Get ready to open your wallet a little wider this month. Hydro rates are set to increase by 4 percent starting today. The government claims the increase is due to the mild winter and lower consumption rates. We get a price adjustment every May 1st. This one, says the Ontario Energy Board, will be about $3.13 a month for the average residential or small business customer. The Board takes into account such things as the amount of power customers are expected to use in the next six months, how well they predicted consumption over the previous six months and the types of power of power available (nuclear, natural gas, hydro-electric, renewable) and the various costs. The rate for off-peak use (8.7 cents per kilowatt hour) is half of what it is during peak periods (18 cents per kilowatt hour). Off-peak periods are between 7pm and 7am weekdays, all-day on weekends and holidays.