Unfortunately, the Ca mandates for clean energy make power a lot more expensive. I don't know exactly how they control the power in the western grid, but the decision was made not to purchase power from any outside utility that uses coal.
You likely used just enough charging your Volt to get you into a top tier. Most companies use 3 tiers, but some use only 2. Top tier with most is well over .40 a KWH, and may be closer to .50 once you add in all the various fees.
Sucks if you're in an area where you need to run A/C much.
TOU will make the average bill higher for LADWP customers, since about the only thing you can schedule in the wee hours would be vehicle charging. Trouble is, that arrangement makes daytime rates a lot higher, and most don't need A/C much at night.
A couple perks like discounts on chargers aside, the average customer gets penalized for having an electric car if you're an LADWP customer.
PG&E does have some sort of discount for electric car users, but I'm not sure exactly what that is. I have a house on the Central Coast in their territory where my electricity is really cheap because I don't use enough to get out of the first tier (A/C not needed up there), but the couple times I had the Volt up there, just a few charges put me into the second tier.
If I were going to be in the LA area much longer I would go solar, but just like any other investment, it takes a while to pay off.