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A 38 page powerpoint presentation. Very illuminating. Who knew such things as: Liquid hydrogen leaks can be ignited by the static spark set off by the leak it

A 38 page powerpoint presentation. Very illuminating. Who knew such things as: Liquid hydrogen leaks can be ignited by the static spark set off by the leak itself? Hydrogen flames are not visible (see slide 16: hydrogen refinery would look same when on fire as when not. Compressed H2 gas or Liq H2 have only about 15% or 30% of the energy-per-gallon as gasoline. And on and on... Sure casts doubt on feasibility of H2 as a medium for energy storage.

TriinT 17y ago
Indeed. I found the following amusing: "There is actually more hydrogen in a liter of gasoline (116 grams) than there is in a liter of pure liquid hydrogen (71 grams)!" But the coolest of all is that hydrogen flames are invisible! Hydrogen flames are so energetic that they emit UV radiation! I remember when I was in grade school and tried electrolysis at home. I managed to collect some hydrogen in a test tube, and I ignited it with a match. I heard a loud bang, but no flame. Sound, but no light. That was fascinating.
nazgulnarsil 17y ago
so what youre telling me is that setting someone on fire with hydrogen is the perfect crime.
- endtwist 17y ago
  Or methanol (under the right circumstances): "Pure alcohols burn with a nearly invisible flame in daylight." (http://www.energyquest.ca.gov/transportation/alcohols.html http://www.energyquest.ca.gov/transportation/alcohols.html) Which was done in (yeah, I know) an episode of CSI:Miami: http://csimiami.wetpaint.com/page/207:Grand+Prix http://csimiami.wetpaint.com/page/207:Grand+Prix Though, of course, hydrogen is far more exciting.
jws 17y ago
hydrogen refinery would look same when on fire as when not. - except for the heat wave distortion, plumes of smoke from burning paint, drooping steel gangways, showers of electrical sparks from the shorting electrical system, and workers leaping from the upper levels.
- potatolicious 17y ago
  And if the fuel in a hydrogen car decided to burn, everyone in its vicinity will find out in a real hurry - a fire that looks different is still a fire. Though his point is valid - hydrogen will burn extremely quickly, we used to do these as demonstrations in school. Where a pool of gasoline will burn over a period of time, a tank full of hydrogen will burn almost instantaneously to disastrous effect - forget about rescue, the only sort of "rescue" will be body retrieval of whatever is left.
  - likpok 17y ago
    However, hydrogen will not pool like gasoline. If it doesn't ignite, it will just fly off into space. This mitigates some of the risk (i.e. if there is an accident, a fuel leak will either kill you quickly, or it won't)

TriinT 17y ago

Indeed. I found the following amusing: "There is actually more hydrogen in a liter of gasoline (116 grams) than there is in a liter of pure liquid hydrogen (71 grams)!" But the coolest of all is that hydrogen flames are invisible! Hydrogen flames are so energetic that they emit UV radiation! I remember when I was in grade school and tried electrolysis at home. I managed to collect some hydrogen in a test tube, and I ignited it with a match. I heard a loud bang, but no flame. Sound, but no light. That was fascinating.

nazgulnarsil 17y ago

so what youre telling me is that setting someone on fire with hydrogen is the perfect crime.

endtwist 17y ago
Or methanol (under the right circumstances): "Pure alcohols burn with a nearly invisible flame in daylight." (http://www.energyquest.ca.gov/transportation/alcohols.html http://www.energyquest.ca.gov/transportation/alcohols.html) Which was done in (yeah, I know) an episode of CSI:Miami: http://csimiami.wetpaint.com/page/207:Grand+Prix http://csimiami.wetpaint.com/page/207:Grand+Prix Though, of course, hydrogen is far more exciting.

jws 17y ago

hydrogen refinery would look same when on fire as when not. - except for the heat wave distortion, plumes of smoke from burning paint, drooping steel gangways, showers of electrical sparks from the shorting electrical system, and workers leaping from the upper levels.

potatolicious 17y ago
And if the fuel in a hydrogen car decided to burn, everyone in its vicinity will find out in a real hurry - a fire that looks different is still a fire. Though his point is valid - hydrogen will burn extremely quickly, we used to do these as demonstrations in school. Where a pool of gasoline will burn over a period of time, a tank full of hydrogen will burn almost instantaneously to disastrous effect - forget about rescue, the only sort of "rescue" will be body retrieval of whatever is left.
- likpok 17y ago
  However, hydrogen will not pool like gasoline. If it doesn't ignite, it will just fly off into space. This mitigates some of the risk (i.e. if there is an accident, a fuel leak will either kill you quickly, or it won't)