Efficiency is a measure of how much work or energy is conserved in a process. The efficiency is the energy output, divided by the energy input, and expressed as a percentage. It is calculated as:
efficiency (%) = (useful energy out ÷ total energy in) x 100
efficiency (%) = (((1300x9.8x1.8)/24x1000 )÷ 1.5 kW ) x 100
efficiency (%) = 63.7%
Hope this answers the question. Have a nice day.