Slight miscalculation on electric rates

This week we received our first annual "true-up" electric bill from PG&E.  Since the electricity generated from solar varies from month to month, it is only at the end of a year that you can really see how you came out).  Based on their bill I owe about $25 for the year.  I had previously estimated that I would come out ahead by about $4--see post "Everything is going according to plan" on January 18.

My miscalculation was due to the cost of electricity in December and January.  In these low sun months, we use quite a bit more electricity than the solar panels generate.  This puts us into Tier 2 and Tier 3 for our bill.  In most months the solar panels generate enough electricity to keep our bill down in the Tier 1 baseline rate, which is cheaper than Tier 2 or Tier 3.  I had erroneously assumed that we would be in Tier 1 for the whole year, including December and January.

Still, the $25 extra charge is small; it only adds about 0.4 cents per kilowatt hour (kwh) to our annual cost. This brings our average electric rate, including the cost of the solar--up to 16.1 cents per kwh compared to PG&E's average of 18.6 cents. 

Hopefully, this year we can conserve on electricity better than in 2011.  The main issue that I am concerned about is the pending rate change from PG&E for electric cars.  Stay tuned--the CPUC should make an announcement about this any day now.