San Diego Gas & Electric customers face new time-of-use rates beginning Nov. 1, 2013, under a California Public Utilities Commission decision Dec. 20. The rates are mandatory for small commercial customers and voluntary for residential customers. The actual charges are being worked out in a separate proceeding--the utility’s general rate case--but under this week’s decision they will vary at different times of the day. The time-of-use rates come six years after regulators approved $5 billion for investments in “smart” meters that are supposed to help consumers trim their power usage in response to price signals. The meters are to alert customers when power rates are high due to extreme demand, providing an incentive for conservation that can cut emissions and in the long run minimize the need to build new power plants. Since then there has been little movement in the state toward time-of-use rates, particularly for residential customers. Under this week’s decision, SDG&E would get a budget of $92.7 million to implement the rates--trimmed from the initially requested $118 million. It would recover the money from its customers. The utility would use a portion of the money to educate customers about the new dynamic rates, including through shadow billing that would show the difference between the charges under the new versus old rate structure. On Nov. 1, 2013, residential customers are expected to be able to choose whether to remain under their existing tiered usage rates or opt into a time of use pricing plan or a critical peak pricing plan for the 18 days of the year when electricity use peaks. Small businesses face mandatory time-of-use rates or critical peak pricing rates beginning Nov. 1, 2014, under the decision.