18 Jul
2013
18 Jul
'13
11:52 a.m.
On 7/18/2013 7:22 AM, Simon Plouffe wrote:
Another example : simple mirrors, why can't we buy , find a simple device to produce 2000 watts when there is a lot of sun for cheap ??, This does WORK, in africa they have a lot of those sun-ovens, it uses the sun to cook something : so there is a way to get 1000-2000 watts with a device that cost 100 $, what is the problem, can't we just multiply to get 1 gigawatt ?
You're ignoring the entropy. A watt of electrical power is very low entropy and hence much more useful and valuable than a watt of heat at 100C. That's why it's cheap and easy to get heat from sunlight, but hard to get electricity. Brent Meeker