Area, A1 = 3 * 24 = 72 kWh

Area, A2 = 15 * 12 = 180 kWh

Area, A3 = 6 * 10 = 60 kWh

Area, A4 = 6 * 9 = 54 kWh

Area, A5 = 5 * 6 = 30 kWh

At load of 0 kW, Amount of energy consumed = 0 kWh

At load of 3 kW, Amount of energy consumed = A1 = 72 kWh

At load of 18 kW, Amount of energy consumed = (A1 + A2) = 252 kWh

At load of 24 kW, Amount of energy consumed = (A1 + A2 + A3) = 312 kWh

At load of 30 kW, Amount of energy consumed = (A1 + A2 + A3+ A4) = 366 kWh

At load of 35 kW, Amount of energy consumed = (A1 + A2 + A3 + A4 + A5) = 396 kWh

Mass Curve

It is energy versus time plot of the cumulative integration of the area under the load curve starting from zero time to the particular time. A mass curve represents the total energy consumed by the load upto a particular time in a day. So, mass curve can be easily plotted from the chronological load curve by to summing up the energy consumed upto different times starting at the zero time. Let us consider the following load curve:

Area, A1 = 2 * 18 = 36 kWh

Area, A2 = 6 * 35 = 210 kWh

Area, A3 = 1 * 24 = 24 kWh

Area, A4 = 3 * 30 = 90 kWh

Area, A5 = 12 * 3 = 36 kWh

At time 6 AM, Amount of energy consumed = 0 kWh

At time 8 AM, Amount of energy consumed = A1 = 36 kWh

At time 2 PM, Amount of energy consumed = (A1 + A2) = 246 kWh

At time 3 PM, Amount of energy consumed = (A1 + A2 + A3) = 270 kWh

At time 6 PM, Amount of energy consumed = (A1 + A2 + A3+ A4) = 360 kWh

At time 6 AM, Amount of energy consumed = (A1 + A2 + A3 + A4 + A5) = 396 kWh

Figure: Mass curve