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Edit: I just found another german company using heat for cooling, this one is using zeolite: http://invensor.com/en/technology/zeolite.htm
So, assuming it is cheap and available, that's storage for solar power solved.
The easiest way to understand this is the formula for Carnot efficiency: 1-(Ambient temp/Heat temp) which is the maximum theoretical efficiency that can be extracted from a heat engine to do useful work (eg. produce electrical power)
So I don't know how fast this Zeolite releases heat, but let's say it does so gradually so that your working fluid only ever gets to 90 degrees C or 363K. The maximum Carnot efficiency on a 20 degree C (293K) day would be 1-(293/363) or around 19%. And that's the theoretical max - a practical engine would be much lower.
So if the Zeolite can release its heat fairly quickly at a much higher temp it could be useful for power generation, but basically it's more likely to be useful for releasing low level heat again when it's needed.
So, assuming it is cheap and available, that's storage for solar power solved.
Now we have yet another effect: The mass density of these zeolite balls is probably WAY below that of oil. Let's be generous and say it's a factor of 2. That means we would need 70 times the shipping volume of oil tankers to replace oil as our primary energy source. House tanks would need 70 times the volume. Car tanks would need 70 times the volume. Let's put it another way: For every liter of oil you use to transport them, you would need more than 70 liters of these transported JUST TO BREAK EVEN. I therefore heavily question whether this is useful even for the applications they claim. If anything they would have to be used very locally, not much more than the range we have today with isolated water pipers for transporting heat.
So yeah. These funny balls might be interesting for SOME applications, but they're far from being efficient enough for mass adoption.
Earlier quoted context omitted.
The article gives one example: you could charge them with waste heat at plants and factories, then transport them to homes and offices where (I suppose) they could be used for heating and hot water, at some later point in time. Sounds more efficient than teleheating via insulated pipes: http://en.wikipedia.org/wiki/District_heating
This is a great application. It could be particularly useful in the New England states. Manufacturing could store their waste heat in the zeolite, and resell it to homes and businesses who can use it to heat up during the winter. It could be a major disruption to utility companies.
So, assuming it is cheap and available, that's storage for solar power solved.
Water-Splitting using natural sunlight is a difficult problem and many research groups at top institutions are working on it. The best known group in this field is Prof. Daniel Nocera at MIT. His research is being commercialized by the company Sun Catalytix and there are plenty of YouTube videos of him speaking and explaining his research. There are other research groups as well. The vision for the future is a distributed electrical grid. Each home or building would have a reactor on top that would contain a water-splitting catalyst producing hydrogen and oxygen gas, which can be stored indefinitely under pressure and then released into a fuel-cell device that would recombine to form water (that can be placed into the reactor) and electricity (for consumption). This would be an efficient way to capture much more of the sun's energy than current photovoltaics and is an entirely closed cycle.
So, assuming it is cheap and available, that's storage for solar power solved.
Probably not. It's important to distinguish the storage of heat and power because the efficiency of converting heat into electrical power depends on how big the temperature difference between your heat source and ambient temperature is. The easiest way to understand this is the formula for Carnot efficiency: 1-(Ambient temp/Heat temp) which is the maximum theoretical efficiency that can be extracted from a heat engin…
Still, I prefer finding out that I am dreaming and being wildly optimistic, than to never bother dreaming or being wildly optimistic in the first place.
So, assuming it is cheap and available, that's storage for solar power solved.
The amount of energy you can store in this type of interaction is not very significant compared to other forms of solar storage. Batteries are one class of storage methods, but what's even better is to use solar energy to split water molecules and store it in molecular hydrogen and oxygen (H2 and O2). These can be recombined in a fuel cell to produce water (with no loss in molecules) and produce electricity. A much,…
Earlier quoted context omitted.
Not exactly because it doesn't change the design space of CSP, it just offers up a different heat storage mechanism. To put it differently, if heat storage was the only problem with CSP, and there is already a heat storage solution available (liquid salt) then Zeolite isn't solving a known 'problem'. You don't need 'indefinite' heat storage for CSP, you really only need a couple of days worth, and we have that alread…
Was thinking of it more as an urban/industrial thing. Makes sense if you have to do power storage with this technology to do a lot of it at the street level if you can, rather than on the power generation site, as it gives you multiple redundancy and you have to supply cities with water anyway. So when you have excess electrical power you dry pellets. When you want power you give them water vapour which then gives yo…
Short version of the science: The heat is released via an exothermic chemical reaction between the Zeolite and water. However, unlike the one-time-use chemical-reaction heating pads you can buy in a pharmacy, this reaction is reversible, so you can "recharge" the Zeolite by heating it and removing the water as it is released in order to force the reaction to reverse itself. The reaction goes something like this: Zeol…