Another point with regards to this kind of technology - any dust in the air will end up in the water. If the dust isn't sanitary or is otherwise polluted with nasties, it's not going to make safe drinking water, irrespective of the thermodynamic concerns.
If we disregards thermodynamics and dive into the engineering part of the bottle, things become very difficult indeed with amongst others the air polluting the water. In their pdf they claim that an airfilter will be installed "temptatively" (they probably mean 'tentatively', but that's less of the point). Installing an air filter was needed to be added to the bottle, because early on when most people didn't even mention thermodynamics yet, most were voicing concerns about 1) pathogens and dust from the air, and 2) about drinking the equivalent of distilled water (for some weird reason people thought water was the only source of minerals for the human body and that drinking distilled water would be a huge risk).
Pathogens/airfilter
- Building the system with an airfilter that handles this at this size is a huge, likely insurmountable engineering challenge. They probably think dehumidifiers have air filters, so this should be able to have them too without any issues, since they have a dehumidifier right? Wrong, the problem here is that dehumidifiers are
only concerned with filtering the air that
comes out of the dehumidifier and don't care how dirty the water is that is drained to a container. That is fairly straight forward because you only need to have the filter on the exhaust end of the airflow.
- The Fontus bottle is concerned about filtering the air that comes into the bottle, but ALSO on the exhaust end, since pathogens can come in from any side to contaminate the surface of the Peltier. This means they need to cocoon the entire cooling side of the Peltier around a HEPA (or HEPA like) filter. Furthermore, the entire cold side of the Peltier needs to be hermetically sealed away from the hot side to avoid air form the 'dirty' hot side from coming into contact with the air on the clean and cold side (apart from the fact that you want to keep hot air away from the cold side anyway) and if there is a direction in the airflow of the cold side at all, both intake and outlet have to be going through a HEPA-like filter.
This causes 2 engineering challenges:
1) How do you install an engine and fan strong enough to pull air through a HEPA filter to ensure you can extract enough water to condense, given that you can only condense a small portion of water at a time before you need to pull fresh air over the Peltier again. Anything with a HEPA filter usually makes a lot of noise, why?: because powerful fans/engine is needed to push/pull the air through the micro-filter cavities. Where is the room on top of that redesigned bottle to install a powerful fan to pull the air through the condensing part? The fan on top of the Fontus unit is clearly meant to cool the heatsink not for pulling any air through a filter on the bottom part and we already established that that top fan can not support the airflow of the bottom/cold part of the Peltier since it had to be separated anyway from the cold part.
2) How do you keep the HEPA cocoon around the Peltier dry? Water on these filters are not very good for them, but we just established that the entire bottom part of the Peltier needed to be surrounded by the filter to avoid contaminants to come in. But that means you are putting dripping water from the cool Peltier side, awfully close to the filter, since the bottle diameter is only about 12cm, so there isn't very much room to play around with especially if you need to install as large a Peltier as possible to generate any kind of water at all. In dehumidifiers this problem again is less of an issue since dehumidifiers are larger, where you can build an air channel away from the Peltier first (with some bends) and only then then push the air through the filter. We already established before that manufacturers don't want you moving a dehumidifier around when the water container is full. Furthermore, dehumidifiers have more room to separate the watercontainer further away from the filters as well as the Peltier from the Filters.
So basically, adding a microbial level filter seems to be a no-go for them and I wonder how they will address the concerns of people about bacteria like legionella etc after they announce that they cannot install an air filter after all and hide behind the 'temptative' label of the air filter aspect of the redesigned unit.
Mineralization
Something very funny is going on with the whole mineralization tablets. Back when Fontus first started many people on social media were commenting on how cool the bottle was but that they were concerned about drinking what seemed like distilled water (or the equivalent of it). For arguments sake lets assume that the water would indeed have been devoid of any minerals.
Fontus after a while responded by saying that they would make the bottle have a bottom compartment that contains tablets to re-mineralize the water, all to appease the mass of comments about lack of minerals and that is the version they released for IGG (see bottom of image of the original IGG Airo bottle).
- The concerns about the lack of minerals were absurd of course. The bottle was meant to provide water during hikes or or short trips. First off, a large portion of minerals are or can be readily provided by food. Dehydration is a much larger risk than any minerals deficiency you might have in the period you are dying of thirst. Anyone willing and prepared enough to bring a 250USD bottle on a hike, probably has power bars and enough food for the trip with them, while relying on that magical 0.8L/hour water from the Fontus for hydration. But since these art students lack any hint of scientific understanding, they simply through, hey, let's add a chamber to shut up the critics, not knowing it was a solution to a non-existent problem. Mineral deficiency is something that would only occur over weeks or likely months under a normal diet, if at all.
- In the latest iteration Fontus kept the re-mineralization need alive, by saying that you can add your tablets after pouring water out the Airo. The reason they now claim you have to add the minerals yourself afterwards, is because the bottom in the new redesigned bottle is reserved for the intelligent power converter or whatever they call it. So they no longer could add the 'chamber for minerals' unless they would make the volume for water even less.
- And here is the kicker: they now show the Fontus in a kitchen setting, plugged in and generating water of the mains power and then adding a tablet afterwards. All the while it is faster and cheaper to get water out of the tap and yes: that tap water already has minerals so you don't need to add any anymore (although we already said it was not needed anyway).
So they created a bottle that included a solution for a non-existent problem of mineral deficiency that now is scrapped and replaced by adding your own tablets, while you are at home where you have all the mineralised water and food you can imagine to avoid getting a mineral deficiency in the first place.
These guys are so clueless that it all would be funny if only they weren't scamming 1600 people out of their hard earned money.
