3 ms·

> And consumers can cheaply add some phase change materials for a boost in thermal banking (like really salty water bottles). What does this do?

_Microft 3y ago
Phase change materials are a way to store lots of energy at a given temperature. You might have noticed how much time it takes to freeze something - that's because lots of energy need to be extracted from liquid water to turn it to ice. And that without even changing temperature - it all happens at 0°C. With other materials, you can have a similiar effect at other temperatures. This can be used to create a system that keeps a certain temperature even if energy flows into or out of it (until the phase transition is complete). Read more here: https://en.wikipedia.org/wiki/Phase-change_material https://en.wikipedia.org/wiki/Phase-change_material
- bombcar 3y ago
  You can do it with hot water too - heat your water to near boiling, and merge it with cold to make the desired temperature. The heater won’t turn on until the temperature drops below a threshold. Using this you can avoid hearing water during high demand times.
  - _Microft 3y ago
    A phase transition can store lots of energy without the inconvenience of changing temperature. Melting water ice into liquid water at 0°C takes approximately as much energy as heating the same amount of water from 0°C (assuming that it is already/still liquid) to 80°C. With a material that has a transition temperature of e.g. 21°C, a room could be kept at a very pleasant temperature even when energy is flowing into or out of it.
milesvp 3y ago
fun story. I know a guy who designed a high precision refrigerator for storing vaccines. These fridges need to be able to maintain temperature to within some relatively small margin to avoid destroying the vaccines, and they needed to be able to withstand extended periods of no power since they would be stationed in places with questionable infrastructure. The main solution was to use a large water reservoir, it would "store most of the cool" while the power was out, also helped a lot with keeping the temperature stable when there was power.

_Microft 3y ago

Phase change materials are a way to store lots of energy at a given temperature. You might have noticed how much time it takes to freeze something - that's because lots of energy need to be extracted from liquid water to turn it to ice. And that without even changing temperature - it all happens at 0°C. With other materials, you can have a similiar effect at other temperatures. This can be used to create a system that keeps a certain temperature even if energy flows into or out of it (until the phase transition is complete). Read more here: https://en.wikipedia.org/wiki/Phase-change_material https://en.wikipedia.org/wiki/Phase-change_material

bombcar 3y ago
You can do it with hot water too - heat your water to near boiling, and merge it with cold to make the desired temperature. The heater won’t turn on until the temperature drops below a threshold. Using this you can avoid hearing water during high demand times.
- _Microft 3y ago
  A phase transition can store lots of energy without the inconvenience of changing temperature. Melting water ice into liquid water at 0°C takes approximately as much energy as heating the same amount of water from 0°C (assuming that it is already/still liquid) to 80°C. With a material that has a transition temperature of e.g. 21°C, a room could be kept at a very pleasant temperature even when energy is flowing into or out of it.

milesvp 3y ago

fun story. I know a guy who designed a high precision refrigerator for storing vaccines. These fridges need to be able to maintain temperature to within some relatively small margin to avoid destroying the vaccines, and they needed to be able to withstand extended periods of no power since they would be stationed in places with questionable infrastructure. The main solution was to use a large water reservoir, it would "store most of the cool" while the power was out, also helped a lot with keeping the temperature stable when there was power.