Switching to electric water heater from diesel burner

[Jameswiththefinca]

Hi everyone
Came across this forum and hoping there might be some friendly help out there for me.

We have been living on a Finca in Spain for 2.5 years now and have finally had enough of the old diesel burning water heater. To give you an overview... (I’m gunna do my best to give as much info as possible but I’m no expert, but that’s why I’m here!!!)

there are 6 houses spaced over about 1.5 acres which are supplied with hot water from a central hot water heater. The water heater is a Facody GT-23 diesel burner which is rated at 32,000 kcal/h. That feeds into a 1000L (about 265 gal) insulated water tank. The heater is starting to give up and I feel it’s about time to move to a more eco-friendly option. Was thinking of installing a 200-300L (2.4kw-3kw) electrical water heater powered by solar panels and basically installing that directly into the current system so I would still supply the hot water from the central location and pump it to the surrounding houses. I understand this is not the most efficient method, however we simply can’t afford 6 individual small water heaters and six individual installs.

so my questions are: does this all make sense? Is this a practical solution? Could I get away with a smaller water heater, say 100L, to cut down on the space and power requirements? Would you guys have any other options for me?

I would really appreciate any and all input to help me get my head around this. Thanks a bunch!

 

[Fitter30]

32,000 kcal/h = 126986 btu's = 38480 watts =38.48 kw since electric is 100% efficient your water heater 70-80%
80% = 31kw if my math is right

 

[Sponsor]

 

[Phog]

3kW is on the small side for even just one single household, let alone 6 households combined. (Most single-household electric tank water heaters have heating elements in the 4-5kW range).

It looks like the heat output of your current diesel burner is 35.6kW. This fits right in with fitter30's napkin math above.

http://www.gasfriocalor.com/images/caldera-facody-gt.pdf

So, only do this if you're looking to make all your neighbors hate you. Eco-friendly = big $$$. Perhaps see if there are gov subsidies?

 

[Jameswiththefinca]

32,000 kcal/h = 126986 btu's = 38480 watts =38.48 kw since electric is 100% efficient your water heater 70-80%
80% = 31kw if my math is right

Ooph ok... I guess you’re saying no then? Thanks for your response.

 

[Jameswiththefinca]

Thanks for your feedback. What if I look at it this way: how can I keep 1000L of water at a constant temperature of 50-55C while being constantly circulated? Maybe there is a calculation you can share with me to help me figure that out?

 

[Phog]

It's really difficult to say. 6 households can mean 6 residents or 24 residents sharing the hot water. Also need to know the length of the supply pipes, the heat losses through pipe insulation, the incoming water temperature, the usage profile (showers? baths?). The system you describe is actually a little smaller than what I'd expect to serve 6 non-connected residences. But you're in a warmer climate than I'm used to. Either way, it seems to be working as-is, so start there.

 

[Fitter30]

Purchase a hour meter same voltage and phase as your power wire it to the burner motor then track hours a day.
contact the heater you have manufacturer find out how efficient yours is how a new unit is and what they suggest. Ask for technical when you call or email.

 

[Jameswiththefinca]

Ok I see that this here is above my pay grade... Time to get in a plumber for his advice. Thanks for all of your help.