Hybrid Car – More Fun with Less Gas

Re: Deployable Doubt Dispellers

register ::  Login Password  :: Lost Password?
Posted by nicksanspam on February 24, 2006, 11:19 am
 


But smaller solar houses are harder to build, since heat loss increases with
exterior surface, ie the square of the edge length, but the volume available
for heat storage goes up with the cube. An 8' D-cube is mundane engineering.
A 4' D-cube would be a tour-de-force. A 2' version would be very difficult.
A 1' version would be almost impossible, even with evacuated silica gel
insulation encased in foil, at US R40 per inch.

We might have a smallest D-cube contest :-)

Nick


Posted by RicodJour on February 24, 2006, 2:47 pm
 

nicksanspam@ece.villanova.edu wrote:

That's all fine and dandy, but are you trying to convince people or
start a new hobby?  If it's supposed to be a house, people have to be
able to walk inside of it.  Looking at a thermometer through a window
won't convince someone as much as personally experiencing that
temperature.

The easiest thing to do is to build a house that's the footprint of a
roll-off dumpster, so it can be dropped in place and picked up and
moved.

R


Posted by nicksanspam on February 24, 2006, 3:40 pm
 

It needn't be a house, but a door sounds good for Ultimate Disbelievers.

Nick


Posted by RicodJour on February 24, 2006, 3:47 pm
 nicksanspam@ece.villanova.edu wrote:

You need to expand your thinking.  Stop thinking outside the box.
Inside is where it's at.

R


Posted by nicksanspam on February 24, 2006, 7:50 pm
 

We have 1) engineers and physicists who consider this an obvious and trivial
accomplishment and require no physical proof, 2) doubters, eg architects,
who are scientifically literate but have been confused by conventional wisdom
and SBIC guidelines claiming that houses can only be 60% solar-heated outside
of the southwest, and 3) ignorant arrogant actors like m ransley, who may
always imagine hoaxes and secret energy sources that keep the cubes warm.

The first and third groups can't be helped, but we might help the second :-)

"... 84 ft^2 of tank surface with 5x84 = 420 Btu/h-F of slow-moving
airfilm conductance could supply 840 Btu/h at 70 + 840/420 = 72 F.
Keeping the cube 70 F for 8 hours and 50 F for 16 hours on a cloudy day
takes (8h(70-30)+16(50-30))21 = 13440 Btu, so the tank might store heat
for 2x6x6x62.33(115-72)/13440 = 14 30 F cloudy days in a row.

Were m ransley less ignorant, he might have corrected the calc above:

"... 84 ft^2 of tank surface with 2x84 = 168 Btu/h-F of slow-moving
airfilm conductance could supply 840 Btu/h at 70 + 840/168 = 75 F.
Keeping the cube 70 F for 8 hours and 50 F for 16 hours on a cloudy day
takes (8h(70-30)+16(50-30))21 = 13440 Btu, so the tank might store heat
for 2x6x6x62.33(115-75)/13440 = 13 30 F cloudy days in a row.

Nick


This Thread
Bookmark this thread:
 
 
 
 
 
 
  •  
  • Subject
  • Author
  • Date
please rate this thread