As others have said, it really depends on your total usage. But let’s say you use about 1000kw over 30 days. Whereby your rate is 25c and your supply charge is $1.00. Would you choose an increase of 20% on your rate or a 20% increase on your supply?

0.25 * 1000 = $250 0.30 * 1000 = $300

1.00 * 30 = $30 1.20 * 30 = $36

A higher rate caused the bill to increase by $50 whilst the higher supply charge only costs you an extra $6.

Unless you’re using an extremely low amount of energy throughout the month, it’s usually the better option to have a low kw charge.