I was £137 in credit so started to pay £5 for the summer months instead of £55. Scottish Power did not like this because they like to accrue large sums of cash from the customer; then the customer has to go through the stress of clawing back what is 'in credit'. Scottish Power then upped my electric bill overall by cobbling together two sums - the meter and tariff science is no more than a cheap racket. After writing to the CEO, they admitted they had had responded poorly but could still not advise which meter reading number I key in on my online account: Rate 1 or Rate 4. The meter readings never seem incorrect when they are taking too much, only when they take to little. In fact I have no faith in Scottish Power at all, it appears that all the Energy companies are rotten to the core.