Thursday, November 19, 2009

What type of heat pump to choose? – PART 2

First step is to calculate how much specific heat loss your building has per square meter of usable floors (heat loss in W/m2). If your house has more than 60W/m2 maximum specific heat loss then I would not recommend installing heat pump. You should first think of additional insulation of the house. Typical house where heat pump is much recommended:

  • Net floor area = 150m2

  • Needed heat per year = 45kWh/m2 per year

  • Max Specific Heat loss 35 W/m2

To calculate heat loss you need a bit of engineering and mathematics, but I would recommend finding an engineer who has experience in calculating building heat loss. It also depends in what climate area you are living, what are your additional heat sources during the winter (solar roof, windows to the south…).

Saturday, October 17, 2009

What type of heat pump to choose? – PART 1

Winter is knocking on the door and I started my heat pump again. Since last post one idea occurred to me and that is answering quite frequent question: What type of heat pump to chose. I prepared relatively simple decision making model for choosing a heat pump for heating the house during the winter. Everybody knows that we have several types of heat pumps multiplied by number of producers and you can get 1000 of different heat pumps … O.K. it is not so bad :-) … actually we have few types of heat pump to choose between – in general: air to air heat pump, air to water heat pump, ground sourced heat pump (water to water). To be able to choose the right one you must consider: type of heating to be used, current/new building conditions, available heat sources, legislation, building restrictions, climate, heat losses, preparing also hot water, heating regime (low or high temperatures), and financial part.

In general one could say – every heat pump is better than no heat pump. But let us check in details in PART 2 … coming soon.

Tuesday, June 23, 2009

Parts and producers of my Heat Pump System

Few days ago I was moving around my heat pump and checking few things. I was wondering how many companies and parts are included in this heat pump system. I made a simple list of producers of most important parts of my heat pump system. You can check them also on the internet. Here it is:

Termotehnika – Slovenia (
Grundfos –Denmark (
Lowara – Italy (
Taconova– Switzerland (
Kovina – Slovenia (
AquaSystem – Italy (
AlfaLaval – Sweden (
ESBE – Sweden (
Austria Email – Austria (
Danfoss – Denmark (
Totraplastika - Slovenia (

Somebody wants to be a sponsor of this blog … be my guest :-)

By the way, my heat pump is operating during the summer only 20 minutes per day for hot water (300 liters of hot water).

Sunday, April 12, 2009

My Heat Pump Project Video

I've made a short video presenting my geothermal heat pump system on YouTube. In short presentation you can se the most important information about my system, some photos and links to this site. Thank you for reading and supporting my work.

Sunday, March 29, 2009

Detailed installation Schema for Geothermal Heat Pump Project

After receiving few questions about installing heat pump, connecting to the heating system and to the water heater, I decided to publish detailed installation schema. Here you can see every valve, pump, pipes, heat pump, water heater and other parts needed to operate the heat pump.

On the upper left corner of the schema you can see the legend for better understanding of the schema. I hope I didn’t forget anything – I cannot guarantee :-)

Electrical part of schema is missing (wiring) because I’m still working on it. Hope I will finish and publish it soon.If somebody finds an error in the schema please add a comment to this post. I case somebody have further question … please do not hesitate to post your comment.

Saturday, January 24, 2009

What was the investment in my Heat Pump Project?

I described almost everything but forgot to describe the most important :-). What was the investment actually? The majority of investment represents the vertical geothermal collector. One meter of geothermal collector (drilling + installing + testing + material) cost me about 50 Euro. Nowadays the price is higher. I have 220 meters of geothermal collector so it cost me about 11.000 Euro. Another high investment is heat pump, it cost me 3100 Euro. The total investment was 16.500 Euro.

Geothermal Collector = 11.000 Euro
Heat pump = 3.100 Euro
Water heater + pumps = 600 Euro
Pipes, valves, heat exchanger, other work = 1.800

I also received a subsidy of 2000 Euro for installing high efficiency heating system using renewable resource. So my investment was actually 14.500 Euro. If I would install oil furnace instead of heat pump the investment would be of course lower, but the operational costs would be higher (3 to four times higher). According to my calculations and simulations the cumulative costs (investment + operational costs (electricity)) of my heat pump would met the cumulative costs of oil furnace (investments + operational costs (oil + electicity)) in approximately 10 years. See also the Graph. This is I think called return of investment in 10 years – but I’m not economist so please excuse me.