Molecular Solar Thermal Energy Storage (MOST), Game Changer?

Recent developments in the MOST technology is looking very promising; Article. Essentially scientists in Sweden have developed a molecule that can take in energy from the sun in a solar collector setup and store it in the form of an energy rise isomer for very long periods without special handling (currently 18 years). When the liquid containing the stored heat at 68°F is passed over over the filter/catalyst the liquid warms to 150°F. They expect to be able to improve the upper temps to at least 230°F (hot enough to turn water to steam).

The scientists are designing a comprehensive system and expect commercial application within 10 years.

Wow James, thanks for the great post.  I haven't run across this work before....how great is this?  I hope it pans out well and doesn't have any unintended issues.  I'll be reading more deeply on this.

In BTU or Joules I would like to know how much actual heat/energy it hold per gallon/liter.
With that I can actually compare it better, when it comes to space/water heating for home use.

I like that we don't need insulation for the thermal storage tank, unlike a regular hot water tank.
Will I need 300gallon of this liquid to heat up 10gallon of water for my shower or will I only need 1gallon.
18year until self-discharge sounds like a military application vs home use.

I think this is mostly good for annualized solar storage near the arctic circle.
I am not sure they can beat stratified thermal storage, in therms of energy/volume.

I wish they would list a use case where it is better than water.

In this article; “Moth-Poulsen has calculated that the best variant of his fuel can store up to 250 watt-hours of energy per kilogram. Pound for pound, that's roughly twice the energy capacity of the Tesla Powerwall batteries that some homeowners and utilities now use to store electricity generated by solar panels.”

Water = 4.2kJ/kgC * 70C = 294kJ/kg=294kWs per kg = 294,000Ws per kg
Water = 294kWs * (1/3600hr/s) = 81.7WHr/kg aka 81.7WHr/l

It sure does beat water with a temperature delta of 70C.
With 250W/kg vs 81W/kg aka 3:1
Now I just wonder what lt's density or WHr/volume is?
I have a feeling that water is 300% as dense as it, so just about equal by volume.😇
Either way it sure beats water.

I like this compound, I wonder what the price will be.
And what happened if the energized and regular state is mixed
What happens if a mixture of both compounds is sent to the solar collector?
What happens if a mixture of both is sent to the burner/catalyst/discharger.
I ask all those because I would rather to just have 1 reservoir vs I full one and then an empty one.
But maybe they could put a separator in the one tank that divides them dynamically.

We could also store this compound above room temp insulated we could still store some energy in it, thermally in addition to it's chemical storage. Maybe we could stratify it to.

So how much would I need (Mass state avg)
Winter Heating needs = 800therms
Winter Heating needs = 800therms * 29.3kWH/therm
Winter Heating needs = 23,440kWH
Kg needed = 23,440kWH / 250WH/kg = 93,800Kg
Volume needed = ??? (If it was as dense as water 93,800l aka 25,000gallon)

Maybe I should think about this in terms of weekly or daily needs vs annualized solar storage.
Which would be 488.5kg/day or 3,400kg/wk
(If it was as dense as water 100gallon+ tank or 800gallon for a week storage)

Bengi, I can’t answer your questions rgdg mixing the activated & non-activated fluids. As it is individual molecules that are charged with energy from sunlight, energy they retain until said energy is expressed as increased temps when the fluid is passed through a catalyst filter. The molecule can then be returned to the solar collector to be recharged, over and over. They say the catalyst is showing to be durable, suffering only minor degradation that would eventually require replacement or some kind of recharging. one big breakthrough is the more recent version of the fluid was able to eliminate flammable toluene as the medium the molecules were carried in. That combined with the durable heat retaining molecule & catalyst  is why I suspect the scientists are so enthusiastic about possible commercial application as soon as 10 years. They say there are 15 teams working on this technology around the world, so I would think we will see more good news soon. Apparently the molecule takes only a small amount of the wavelength of sunlight into it as energy, primarily the blue and UV parts of the spectrum, so obvious expanding that would be a priority.

I foresee a vast array of applications if the application proves out and improves. The ability to turn sunlight into steam using solar collectors could drive turbines to create electricity at the same time it’s heating your floors. Excess heat could warm greenhouses during winter months. The fluid, once charged could be transported safely and could possibly drive steam engine vehicles if the energy/weight ratio improves enough. They say there isn’t anything about the manufacturing processes they see in creating these planned systems that is environmentally destructive. Honestly, if a 300 gallon tank in the back yard and solar collectors on the roof is part of the price I pay for reliable heat all winter and for many winters to come while eliminating fossil fuel use...here, take my money!

They list 250WH/kg but that is for the pure stuff. What happens when it it diluted with the new non-flammable solvent that they are using now? It will go down to 125WH/kg.

They only list weight which is good in terms of making sure that your walls/floor is strong enough to hold it up. But most people care more about looks/volume. Is this things as dense as lead and take up very little space or light like Styrofoam and will need two basement per floor.

Also how much of the sunlight is it capturing. 20% like solar electric panels or 70% for other solar hot water heater panels. It it is only 5% we might as well use regular solar panels to collect the sunlight (20%) at and then send it to a blue/UV light bulb with say a (90% efficiency) for a total efficiency of 18% (.20 X .90).