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Comment by 2Gkashmiri | Hacker News Reader

i have been thinking about getting a solar water heater>heat pump>radiator to warm up my home but the costs just dont make sense because of the heat pump. i am told the life expectancy of a good heatpump is like 10 years, that amount divided by only 10 winters it is expected to see is more than what we currently pay for electricity in winters, accepting that we don't currently have whole house heating, (we rely on personal hot water bottles/electric blankets in bed)

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My father works in that field. In his opinion heat pumps (with today prices and optimizations) are way overrated. The initial investment and the energy spent (it’s way more than advertised) doesn’t make sense for the average family.

i dont mind the energy spent on a day to day basis because i already have a 5.5kwh solar off grid array. i generate around 30 kwh during a good summer month and a fraction during winters but it gets offset from the grid also.

the grand scheme as i wrote above does not seem cost effective only because of the heat pump. if it were cheaper, i would definitely buy it because radiators/solar water/solar panels are low/no maintenance while heat pump does have it.

that can't be true. In Germany it is quite a trend now, but they are installed for many years. What I can read in the boards is not that discouraging. Where does this 10 year number come from?

https://www.racold.com/heat-pump-water-heaters

>Our heat pump water heater comes with a 2- years warranty and a dependable service for the inner tank.

this is like the premium heat pump contract manufacturer. good brand with a good reputation.

roughly 10 years is what the installer told me. refrigerators in india come with a 5+10 year warranty usually so this 2 year warranty is indicative.

The internet tells me that split-ac systems (basically small heat pumps) have a life expectancy of 10-20 years. That's not too bad, for example an oil-based heating system (as we have in our german basement) also only has a life expectancy of 20 years and has way less moving parts.

My oil based system is 45 years old but no part in it is the original one anymore, so with a certain maintenance cost spread over the years you keep it living indefinitely. Does the ship of Theseus concept apply also for heat pumps, or there you have to throw it away after 10 years?

Cost wise it only makes sense if you have photo-voltaic on the roof. In Germany there is more acceptance of paying more if there is a (possibly perceived) environmental benefit.

You can actually use an absorption heat pump that multiplies your solar thermal collector heat flux by 2~3 to lift outside ambient/ground source temperature to inside levels.

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