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Bicycle Bottle System Condenses Humidity From Air Into Drinkable Water
Diggester writes The weight of water limits how much can be brought on a long bike ride. There isn't always an option to stop and fill up from a clean stream or drinking fountain, but water could be obtained from a different source: the air. Austrian industrial design student Kristof Retezár has created Fontus: a prototype of a water bottle system that condenses humid air into clean, drinkable water. His design made him a finalist for the 2014 James Dyson Award.
Apparently the industrial design curriculum doesn't cover thermodynamics. Condensing water at room temperature requires shedding about 680 watt-hours of energy per liter, and thermoelectric coolers tend to burn off more than twice the energy they pump (depends on a few variables, but practical devices in practical situations usually fall in that ballpark). You'd need somewhere near a constant half-kilowatt to provide for one person's normal water consumption. Much more if they're exercising or in a hot environment.
Bugrit! Millenium hand and shrimp!
1 drop per minute is at 20C and 50% RH = 3ml/hr (0.05ml/drop). At that temp/RH, there is 0.01 kg moisture per kg of air. But in hot, humid weather (say 35C and 90% RH), there is 4x as much moisture in the air. More importantly, at 20/50% the dew point is 9C, or a delta T of 11C that the (horribly inefficient) peltier cooler must keep just to condense moisture. At 35C, and 90% RH, the dew point is 33C, requiring only a 2C delta T across the cooler, allowing more of the power to be used for the latent heat of condensation.
Is it just my observation, or are there way too many stupid people in the world?
The article gives a rate of 1 drop per minute when it "starts to work". This means a standard 1/2 liter bottle would take over 2.5 hours to fill in 68 degree weather at 50% humidity, which doesn't seem that practical.
In idea conditions, it still take an hour to fill that bottle. 0.5 L is not a lot in 100% humidity, and whatever hot temperature the maker considers ideal.
Yeah well I'm a 400km a week cyclist and I do Ironman. A 5K bike is NOT just about weight. Aero, stiffness, handling, quality of carbon, ride..... they all factor in and THAT means time savings or watt savings.
Anyone that thinks 5K for a bike is just about weight is a cafe racer. Yeah sure, maybe a 2K sportive is about 10 minutes slower than a S-Works Tarmac over 90 kms but that is huge difference when your ass is on the saddle. The sportive is also wasting watts on frame twist, the S-Works puts every scrap to the wheel. Or how about alloy verses carbon aero wheels? I dont wear 45mm carbon wheels for weight, it's all about aero gains. Or how about a set of 3T aeromax handlebars? Dont have those for weight, those save 20watts at my typical speed. Oh and they remove road hum too.
And the real reason why I ride expensive bikes? After 200 kms I'm feeling okay enough to turn around and do it again. Cheaper bikes leave you a rattled sore mess.