Troy Rhodes wrote:I purchased a BayGen radio b/c I liked the concept so much. THat's a radio where you wind a spring and that runs the radio for ~ 30 minutes. It was a big bulky box for essentially a tiny am/fm radio, just because of the spring. It cost over a hundred bucks, just because of the spring/engineering. Warnings all over the place to -NEVER- open the radio due to safety concerns about the spring.
Topher Belknap wrote:
Here is some of the math. Average humans can generate about 1/10 of a horsepower. For your pedaling to make coffee example, a pound of water heated from 50°F to 200°F requires 150 BTUs, 1/10 of a horsepower is 4.3 BTUs per minute. So, heating your coffee water (perfectly efficiently) would require 35 minutes of pedaling. 1/10 of a horsepower is about 75 watts, that is equivalent to about 1 foot² of solar panels (during sunny times), that is about $60 worth of panels (plus BOS, so maybe twice that). Since we get about 4 sun-hours per day in my climate, a human's eight hour day is the equivalent of 2 foot² of solar panels, or 1/50th of a gallon of gasoline (per day), or 0.6 kWh per day (10 cents worth for me).
Connor Macreno wrote:
You assume a COP of one, yes? How about spinning a heavy flywheel to even out output and gearing it to run a heat pump compressor? Shouldn't it be possible to cut the time to less than half your estimate? Maybe use one side to cool a cold pack to take with my lunch and the other side to heat my coffee, both with less time than many people devote to a morning exercise routine and no need for grid power.
Connor Macreno wrote:I'm now really thinking I need to build this.
Connor Macreno wrote:Any idea where I can buy a cheap compressor out scavenge one that would be suitable?