Molten Salt Storage System

[ranya]

Hello! I was hoping that someone could please provide me with some information on molten salt storage systems. I have been doing some research and I need help in figuring out how to build one for personal home use. The house is in Michigan and is off the grid and we want to find a way to store the surplus solar energy we get from the summer and use it during the winter. If someone could please help out, that would be great!!

[russ]

Hello! I was hoping that someone could please provide me with some information on molten salt storage systems. I have been doing some research and I need help in figuring out how to build one for personal home use. The house is in Michigan and is off the grid and we want to find a way to store the surplus solar energy we get from the summer and use it during the winter. If someone could please help out, that would be great!!

No way possible to do what you describe today - maybe a hundred years on.

[Sunking]

Dream on my friend.

[J.P.M.]

Hello! I was hoping that someone could please provide me with some information on molten salt storage systems. I have been doing some research and I need help in figuring out how to build one for personal home use. The house is in Michigan and is off the grid and we want to find a way to store the surplus solar energy we get from the summer and use it during the winter. If someone could please help out, that would be great!!

Seasonal storage has been a quest as long as solar assisted building heating has been around. Think of a building with a 4 to 6 month thermal time constant. Pretty far out, but maybe not quite so far as molten salt.

[SunEagle]

The only working solar heat molten salt systems are very large commercial operations using mirrors to concentrate solar on a tank or "target" to generate very high temperatures. These facilities cost millions of dollars to build and maintain along with needing hundreds of acres of land for the installation. Even the best results has only been about 6 to 8 hours of "storage" heat so the technology is a long way from being economical.

The only practical solar heat system for a home are the ones that will heat water.

[J.P.M.]

The only working solar heat molten salt systems are very large commercial operations using mirrors to concentrate solar on a tank or "target" to generate very high temperatures. These facilities cost millions of dollars to build and maintain along with needing hundreds of acres of land for the installation. Even the best results has only been about 6 to 8 hours of "storage" heat so the technology is a long way from being economical.

The only practical solar heat system for a home are the ones that will heat water.

FWIW, depending on climate and design, I've seen and been in some nice homes partly or even mostly heated by solar energy using passive solar principles. The owners generally seem to think they're practical.

[SunEagle]

FWIW, depending on climate and design, I've seen and been in some nice homes partly or even mostly heated by solar energy using passive solar principles. The owners generally seem to think they're practical.

I agree. I have seen and "felt" the heat at night from a patio that heated the floor during the day and it stayed warm all night. Storing heat in some things works and is economical. Storing heat in Molten Salt is very very expensive and still has a lot of design before it is economical.

Spain built the first solar molten salt heat system a few years ago and have recently shut it down due to costs.

There is a very large system on the boarder of California and Nevada, South of Las Vegas just West of Rt 15. It is called the Ivanpah Solar Concentrating project and it is about 392MW in size. You can see it using Google Earth. This facility is massive yet has only "stored" heat for about 6 to 8 hours at best.

Still a lot to learn about storing heat and making it economical.

[albert436]

I agree. I have seen and "felt" the heat at night from a patio that heated the floor during the day and it stayed warm all night.

How does that work ? ? ?

[SunEagle]

How does that work ? ? ?

This patio had a glass window enclosure like a green house. The sun came through to land on a type of flat stone that had very good heat absorption properties. When the sun started to go down they closed a shade across the windows to keep the heat in. The stones stayed pretty warm until late at night which made it quite comfortable to walk on with bare feet or with just your socks on. The stones wouldn't be hot enough to heat the house but kept the enclosed patio nice and comfortable.

[Mike90250]

here's a great write up about solar heat storage:

http://www.builditsolar.com/Projects/SpaceHeating/SolarShed/solarshed.htm

(and a minor update - http://www.builditsolar.com/Projects...Space/Main.htm )

"I should mention that we live in SW Montana at 46 degrees north latitude. Winters are chilly -- 8000 degree-days and down to -30F once in a great while -- with typical mid-winter highs in the 30F's. But, a fair number of sunny days that are a pleasant indeed."

So if you have some sunny days, this is a more affordable system than molten salt or sodium.

There are some wax formulations that store heat - google Phase Change Heat Storage, but it's hard to pumo the solid wax to the heater section.

[J.P.M.]

I agree. I have seen and "felt" the heat at night from a patio that heated the floor during the day and it stayed warm all night. Storing heat in some things works and is economical. Storing heat in Molten Salt is very very expensive and still has a lot of design before it is economical.

Spain built the first solar molten salt heat system a few years ago and have recently shut it down due to costs.

There is a very large system on the boarder of California and Nevada, South of Las Vegas just West of Rt 15. It is called the Ivanpah Solar Concentrating project and it is about 392MW in size. You can see it using Google Earth. This facility is massive yet has only "stored" heat for about 6 to 8 hours at best.

Still a lot to learn about storing heat and making it economical.

Not to be argumentative, but the Solar 2 facility near Barstow, CA, while not a commercial venture, used a molten salt system in 1995 and ran for a few years. Technically it was more a research/make work project, but was a 10 mW facility and did feed production to the commercial grid. The power tower has been dismantled, the mirrors removed and the facility reconfigured, but it was something to see and more to the point feel the heat up close, about 300 yards or so from the receiver, when operating.

[SunEagle]

Not to be argumentative, but the Solar 2 facility near Barstow, CA, while not a commercial venture, used a molten salt system in 1995 and ran for a few years. Technically it was more a research/make work project, but was a 10 mW facility and did feed production to the commercial grid. The power tower has been dismantled, the mirrors removed and the facility reconfigured, but it was something to see and more to the point feel the heat up close, about 300 yards or so from the receiver, when operating.

I found that site on Google Earth as well. You can still see the equipment because the picture was taken before it was dismantled. It provided some pretty good data for research but as you indicated it was shut down.

Besides the Ivanpah 392 MW facility in CA. (which is now operational), I believe there is another very large Concentrating Solar plant in Nevada which is about 110MW in size. Both use the Molten Salt technology for heat storage.

I always hoped that this technology gets a breakthrough because "storage" is the key for most renewable generation.

[albert436]

Seems like a good point.

JPM have you been interested in this type of thing for so long that you made a special trip out to visit the site near LV, more than 15 years ago?

How does one find that on Google Earth?

[SunEagle]

Seems like a good point.

JPM have you been interested in this type of thing for so long that you made a special trip out to visit the site near LV, more than 15 years ago?

How does one find that on Google Earth?

I have subscribed to a Magazine called EnergyBiz and get daily emails listing news reports on everything dealing with power generation including renewable. If something interests me I look for more info on the web and usually with either a city or road name can find the place on Google Earth. The only bad thing is that Google Earth is not always up to date so when I find that a new Solar PV field has been recently built I sometimes only find picture of farm land from a year before the Solar project started. But you would be surprised on the number of huge solar arrays, wind generators and geothermal plants that are available to find.

[albert436]

That is quite interesting, that guy from Taiwan mentioned the National Stadium and Park and on GE neither were shown, the stadium was just a big empty lot.