Concept:
Average load is:
\[
\text{Average load}=\frac{\text{Energy consumed}}{\text{Time}}
\]
Step 1: Given energy consumed in 24 hours:
\[
E=480\ \text{MWh}
\]
Step 2: Time duration:
\[
t=24\ \text{h}
\]
Step 3: Average load:
\[
P_{\text{avg}}=\frac{480}{24}
\]
\[
P_{\text{avg}}=20\ \text{MW}
\]
Therefore:
\[
\boxed{20\ \text{MW}}
\]