Methanol Fluid

[Really?]

Has anyone survived using Methanol for Solar Thermal Panels fluid?

[neweclipse]

Methanol is a corrosive solvent.

[J.P.M.]

What's the point ?

Methanol is poisonous. That alone would remove it from consideration as a heat transfer fluid for most any solar application.

Besides, other than a low freezing point, the rest of the thermophysical transport properties of methanol with the exception of viscosity are such that it's not as good a heat transfer fluid as water, or water/prop. glycol mixtures if freeze protection is required.

Also, while methanol is mostly compatible with most metals used in solar thermal collectors, it may not get on well with a lot of gasketing/sealing materials.

[LucMan]

Methanol mixtures have been recommended for use in Geothermal applications, but is outlawed for use in certain states because of it's toxicity.
There are better alternatives IE propylene glycol for solar systems so why consider it?

[Mike90250]

I've seen acetone used as repair fluid in evacuated glass tube panels.

[Sunking]

Extremely dangerous, toxic, and corrosive.

[J.P.M.]

Extremely dangerous, toxic, and corrosive.

But great for breaking soap films and bubbles in hot tubs.

[cabindave]

Many on this forum use methanol regularly. You just may not know it. It is a standard ingredient in window washer fluid. In the northern climates, a very high percentage is often methanol.

I use it in a geothermal setup. I looked up its half life in earth and groundwater before using it. Where it would not use it is in an application where it is getting close to drinking water. A coil of methanol inside a water heater hooked to your home drinking system seems a bit odd to me. In a floor heat/non-potable situation it wouldn't be as much of an issue.

[Sunking]

Many on this forum use methanol regularly. You just may not know it. It is a standard ingredient in window washer fluid. In the northern climates, a very high percentage is often methanol.

True and the reason methanol is used instead of ethanol is alcoholics would drink it. Drunks know it would kill them if they drank it.

[J.P.M.]

True and the reason methanol is used instead of ethanol is alcoholics would drink it. Drunks know it would kill them if they drank it.

I've always said there's nothing worse than hoards of drunks attacking your heat pump. I hate it when that happens.

But seriously, aside from the greater pumping costs due to viscosities, and maybe a bit of additional fluid monitoring, there are other fluids that are probably as good or better working fluids for ground source heat pumps than methanol, including those applications in northern or freezing climates. The toxicity issue is real even if ignored in the past and carried into the present.

When I was a kid, used PCB laden transformer oil was sprayed on dirt roads in vacation/resort areas for dust control. We'd follow the spray trucks in bare feet and slide around on/in the slippery mud, then go jump in the lake and watch the water sheen. Good memories don't necessarily make it a good idea.

It seems that methanol is still used in smurf piss, but I' don't know how that's done or allowed w/all the toxicity surrounding methanol.

[bcroe]

When I was a kid, used PCB laden transformer oil was sprayed on dirt roads in vacation/resort areas for dust control. We'd follow the spray trucks in bare feet and slide around on/in the slippery mud, then go jump in the lake and watch the water sheen. Good memories don't necessarily make it a good idea.

I have a friend who collected the stuff, mixed it with diesel fuel, and used it to run his truck. I don't know if what
came out the exhaust was less toxic than its origins. Bruce Roe

[SunEagle]

I have a friend who collected the stuff, mixed it with diesel fuel, and used it to run his truck. I don't know if what
came out the exhaust was less toxic than its origins. Bruce Roe

Sounds almost as bad as barn yard fuel.

[Sunking]

I have a friend who collected the stuff, mixed it with diesel fuel, and used it to run his truck. I don't know if what
came out the exhaust was less toxic than its origins. Bruce Roe

Actually that is a common practice for diesel engines in cold weather. You can use 10% alcohol or gasoline to keep the diesel fuel from forming gel when cold. I use to make my own biodiesel years ago. Jet A Fuel has methanol in it to keep it flowing in high altitudes of -60 degrees F.

[mark in Portugal]

Methanol is far less poisonous that glycol, and it evaporates quickly if spilled. As far as nasty solvents and chemicals we use daily, it's quite benign. Just don't drink it.
Corrosive properties are still a problem of course; why would you want to use it? Is there some advantage?