▁This ▁H ERS ▁is ▁mand atory ▁for ▁government ▁buildings , ▁big ▁commercial ▁complex es ▁and ▁those ▁buildings ▁applying ▁for ▁public ▁retro fit ▁fund ing ▁or ▁green ▁label . ▁this ▁H ERS ▁consist ▁a ▁star ▁rating ▁scheme , ▁r anging ▁from ▁ 1 ▁to ▁ 5 ▁star . ▁As ▁per ▁this ▁H ERS , ▁more ▁the ▁star , ▁more ▁will ▁be ▁the ▁energy ▁efficiency ▁of ▁the ▁building . ▁The ▁rating ▁level ▁of ▁buildings ▁is ▁determined ▁in ▁three ▁parameters ; ▁ 1 ) ▁Basic ▁Items ▁: ▁refers ▁to ▁the ▁reg ulated ▁energy ▁use ▁per ▁square ▁meter , ▁obtained ▁by ▁computer ▁model ing ▁or ▁measurements . ▁ 2 ) ▁Re quired ▁Items ▁: ▁refers ▁to ▁minimum ▁performance ▁requirements ▁for ▁building ▁en velop ▁and ▁He ating ▁Vent ilation ▁and ▁Air - Condition ing ▁( H V AC ). ▁ 3 ) ▁Optional ▁Items ▁: ▁refers ▁to ▁the ▁additional ▁energy ▁management ▁system ▁which ▁are ▁not ▁mand atory ▁in ▁the ▁rating ▁scheme . ▁it ▁covers , ▁the ▁application ▁of ▁renew able ▁energy , ▁innov ative ▁energy ▁efficient ▁techn ologies . ▁ ▁Den mark ▁In ▁Den mark , ▁the ▁energy ▁rating ▁scheme ▁are ▁in ▁existence ▁since ▁ 1 9 8 1 . ▁Den mark ▁is ▁the ▁first ▁country ▁in ▁Europe ( E U ) ▁to ▁begin ▁issu ing ▁Energy ▁Performance ▁certific ates ▁( E PC s ). ▁The ▁E PC s ▁are ▁mand atory ▁in ▁all ▁types ▁of ▁buildings ▁in ▁Den mark . ▁The ▁rating ▁system ▁in ▁Den mark ▁includes ▁three ▁parts . ▁ ▁The ▁first ▁part ▁of ▁rating ▁consists