diy solar

diy solar

Solar power to run natural gas in floor heat

Highway

New Member
Joined
Nov 18, 2022
Messages
5
I am new to solar and forums so please bare with me if I am out of line.
I am lucky enough to have a NG well on my camp property. I have generated electric and charged batteries with a magnum inverter charger and it worked well for some time but generator is older and looking for options. I have heated with a wall mounted unit for years but have pex in for in floor heat. I have a hot water heater and would like to start into solar to run only what is needed to run in floor heat. At least that is my thoughts. Can anyone help me with what I may need for this? Or where this kind of system may be found. Thanks
 
I am new to solar and forums so please bare with me if I am out of line.
I am lucky enough to have a NG well on my camp property. I have generated electric and charged batteries with a magnum inverter charger and it worked well for some time but generator is older and looking for options. I have heated with a wall mounted unit for years but have pex in for in floor heat. I have a hot water heater and would like to start into solar to run only what is needed to run in floor heat. At least that is my thoughts. Can anyone help me with what I may need for this? Or where this kind of system may be found. Thanks
So I'm new also, but I just learned about "dump loads" and using an electric water heater hooked up directly to the PV panels is possible (I believe). Your idea sounds reasonable to me.
 
Thanks for reply. I should have said the hot water heater will run from natural gas well. I need to know what it would take in the way of solar to run pump and turn on and off as needed.
 
Usually this starts with evaluating consumption. Both averaged out over a day and understanding when it happens during the day.

You can start with sharing the nameplate and runtime of all of the pumps.

One thing that can help with this is installing energy usage monitoring.
 
Thanks zanyroid. I may need to look around more. I don't have a system yet (no pumps) was looking for guidance if anyone knew of this being done and what components both solar and pumps, thermostat etc would be needed.
 
It sounds like you're trying to design two things.

1-Radiant in floor heating system using the tubing you already have in have in the floor and your gas water heater. What size is the tubing? How many feet per loops? How many loops? If your tubing isn't too small or your loops aren't too long you'll able to use a pretty simple circulator from Grundfos or Taco. It's a pretty basic system, just thermostat and pump.

2- A solar power system.
 
I need to know what it would take in the way of solar to run pump and turn on and off as needed.
I don't have a system yet (no pumps) was looking for guidance if anyone knew of this being done and what components both solar and pumps, thermostat etc would be needed.
I'm not sure if this is what you were asking exactly, hope it is helpful.
While there are several choices for DC powered circulation pumps that most likely would work just fine with regard to distributing the heat transfer fluid (water/glychol mix perhaps?) through the PEX hydronic heating loop, I'll bet it would be more difficult to find a complete control system that operates directly with DC from solar. Even if such products exist you would still need a some batteries to even out solar production during the day and for operation at night. Then a solar charge controller is also necessary to charge them properly. Once you've gone this far an inverter/charger would be a good choice.

From a practical point of view it makes much more sense to install a conventional hydronic control system and pump that operates with 120V AC. Not to mention, if the solar system is oversized a little then you have some extra 120V AC for other appliances. So as OzSolar points out, this project should be thought of as designing 2 systems that are related to each other.
1) It makes sense to start with the hydronic system and any other devices that you wish to operate on solar so a baseline electrical usage can be established. A variable speed circulation pump would be highly recommended in this situation.
2) Once the electrical demands are established then a sensible solar system can be designed.
 
With regards to dump loads, dumping into a water heater isn't the most efficient use of electricity, but it is more efficient than just letting it be unused permanently. It's use it or lose it with solar panel output unless you have a storage medium (either hot water or battery).

It is more efficient to store into a battery and then power a heat pump from the battery, but that has higher up front cost for the battery.

Maybe someone on the forum has a spreadsheet that maths out the break-even point between these two ways of heating water.
 
Thanks folks, yes you are correct I was thinking 2 systems.
1- in floor is 3 loops, 1/2" pex, 300' each.
2 - solar system. I was thinking simple 12 v with battery to run just this system.

I guess it makes sense to plan for some additional 120 v needs and future expansion.
My usage now is limited, fridge is gas so as few lights tv occasionally and 1 big item a 1/2 hp well pump. I usually just fire up gen. And fill 85 gal expansion tank as needed.
I will work on design of system and electrical usage needs. Thanks
 
Back
Top