3 votes

OK DP: Here is my problem - what is your idea?

How would you like to be handed the best present ever, a toy you have dreamed of for decades... and now it falls into your lap but you can't get the ribbon off.
There is a rumor that I am fond of hot springs. Well, one did not quite fall into my lap, and I did not quite fall into it, but I find myself in an amicable, working relationship with people who own a 160 degree (F) artesian hot spring, pumping over 100 gallons per minute.
All those things that just came to mind - they've done that. These people are NOT stupid. Whatever remains of "sleep" in their eyes is clearing a little more each day, and they were never stupid. The pool and soaker tub are LOVELY, everyone in the RV park / campground / trailer court is offered free geothermal heaters. There have been greenhouses here 3 times in the past, but wind and fire leveled them. There is a rumor about some aquaponics greenhouse dome project in the works... I'm sure I don't know anything about that. :)
They are willing to - correction, EAGER to - utilize this resource in any way they can, as long as it does not harm the resource and with the desire to share the resource with all who help. It is not a commune, I pay rent and if I quit paying rent, I will be evicted. It took me a while to trust them enough to do this, but thankfully, my ego finally bowed out of the discussions (I wanted it on MY land... Me, the one who really does know that the earth owns me, not vice versa...)
So, nothing personal, but I took the problem to permies first. They have a whole section about alternative energy, and this is not like "zero point" stuff. The water is hot, trust me. Or don't trust me, jump in, but do have your will made out before you do. I got turned onto Organic Rankin Cycle technology. Yep! That is the answer! But... they come in smallish size for sources 180 and up, and they come in mega-industrial size for lower temperature sources like ours. So, if you are not familiar with this technology, check it out, it is interesting, I just don't see how to make it work. Maybe I am missing something... Do you see something I can do?
Our thoughts are returning to an old idea we had to try to rig wilderness hot soaks using cold water. Parabolic troughs heat water up pretty fast, we are thinking that if we start at 160, it should not require more than ten feet of well made trough to get it to steam. We are thinking having a rocket mass heater back up and make it all charge a high quality battery bank might be our best bet. What do you think? Any better ideas?
Mark and I both think the Sterling Engine might be possible, but we don't know much about them, just watched a few videos. If anyone knows how to apply this to our situation, I am all ears.
Another cool but apparently useless technology is graphene - do check it out. It is not available in any usable form right now, and I sort of have my hands full, I don't have the training, skills, inclination or time to invent a power system, I need to work with things that are already put together, or at least in kit form with "for dummies" instructions.
All leads are appreciated, but if anyone points me to a system I can use and afford... I'll name a holiday for you or something, I don't even know - buy you a hot soak and a beer, for certain! lol! (There is some budget, but not "industrial sized")

Trending on the Web

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Might be able to make a

Might be able to make a closed ammonia system...


The best use for hot water is heat, but....

I did see a story where someone used a hot spring to generate electricity. Basically it was a steam turbine, but instead of water as the medium they used a refrigerant that was superheated by their hot spring to drive the turbine. This refirgerant was then a liquid at room temperature. I think they had a ground loop to reject the excess heat and keep the refrigerant in a closed cycle. So my thought would be to do the electrci generation, and have the earth cooling loop below the greenhouse to reject the waste heat to the soil where it will be useful to grow your plants.

Absorption chillers can also use heat sources as low grade as 160F for the energy source for cooling as well. This is an old concept that has had some new work recently. There is a company called yazaka (or something like that) out of Texas that is working on coolers the correct size for an average house. I found this because I ran across absorption cooling and wondered if my solar hot water might be put to use in the summer to cool my home as well. It seems this would be a good use of the heat source in the summer as well.

Josh Brueggen
Jack of all Trades
Precinct Commiteeman Precinct 5 Rock Island Co Illinois

As a mechanical engineer, I second this way of thinking.

Fishy, you have a great free source of energy in the form of hot water. To efficiently run a Stirling or Rankin cycle, you need a large pressure differential which you probably don't have. This closed loop system could take care of that problem.

If you could cap the source and develop several hundred psi, you could run it through a water turbine to extract the energy from the pressure drop, then use the discharge to heat things.

Can I just use your brain for a while?

SOOOOO frustrating to know what kind of amazing resource I have access to, and have ZERO training or experience in anything remotely useful. I'll show all this to my husband when he gets home, he is MUCH more mechanically inclined than I.
I may be able to get some PSI, it is an artesian spring and it is a gusher... Thanks for the input.

Love or fear? Choose again with every breath.

Water boils at 160F at 4.7psig.

Low pressure, low temperature systems simplifies material requirements and lowers cost.

Free includes debt-free!


I'll see what I can chase down on this, sounds promising.

Love or fear? Choose again with every breath.

Thats a fair amount of fresh warm water

I would think the dome aquaponic application would be the way to go, maybe even a series of domes. Some electric energy could be captured from a turbine and generator from the water flow, that could be calculated. Trying to get the 160 degree water to the boiling point for a steam generator may require some expensive equipment and may not have the efficiencies of scale for the site. That rules out a conventional steam generator, but the sterling the right size may work. Good luck on your project, sounds like fun.


All the water needed to heat homes and the dome uses less than 15% of the capacity.
I guess I'm going to have to invent a wheel...

Love or fear? Choose again with every breath.

Focus on using the abundant heat. That low tech.

Making electricity requires substantial capital investment.

Since the Federal Reserve runs most research and development, practical small scale solutions are deep sixed.

Free includes debt-free!

Eh, maybe.

We have an idea that will require investing in about 10 feet of parabolic trough (which we know how to make pretty cheap), some black pipe and a steam engine. It probably won't make enough energy to power everything, but if we can do it once, residents could repeat it at each home.
I am stunned that there is nothing already available. I expected to find something we could not afford, but there is really nothing that is even designed for anything but industrial use, or tinker-toys for conversational value.
The low tech stuff is done, I tried to make that clear. These people WANT this resource used, heating homes, a public pool, greenhouse going in - all that uses less than 15% of the capacity.

Love or fear? Choose again with every breath.

Mother Earth News and DYI

These kids have fun building things and trying them.

The technology is out there.

Meeting this weekend
North American Model Engineering Society

Free includes debt-free!

The plan we are probably going to try first is from them.

We are going to try making a parabolic trough to get the water up to steam temp - learned how to make them from Dan.
I've toyed with the idea of inviting them up here, but that would mean using money from a miniscule budget on airfare. I think I will go leave a comment and see if they have any reply, though. Thanks.

Love or fear? Choose again with every breath.

it's over my head, and I've done a fair amount of . . .

study into alternatives--

but I wish you the best!!!

it's hard to be awake; it's easier to dream--


So you want a ready made, kit form, home energy system to utilize some natural resource to make energy for you and you don't want to learn everything about how to do it first? Sounds like you want someone to research all the options and offer a 'for dummies' solution.

Just checking.

Ok, well here goes. Rankine would work but you would have to boost the temp quite a bit and that would cost you more energy than it's worth in the end. Remembering the energy side of EROEI, you must receive more at the end than you put in along the way. Remembering the economics side of EROEI, the gain must be worth more than you paid to build it. Rankine with solar supplement doesn't fit that. It will cost you in automation, in electricity lost, in efficiency or in human work load... Take your pick but one way or another, you lose.

Your Stirling (note the spelling of the good Doctor's name) solution is viable. However, there's good news and bad news. The bad first, being that there are no publicly available designs that will get more than 0.2-1.0% of your available heat turned into electricity at any cost. At 1% of your 105 kW, that's only 1 kW.

The good news is that much better ones do exist. Because this option might get you up to 8% maximum efficiency, these will even economically justify adding both/either solar thermal or rocket stove heat boost/backup. The reason is that they could not only boost output but efficiency as well. Depending on budget, that could max out over 30%! However, due to the economic crisis and strong anti-support from all entrenched "energy experts", the developers are struggling with private funding at this time. If you really are serious about an inquiry, I might be able to put you in touch with them.

Yeah, if someone invented this wheel, I don't want to repeat it

It is not my area of expertise. I don't want to build my own washing machine, either. It may be that this wheel does not exist, or at least not in an economically feasible form. Asking is still free, right?
I don't know how serious I can be about an inquiry... if that means "money talks" I can whisper at them. I am very serious about trying to make it happen however I can, if that counts. It may be that I merely tilt at this windmill (alternative) for the rest of my life, too.
Funny that you were the only reply - another DP member said I should ask for your input, and I assumed you would not offer help to me. Being wrong is sometimes a wonderful thing. Thanks for that.

Love or fear? Choose again with every breath.