E-9A vs E-6 rate for PG&E Model S owners with Solar

E-9A vs E-6 rate for PG&E Model S owners with Solar

I am currently have an 8.4kW PV system and am on a PG&E E-6 rate. Since I took delivery of my Model S, I've been considering switching to an E-9 rate to get the very low off-peak rates for charging (from midnight to 7AM). However, because they shift the peak hours later its not clear this is a win since some of my best generating time that is peak on E-6 becomes partial peak on E-9. Also some time after dark that is partial on E-6 is peak on E-9.

Has anyone on this forum done an analysis of this. A quick calculation suggests that unless I do *a lot* of charging off peak, I'm better off on the E-6 rate.

Also, E-6 is clearly preferable to the new EV rate that will ultimately replace E-9.

JBMoney13 | 4 avril 2013

E6 is better. Peak hours until 9pm is just not worth the risk. I have Solar with e6, great combination. PG&E owes me money. :-)

William9 | 4 avril 2013

I'm going to be pulling the trigger on solar in May. But here's my problem. The house is empty in the winter as we head to Arizona. Any downside to E-6 or E-9 in that case?

cpetrush | 4 avril 2013

Consider AC use in the summer. Peak rates will kill you on E-9. It will only be a good idea if you don't use much power, esp. AC, during peak.

shs | 4 avril 2013

In our case, our biggest use of electricity is heating on winter nights via our geothermal heat pump, and because of our elevation and design of our house, we don't need to use the AC very often in the summer. So, I am guessing that the E-9A rate will work best for us, as it should greatly reduce the cost of heating in the winter. Our solar panels will make less $ on summer mornings and more in the afternoons. Only problem for us may be cooking and watching TV on summer evenings as my home theater amp draws lots of power and does generate some heat, and that is the very high $ time. Anyway, that is what we are now signed up for. I am figuring that the switch to EV-A will be a wash with the E-9A for us.

Electron | 4 avril 2013

Cpetrush, with solar you *want* high peak rates.

mcptwo | 4 avril 2013

PG&E and the California Public Utilities Commission have established dramatically different "Baseline" values for different areas of California. If you go to the link:

You will see that the central valley receives about twice as much baseline/low cost power as the coastal areas. This was probably based on the greater need for air conditioning in those areas. There are also exceptions for medical need that allow greater baseline quantities.

Now that EV's are being introduced into the mix, we need to lobby the California PUC to allow greater baseline quantities for the entire state during "off peak" hours. This would be a much simpler solution that E9 meters or EV rates, and would encourage EV charging during "off peak" hours.

lov2krz | 4 avril 2013

I'm sticking with E6. I may only over produce 1200 kWh per year (7.7 kWh PV) the rate is almost 4 times the off peak rate. PG&E only pays 3.3 cents per kWh over produced (at true up) but credits ~23 cents /kWh over produced. I estimate my MS will use 4000-5000 kWh per year so my operating fuel cost for the car may be $100 at the true up. Since I over produce it doesn't make sense to go to a higher Peak and partial peak rate schedule to save 2 cents/kWh off peak.

mcptwo | 4 avril 2013

We have been on E7 for 30 years. And will not be changing to E9. With the more restrictive E9 hours, the E7 rate is not much different. But even at off peak we are paying about 0.26 /Kwh to charge our Model S.
I would get a second E9 meter exclusively for EV charging if we were not 500 feet underground from the street.

That is why we want more "off peak" Baseline.

I wish we had other options, but living in a redwood forest, has its solar drawbacks. I have thought of a dam on the creek but Fish & Game would object. All lighting is LED, Heat & Cooking = propane.

PG&E bill prior to Model S = $75.00 / month average
PG&E bill after Model S = $200.00 / month

crttnarayan | 4 avril 2013

Also solar and e6. No bills for the last two years. Curious to see what happens later this month when I get my MS

DonS | 4 avril 2013


Please explain "PG&E only pays 3.3 cents per kWh over produced (at true up) but credits ~23 cents /kWh over produced."

I am trying to understand PGE's terms since I am considering solar as well as changing rate plans, and there are more variables than I can follow.

shs | 4 avril 2013


The way I think about it is that one should size the system to not over produce electricity as PG&E pays back for yearly overproduction (at true up) at the very low wholesale rate.

On the other hand, juice produced during a summer afternoon subtracts directly from your usage during that time period, and excess juice during that summer afternoon is credited at the high $ rate - 10 times the wholesale rate. So one is using $ generated during the high $ times when the solar panels are producing to generate a credit in $ that will pay for usage during low $ time periods, e.g. while you are charging your MS at night at essentially the wholesale rate. The other advantage of solar is that you are much more likely to say at or closer to baseline rates thus keeping overall rates down.

What is interesting about the new proposed EV-A and B rates is that the rates are no longer tiered and the concept of baseline rate goes away. They are doing this so that one does not have to worry that charging your car drives you into the higher tiers.

crttnarayan | 4 avril 2013

Also solar and e6. No bills for the last two years. Curious to see what happens later this month when I get my MS