<story><title>New ‘mirror’ fabric can cool wearers by nearly 5°C</title><url>https://www.sciencemag.org/news/2021/07/new-mirror-fabric-can-cool-wearers-nearly-5-c</url></story><parent_chain><item><author>teruakohatu</author><text>They appear to just circulate air around the body, which makes sweat evaporate cooling the body. If they were actual air conditioners they would be indeed moving heat from the body into the surrounding air.&lt;p&gt;Edit: to be clear I am not suggesting heat&amp;#x2F;energy disappears. In this case they are cooling the air and the body using evaporation. The system appears to suck in hot air on one side   and ejects cooler humid air on the other. More or less human swamp coolers.&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.m.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Evaporative_cooler#Physical_principles&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.m.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Evaporative_cooler#Physical_...&lt;/a&gt;</text></item><item><author>SapporoChris</author><text>I have seen these and pondered if it is rude to wear them. While it is actively cooling your body, you are aggressively blowing your heat to those around you. In a crowded subway train I would not want to be next to someone wearing this. However, perhaps I overestimate their effects.</text></item><item><author>rwmj</author><text>In Japan they have these portable AC jackets.  I believe they are mainly used by people working on building sites where it gets very hot in summer.  While these are actively cooled rather than passively (as in the article), they seem like a better idea than air conditioning whole rooms.&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;wonderfulengineering.com&amp;#x2F;japanese-invent-a-jacket-with-air-conditioner&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;wonderfulengineering.com&amp;#x2F;japanese-invent-a-jacket-wi...&lt;/a&gt;
&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.dailymail.co.uk&amp;#x2F;sciencetech&amp;#x2F;article-2016513&amp;#x2F;Japanese-company-creates-air-conditioned-jacket-Kuchofukus-cool-look.html&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.dailymail.co.uk&amp;#x2F;sciencetech&amp;#x2F;article-2016513&amp;#x2F;Japa...&lt;/a&gt;&lt;p&gt;(Sorry can&amp;#x27;t find any good links - the jackets aren&amp;#x27;t a fad and seem to be popular with builders)&lt;p&gt;Edit: The company website (Japanese) &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;kuchoufuku.com&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;kuchoufuku.com&lt;/a&gt;</text></item></parent_chain><comment><author>noctune</author><text>It&amp;#x27;s the same dilemma though. Now you are raising the humidity around you, making other peoples&amp;#x27; sweat less effective at cooling them.&lt;p&gt;Although lowering humidity can be more easily done with just ventilation.</text></comment>
<story><title>New ‘mirror’ fabric can cool wearers by nearly 5°C</title><url>https://www.sciencemag.org/news/2021/07/new-mirror-fabric-can-cool-wearers-nearly-5-c</url></story><parent_chain><item><author>teruakohatu</author><text>They appear to just circulate air around the body, which makes sweat evaporate cooling the body. If they were actual air conditioners they would be indeed moving heat from the body into the surrounding air.&lt;p&gt;Edit: to be clear I am not suggesting heat&amp;#x2F;energy disappears. In this case they are cooling the air and the body using evaporation. The system appears to suck in hot air on one side   and ejects cooler humid air on the other. More or less human swamp coolers.&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.m.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Evaporative_cooler#Physical_principles&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.m.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Evaporative_cooler#Physical_...&lt;/a&gt;</text></item><item><author>SapporoChris</author><text>I have seen these and pondered if it is rude to wear them. While it is actively cooling your body, you are aggressively blowing your heat to those around you. In a crowded subway train I would not want to be next to someone wearing this. However, perhaps I overestimate their effects.</text></item><item><author>rwmj</author><text>In Japan they have these portable AC jackets.  I believe they are mainly used by people working on building sites where it gets very hot in summer.  While these are actively cooled rather than passively (as in the article), they seem like a better idea than air conditioning whole rooms.&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;wonderfulengineering.com&amp;#x2F;japanese-invent-a-jacket-with-air-conditioner&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;wonderfulengineering.com&amp;#x2F;japanese-invent-a-jacket-wi...&lt;/a&gt;
&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.dailymail.co.uk&amp;#x2F;sciencetech&amp;#x2F;article-2016513&amp;#x2F;Japanese-company-creates-air-conditioned-jacket-Kuchofukus-cool-look.html&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.dailymail.co.uk&amp;#x2F;sciencetech&amp;#x2F;article-2016513&amp;#x2F;Japa...&lt;/a&gt;&lt;p&gt;(Sorry can&amp;#x27;t find any good links - the jackets aren&amp;#x27;t a fad and seem to be popular with builders)&lt;p&gt;Edit: The company website (Japanese) &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;kuchoufuku.com&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;kuchoufuku.com&lt;/a&gt;</text></item></parent_chain><comment><author>rwmj</author><text>Isn&amp;#x27;t that just the same thing, but using a natural process (sweating) rather than phase change in a refrigerant?</text></comment>