I hope this topic is appropriate to the list.
Here in New Zealand we are comming to the end of a long (too dam
hot for my Irish blood) hot summer whith tempratures regularly in the
high 20s and often in the 30s (C that is) now that winter is on it's
way again I was thinking 'Would'nt it be nice if I could store some
of that excessive summer heat to warm my house in winter.' A few days
ago (in the absence of this forum) I remembered a heat pad that my
folks used to use to keep their hands warm while running sailing
races during the winter. The pad was a sealed plastic bag containing
a substance which was either liquid/charged or solid/discharged.
When it was discharged the pad was placed in a pot of boiling water
until the white solid became completely liquid (as I remember the
liquid was light brown like oil). When removed from the water the pad
would cool to room temprature and the contents would remain liquid,
the pad could be stored like this for weeks (indefinitly??).
When heat was required from the pad, a plastic element inside the bag
was bent, this triggered a reaction in the liquid which would revert
to it's solid state releasing heat over a period of time (about an
hour I think).
This pad was storing heat without a need for insulation, the physics
seems ideal for packing away summer heat for winter use, all that is
needed is space like the roughly 100m cubed under the floors of my
house.
Questions:
Do you know what the substance in the bag is?
If so:
What volume is required to produce a kWhr of heat?
What temprature is required to 'charge' the substance?
Well there it is, my first submission to KeelyNet
BFN
Pete