This paper investigates the loadability increase of overhead transmission lines (OHLs) equipped with high-temperature low-sag (HTLS) conductors. Compared with traditional ACSR conductors, HTLS conductors allows to get a large increase of the thermal limit, maintaining the same weight and size of the conductors. Of course, the loadability curves increase only in the thermal limit region and, thus, this measure provides a significant advantage only for short lines. However, the advantage provided by HTLS conductors can be extended to longer lines if the voltage drop across the line can be controlled. This can be done injecting reactive power at the receiving end of the line by means of synchronous condensers or static var compensators (SVC). This paper highlights the loadability increase that can be obtained this way in the voltage drop region over a wide range of lengths. Accordingly, HTLS conductors can be better exploited up to much longer line lenghts.