EVALUASI PENGARUH PENGGUNAAN BATUBARA LOW RANK TERHADAP KINERJA UNIT #20 PLTU REMBANG DITINJAU DARI NET PLANT HEAT RATE ( EVALUATION OF THE EFFECT OF THE USE OF LOW – RANK COAL TO THE POWER PLANT’S PERFORMANCE IN TERMS OF NET PLANT HEAT RATE AT UNIT #20 PLTU REMBANG ) - Yogatama, Marga (2015)