Rashin sanyaya na rana

**Rashin sanyaya na rana** (**PDRC**) (kuma sanyaya na radiative, sanyaya na hasken rana, **sanyaya sararin samaniya**, sanyaya radiative, da sanyaya radiatic na duniya) shine amfani da wuraren da ba su da wutar lantarki, masu nunawa / masu fitar da zafi don rage zafin jiki na gini ko wani abu.

An gabatar da shi azaman hanyar rage karuwar zafin jiki wanda iskar gas ta haifar ta hanyar rage makamashi da ake buƙata don sanyaya iska,   rage Tasirin tsibirin zafi na birane,  da kuma rage Yanayin jiki mutum.    

PDRCs na iya taimakawa tsarin da suka fi dacewa a yanayin zafi, kamar tsarin photovoltaic,   na'urorin tattara raɓa, da janareto na thermoelectric.

Wasu kimantawa sun ba da shawarar cewa keɓewa 1-2% na yankin duniya ga PDRC zai daidaita Yanayin zafi. Bambance-bambance na yanki suna ba da damar sanyaya daban-daban tare da hamada da Yanayin yanayi mai matsakaici wanda ke amfana fiye da yanayin zafi, wanda aka danganta da tasirin danshi da girgije. Ana iya haɗa PDRCs a cikin tsarin daidaitawa, sauyawa daga sanyaya zuwa dumama don rage duk wani tasirin "mai sanyaya". Aikace-aikacen PDRC don sanyaya sararin samaniya yana girma tare da kimanin "girman kasuwa na ~ $ 27 biliyan a cikin 2025

An tsara farfajiyar PDRC don zama mai girma a hasken rana don rage yawan zafi da ƙarfi a cikin infrared mai tsawo (LWIR) canja wurin zafi na radiation wanda ya dace da taga na infrared na yanayi (8-13 μm). Wannan yana ba da damar zafi ya wuce ta cikin yanayi zuwa sararin samaniya.&nbsp;

PDRCs leverage the natural process of radiative cooling, in which the Earth cools by releasing heat to space. PDRC operates during daytime. On a clear day, solar irradiance can reach 1000 W/m2 with a diffuse component between 50-100 W/m2. The average PDRC has an estimated cooling power of ~100-150 W/m2, proportional to the exposed surface area.****

Ana tura aikace-aikacen PDRC a matsayin saman da ke fuskantar sama. Kayan PDRC masu tsada masu tsada tare da yiwuwar samar da taro sun haɗa da sutura, fina-finai masu laushi, metafabrics, aerogels, da wuraren biodegradable.

Duk da yake yawanci fari, wasu launuka na iya aiki, kodayake gabaɗaya suna ba da ƙarancin sanyaya.

Bincike, ci gaba, da sha'awar PDRCs sun karu da sauri tun daga shekarun 2010, wanda ya danganta da ci gaba a cikin amfani da photonic metamaterials don kara sanyaya rana a cikin 2014,   tare da karuwar damuwa game da amfani da makamashi da dumama duniya. PDRC za a iya bambanta da tsarin sanyaya na gargajiya (misali, masu sanyaya iska) waɗanda ke cinye makamashi mai yawa, suna da tasirin dumama (zauna waje fiye da sanyaya cikin gida), suna buƙatar samun dama ga wutar lantarki kuma galibi suna amfani da masu sanyaya waɗanda ke lalata ozone ko suna da tasirin greenhouse mai ƙarfi,  

Ba kamar kula da radiation na rana ba, PDRC yana ƙara fitar da zafi fiye da tunani mai sauƙi.

## Aiwatarwa
Wani binciken da aka yi a shekarar 2019 ya ba da rahoton cewa "karɓar sanyaya mai haske na iya rage yawan zafin iska kusa da farfajiya, idan ba duk yanayin ba. "  Don magance dumamar yanayi, dole ne a tsara PDRCs "don tabbatar da cewa fitarwa *ta hanyar* taga na gaskiya na yanayi kuma ta fita *zuwa* sararin samaniya, maimakon kawai zuwa yanayi, wanda zai ba da damar sanyaya na gida amma ba na duniya ba. "

Yanayin hamada yana da mafi girman yiwuwar sanyaya saboda karancin zafi na shekara-shekara da girgije, yayin da Yanayin zafi yana da karancin yiwuwar saboda zafi mafi girma da girgije. Kudin aiwatarwa na duniya an kiyasta su a $ 1.25 zuwa $ 2.5 tiriliyan ko kusan 3% na GDP na duniya, tare da tattalin arzikin da ake tsammani. An haɓaka kayan haɓaka masu ƙarancin farashi don aiwatarwa mai yawa, kodayake wasu ƙalubale zuwa Kasuwanci sun kasance.  

Wasu binciken sun ba da shawarar ƙoƙari don kara yawan hasken rana ko albedo na farfajiya, tare da burin fitar da zafi na 90%. Misali, karuwar haskakawa daga 0.2 (aikin rufin) zuwa 0.9 ya fi tasiri fiye da inganta farfajiyar da ta riga ta nuna, kamar daga 0.9 zuwa 0.97. 
 

## Manazarta