Coca-Cola is going to distribute 16 replacement caps for plastic Coke bottles which will serve a variety of after uses, including water guns, paint brushes, condiment dispensers, sprayers and misters...
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Bottles, whether plastic or glass, have been used for years in solar energy collection:
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A cap that could pressurize the fluid inside and a simple bottle to bottle plumbing system would help with some ideas I've had for a number of years.
We can design our packaging for secondary uses. Pizza boxes can become solar cookers, take-out cartons can become "haybox" cookers or solar cookers themselves.
And then, of course, we can design our distribution systems so that we need little or no packaging at all.
Coca Cola knows that bottle caps are not the answer. It introduced the PlantBottle in 2009, made partially from plants and 100% recyclable, and is working with Ford and Heinz to share the technology with a goal of making all Coke's PET bottles from plant derivatives by 2020. They are also experimenting with a simple way to recycle their bottles into 3D printer filament.
Bottle caps seem to be a center of design interest these days. Brazil's Clever Caps (http://www.cleverpack.com.br/...) are bottle caps that can fit Lego blocks. Another take on the bottle cap as interlocking toy block comes from China: http://exhibition.ifdesign.de/...
The Petamato (http://www.buypetomato.com) is a bottle cap that turns a plastic bottle into a hydroponic garden, $14.99 for the full kit and caboodle.
The Vittel Refresh Cap is a mechanical timer cap that counts down each hour and pops up a small red flag when it’s time to drink more water. The timer resets every time the cap is twisted back onto the bottle.
Both the Vittel Refresh cap and Coke's set of 2nd Lives caps come out of advertising agencies.