster: with those prices, I would invest some money in the absolutely correct planning of the underfloor heating and the air-source heat pump. Then add photovoltaic panels. In a cold climate, I would raise the flow temperature slightly during the day to compensate somewhat for the cold period at night.
With correct sizing and operation, I claim that a ground-source heat pump can achieve a seasonal performance factor (SPF) of 5, and an air-source heat pump an SPF of 4. This results in a difference or saving of 20%.
WOW, thinks the interested reader. 20% is quite significant. That’s true. However, when looking at the absolute numbers, it becomes more relative.
If the monthly payments decrease from 50 to 40€ (euros), that is an annual saving of 120€ (euros). Over 10 years, that amounts to 1200€ (euros), if I’m calculating correctly.
Everyone can continue calculating independently.
So, a tip for the original poster: with those prices, I would invest some money in the absolutely correct planning of the underfloor heating and the air-source heat pump. Then add photovoltaic panels. In a cold climate, I would raise the flow temperature slightly during the day to compensate somewhat for the cold period at night.
Heat pump consumption database. You can see what is achievable there. It can be assumed that with good planning, a high annual performance factor can also be reached.
The monthly installments were just examples. Due to regional price differences, it can’t be done otherwise. Surely you agree with me that the heating load of modern houses will be in the range of 4–7 kW, depending on standards and size. Thermal energy demands of 20,000 kWh are no longer realistic here.
But let’s consider higher numbers: €70 monthly installment for a ground-source heat pump with a realistic annual performance factor of 5.
Air-source heat pump annual performance factor is 4. That’s 20% more per month, so €84. €14 × 12 months = €168 per year.
€168 × 10 years = €1,680.
This means, as it stands, over 80 years to break even.
After subtracting the costs for proper design and implementation, we are still in the range of over 60 years.
An expensive borehole simply isn’t worth it.
The monthly installments were just examples. Due to regional price differences, it can’t be done otherwise. Surely you agree with me that the heating load of modern houses will be in the range of 4–7 kW, depending on standards and size. Thermal energy demands of 20,000 kWh are no longer realistic here.
But let’s consider higher numbers: €70 monthly installment for a ground-source heat pump with a realistic annual performance factor of 5.
Air-source heat pump annual performance factor is 4. That’s 20% more per month, so €84. €14 × 12 months = €168 per year.
€168 × 10 years = €1,680.
This means, as it stands, over 80 years to break even.
After subtracting the costs for proper design and implementation, we are still in the range of over 60 years.
An expensive borehole simply isn’t worth it.
B
boxandroof28 Oct 2019 08:26The average wasn’t the point, but it still clearly shows what Joedreck describes: an annual performance factor of 3.4 for an air-to-water heat pump compared to 4.6 for a ground-source heat pump. Those who plan carefully achieve significantly better figures.
If I had a ground-source heat pump instead of an air-to-water system, I would save 70€ per year. The trench collector is economical thanks to subsidies, while drilling is challenging for modern houses with low energy consumption, even though it is the more elegant technology.
If I had a ground-source heat pump instead of an air-to-water system, I would save 70€ per year. The trench collector is economical thanks to subsidies, while drilling is challenging for modern houses with low energy consumption, even though it is the more elegant technology.
Similar topics