UTILITIES getting prepared and excited for new 'realistic' EVs - GO PG&E !!

[doggydogworld]

4 kW is average. In reality my draw fluctuates from less than 1 kW to more than 10 kW, depending on how many A/C units are running.

4 kW * 24 hours/day * 31 days = 2976 kWh. That's a pretty good forecast of my July usage, assuming the heat wave continues. Maybe a bit less since we'll be gone a couple days next week and I'll push the A/C to 82.

[AySz88]

Did anyone notice the statement near the end of this article: "The load of one of the cars charging is about the equivalent of three homes in San Francisco. It’s taking that much out of the system.” Is this true? Is anyone seeing their electric bills triple?

I'm pretty sure "load" means the power being consumed at any instant (measured in watts or kW), not the total energy (measured in kWh, which is what your bill is). I think that "3 homes" number is plausible, especially overnight - it's maybe even a underestimate. I managed to scrape together enough statistics to estimate off-peak (nighttime) usage in summer for a Long Island "household", and I got that a typical one only draws around 600 watts during the night. The Volt would use 2 "households" when charging with the stock Voltec station, and 4 "households" with a 240 V system charging over 4 hours. It might peak at 6 "households" if it's maxing out a level 2 station.

Here's my math, in case I messed it up!

Off-peak night hours (LIPA [2]): 8PM-10AM weekdays, and all weekends (70% of the time)
Total off-peak hours in a summer (June, July, August, September): 122 days * 24 hours/day * 0.7 = 2050 hours

Proportion of electricity used in night time in summer [1]: 184.7/525.5 = 25.1%

Total summer energy use for an average LI household (2006) [2]: 4000 kWh

Estimated summer off-peak energy use (total over a summer): 4000 kWh * 0.251 = 1255 kWh

Power during summer nighttime: 1255 kWh / 2050 hours = 612 watts

A level 2 charging station draws at max 240 volts * 16 amps = 3840 watts, which would be around 6 "households".
It should average 10.4 kWh / 4 hours = 2600 watts, which is 4 "households".

The "stock" station averages 10.4 kWh / 8 hours = 1300 watts, which would be 2 "households".

[1] NY state stats for July 14, 2011: http://www.ferc.gov/market-oversight/mkt-electric/new-york/nyiso-rto-dly-rpt.pdf
(updates ~daily?)

[2] 2006 LIPA stats: http://www.osc.state.ny.us/reports/pubauth/lipasummer06.pdf

[ClovisVOLT]

Did anyone notice the statement near the end of this article: "The load of one of the cars charging is about the equivalent of three homes in San Francisco. It’s taking that much out of the system.” Is this true? Is anyone seeing their electric bills triple?

In speaking with a SF PG&E rep, she had first hand knowledge of a Tesla owner whose bill did tripple.....but for those of us who pay a bit closer attention to details, I can only tell you that with the E9B rates the per Kwh rate is less than 5 cents (4.3 cents during the summer).

So, even if we go on the high side 5 * 12 Kwh per = 60 cents/charge * 30 days/month = $18 month (or about 5 gallons of gas). The key factor to consider is the E9B rate (to keep all of your Volt power under baseline). There is also a daily charge of 22 cents for the meter (so it's more like 80 cents per day or $24 month total - again, less than 7 gallons of gas).

http://www.pge.com/tariffs/tm2/pdf/ELEC_SCHEDS_E-9.pdf

Anyone who is already in the higher tiers due to current electrical use would be financially silly to not go with the E9B - unless your Solar overgeneration supports the added Volt Kwhs.

By the way, has anyone used a 240V Kill-a-watt to determine the actual real world refill wattage needed from a Voltec?

GO GM, GO VOLT, GO SOLAR, GO E9B!

[Sheffield]

Anyone who is already in the higher tiers due to current electrical use would be financially silly to not go with the E9B - unless your Solar overgeneration supports the added Volt Kwhs.

Actually, PGE has a calculator to let you compare. With E9B you continue your house on a separate meter with an E1 rate or whatever else you qualify for. With the E9A your whole house gets the EV time of use rates. If you are at the higher tiers and can move usage off peak the savings of E9A can be much greater than with E9B.

My monthly PGE bill actually decreased after I got the Volt and 240V EVSE under E9A.

[ClovisVOLT]

Ahhh, good point.....I hadn't viewed the change from base rate plans to E9A as being the decision point (just figured that anyone who had a legitimate benefit of TOU rates had already made the switch, but could see a light electric Volt user actually doing better with E9A in some situations (esp if there's a large enough cost for the 2nd meter).

Since we were already on the E6 TOU rate, running the numbers made it very clear that giving the Volt it's own baseline would keep us in the VERY low overnight baseline costs permanently.

http://www.pge.com/about/environment...es/index.shtml

Although the summer baseline allowances are pretty generous, just the Volt charging alone would eat up most all of the winter baseline and then (if on E9A) electricity starts to get a bit pricier....do you have the comparison calculator available via a link? This was not on-line yet, and I'd be curious what it would conclude for my circumstances....does it take into consideration the baseline differences in rate areas and seasons?

My total PG&E electrical true-up at the end of the year was $11 (or 3 cents per day) on the Solar meter side (even with 2 months of straight use by the Volt using the 110V plug to ensure no net credit). The average electric cost on the E9B-EV meter side has been around $20/month. Not sure you can do much better than cooling a 4000 sq ft house in 100 degree average summer temps with pool (neighbors had been spending $900/month for PG&E on their place) along with fueling your primary vehicle at an average monthly cost of under $35 (one VOLT tank of gas)....but always willing to raise the bar further. Appreciate the link!

GO GM, GO VOLT, GO SOLAR, GO E9* rates