O le lau o le uila afi (uili) o se tasi lea o vaega autu o masini eletise, e tusa ma le 15% - 20% o le tau atoa o meafaigaluega.O lona mamanu o le a aafia saʻo ai le faʻatinoga ma faʻamanuiaga o meafaigaluega.
O lau ili e masani ona faʻaaogaina i ili, faʻaulu uila, faʻaaʻa aʻa ma compressors turbine.Ua vaevaeina i ni vaega se valu: compressors centrifugal, compressors axial-flow, compressors reciprocating, blowers centrifugal, blowers a'a, ili centrifugal, ili axial-flow ma outou blowers.