Phase Change Materials in Thermal Storage

[LSaupe]

Are any of you using phase change materials in your thermal storage systems?

If so, could I ask what type and how well it has been working out?

Thanks and Regards,

Larry S.

 

[BrownianHeatingTech]

Are any of you using phase change materials in your thermal storage systems?

If so, could I ask what type and how well it has been working out?

I know certain salts have been used by some folks.

A friend of mine who is a chemist is looking into possibilities. The ultimate ideal would be a system that could capture heat during the summer using solar collectors, and store so much of it in so compact a space, that you could heat your house all winter on stored heat. I think it will be a long time until we have that.

Of course, there are these solar-collecting devices called "trees" that we can use to store solar energy for winter use

No personal experience with using phase change materials, but if anyone has resources on this, I would also be interested in seeing what's been done.

Joe

 

[Nofossil]

I looked long and hard at using paraffin. There are different formulations that melt at different temperatures, and the energy density is pretty good. Also, none of the problems with deterioration that some of the salts have. In the end, though, it's just a lot more expensive than water. You'd also need to disperse your hx tubing throughout the tank volume, since convection wouldn't work as well.

 

[LSaupe]

Thanks for the replies. The paraffins you were looking at, were these the type enclosed in small spheres or were you using it direct (as a solid volume)? Some of the newer sphere designs have a metal matrix inside to help dispurse the heat as well. Seems like the spheres would still work fairly well if decent circulation was imposed. I have seen this work quite well with cooling balls (spheres with water that turn to ice). This was a system that used cheaper night electricity to freeze the balls then use these balls to provide air conditioning (through chilled water) during the day.

I am looking at adding a thermal storage hot water system but am real tight on space. Would like at leats a 500 gallon thermal capacity.

If someone can come up with a compact (reasonably priced) system that is easy to use at hot water storage I'm sure it would be of great benefit to everyone (especially with the solar application mentioned above).

Larry S.

 

[Burn-1]

I found this one from a Slovakian manufacturer but it's pretty expensive. According to the price list, it's $3,696 Euros for a 500 liter tank which only holds 20 kwh of energy. According to the manual the tank holds about 430 liters of water and 20 kg of wax. Maybe OK for European sized dwellings or DHW but that's a lot to pay for 113 gallons of storage.

 

[LSaupe]

I like it, but yep could be better in the capacity department for the $$$ rendered. Do like the constant temp characteristics and space savings of PCM's though. I imagine it will be the way of the future once they get things dialed in a bit better and bring the costs down.

Thanks for posting the link.

Larry S.