h a l f b a k e r yBaker Street Irregulars
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
|
I'd like to say "good idea" but my old physics lessons are saying "Can't see it making enough heat". |
|
|
<frowning> I think it takes about 70KJ of heat energy to change temperature of a mug water from 30C to 100C. PV cells produce a couple of watts each. I'm not going to wrack my brains for conversions and actually fitting these facts together into an argument..I'm just going to look sceptical </frowning> |
|
|
Depending on the resident climate and time of year, I'll take the solar cooling version please. |
|
|
Maybe if you hook up the coffee in the cup with tubes to a solar "water" heater on the roof? |
|
|
[unabubba] Isn't spec heat cap...4190 J/ kg.K? Anyway....point still same in my opinion, to generate the electrical power to heat the water (through an inefficient heating element) there will have to be a much larger surface area of PV cells than you can fit on a mug. |
|
|
I'm with Jinbish on this one, but it's Friday afternoon and I can't be bothered to do the maths. </frowning and scowling>. |
|
|
Why bother with the conversion at all? Just get a glass coffee mug. |
|
|
But remember, the coffee is already hot when put in the mug. All this device does is just keep it warm for ages. so that you can leave the coffee for a couple of hours and it will be still as hot and fresh
(well not really fresh) as it was when you first poured. |
|
|
your mistake [amazing] was to say "heat your coffee" - if you had said *keep* your coffee hot, we would not have got into this maze. only problem is: the sun rarely reaches my little office. |
|
|
There we go, i changed it from to keep at desired
temperature. I think it's better, think...... |
|
|
UnaBubba's sight is failing him in his old age, methinks... |
|
|
My coffee never has a chance to get cold. |
|
|
Hmm, the most efficient solar absorbtion transducer would be... Why not just paint it black? |
|
| |