Planning to drive Hybrid on gas until I get solar

A

ace base

Member
Hello,

I am planning to purchase Clarity in coming days, after calculating various things, its clear that driving on gas would be better in SoCal case until I have solar.

I am SoCal here the electricity rates offered by SDGE are ridiculous compared to our neighbors in LA.

GAS: $3.75/gallon

Standard rates: 23c upto 310 kwh/month, 45c from 310-800 kph/month, 54c 800 + kph/month. This is the plan I am on and use about 250kwh, untill the Air conditioning gets used when heat kicks in

Time of use (TOU2) rates: 23c kwh (super off peak, 12am - 4am), 28c kwh (off peak), 54c kph (peak 4pm-9pm)

mpg = 9c/mile
Mpge = 14c/mile (@45 kwh likely my case), 7c/mile (@ 23c kwh, not possible to charge at this rate)

I won't be able to switch to TOU2 until later this year, unfortunately one can change the plan only once per year.

My situation
Daily roundtrip commute 42
No charging at work, not willing to drive/wait somewhere else to charge
Need to buy a car now
Clarity looks nice and comparable to other mid size Hybrids we are interested in (Camry). With tax rebates Clarity comes out ahead
Looking to get solar late next year

Appreciate thoughts
 
My initial reaction to the title of this post was: "How could it possibly make sense to drive the Clarity with gas only?"

That was before I read list of your current electrical rates, that seem stunningly high to me, and your commuting circumstances. We are currently paying a 7/24 rate of about 12c per kWh to our utility in North Carolina, and back in SoCal before we left in 2005, our local rate was 11.2c per kWh, so I was shocked to read your rates. SoCal utility prices must have skyrocketed since we left.

I feel your pain, and I now understand that it does make sense for you to defer your use of electrical power until you can utilize TOU2, or solar. Long term, I think you will be very happy with the Clarity.
 
Not sure what you mean here: "(@ 23c kwh, not possible to charge at this rate)"

The simplified assumption would be to assume the car gets 47 mpg on gas which is also the miles the car will go on electric (mpc). Then you just have to compare the total charge cost to the cost of a gallon of gas. If gas is $3.75, then the cost to charge needs to be less than about $0.25/kWh ($3.75/15kWh, assumes 1kWh of efficiency loss). TOU2 with charging between 12am-4am would definitely be cheaper than gas but you'd need to install a 240V EVSE to keep within that 4 hour window, otherwise if you just charge with the provided 120V adapter, 8 of your charge hours would be at $0.28/kWh.

Here's how that might pencil out with charging starting at 9pm on 120V:
9p-12a: 3h x $0.28/kWh x 1.2kW=$1.01
12a-4a: 4h x $0.23/kWh x 1.2kW=$1.10
4a-9a: 5h x $0.28/kWh x 1.2kW=$1.68

So adding up those three time spans, the cost is $3.79 per charge. That's close enough to the gas price to make it wise to do it. However, with your a/c usage in that 4-9pm timeframe, your overall bill could be higher under TOU2 than the plan you have now. Maybe SDGE provides some tools to evaluate how your past usage might help determine if TOU2 is better for you than your current plan (this evaluation doesn't have to take into account the car charging; the unknown is your 4p-9p usage).

Here's some additional guidance for using public charging stations:

Gas@$3.75/gal is trumped by
Electrons if charge cost ≤ $1.85/hr or ≤ $0.06/min or ≤ $0.25/kWh (assumes 240V EVSE can charge at 6.6kW)
 
Steven B said:
Not sure what you mean here: "(@ 23c kwh, not possible to charge at this rate)"

The simplified assumption would be to assume the car gets 47 mpg on gas which is also the miles the car will go on electric (mpc). Then you just have to compare the total charge cost to the cost of a gallon of gas. If gas is $3.75, then the cost to charge needs to be less than about $0.25/kWh ($3.75/15kWh, assumes 1kWh of efficiency loss). TOU2 with charging between 12am-4am would definitely be cheaper than gas but you'd need to install a 240V EVSE to keep within that 4 hour window, otherwise if you just charge with the provided 120V adapter, 8 of your charge hours would be at $0.28/kWh.

Here's how that might pencil out with charging starting at 9pm on 120V:
9p-12a: 3h x $0.28/kWh x 1.2kW=$1.01
12a-4a: 4h x $0.23/kWh x 1.2kW=$1.10
4a-9a: 5h x $0.28/kWh x 1.2kW=$1.68

So adding up those three time spans, the cost is $3.79 per charge. That's close enough to the gas price to make it wise to do it. However, with your a/c usage in that 4-9pm timeframe, your overall bill could be higher under TOU2 than the plan you have now. Maybe SDGE provides some tools to evaluate how your past usage might help determine if TOU2 is better for you than your current plan (this evaluation doesn't have to take into account the car charging; the unknown is your 4p-9p usage).

Here's some additional guidance for using public charging stations:

Gas@$3.75/gal is trumped by
Electrons if charge cost ≤ $1.85/hr or ≤ $0.06/min or ≤ $0.25/kWh (assumes 240V EVSE can charge at 6.6kW)
Click to expand...
Do you think the car will get 47 mpg when it is not aided by the battery/motor? Will the Atkinson cycle engine get lower mpg when it has to propel the car from a standing start?
 
ace base said:
Hello,

I am planning to purchase Clarity in coming days, after calculating various things, its clear that driving on gas would be better in SoCal case until I have solar.

I am SoCal here the electricity rates offered by SDGE are ridiculous compared to our neighbors in LA.

GAS: $3.75/gallon

Standard rates: 23c upto 310 kwh/month, 45c from 310-800 kph/month, 54c 800 + kph/month. This is the plan I am on and use about 250kwh, untill the Air conditioning gets used when heat kicks in

Time of use (TOU2) rates: 23c kwh (super off peak, 12am - 4am), 28c kwh (off peak), 54c kph (peak 4pm-9pm)

mpg = 9c/mile
Mpge = 14c/mile (@45 kwh likely my case), 7c/mile (@ 23c kwh, not possible to charge at this rate)

I won't be able to switch to TOU2 until later this year, unfortunately one can change the plan only once per year.

My situation
Daily roundtrip commute 42
No charging at work, not willing to drive/wait somewhere else to charge
Need to buy a car now
Clarity looks nice and comparable to other mid size Hybrids we are interested in (Camry). With tax rebates Clarity comes out ahead
Looking to get solar late next year

Appreciate thoughts
Click to expand...
Makes sense to me. Our rates are $0.15/KWh 24/7. When we installed solar for the house the payback on the solar system didn't look too attractive until we added the idea of buying a PHEV. The combination of power to feed the house during the day, plus charging the Clarity, makes very good economic sense. We sized the solar for the house only so being able to charge the Clarity too means the car charge is zero additional cost. We drive for free 80% of the time.

I just heard yesterday that something like 90% of PHEV/BEV charging happens at the home. We've never once, in 10,000 miles, used a charge station away from home. It's interesting to consider this statistic in light of fuel cell cars. The auto manufacturers seem hell-bent on producing hydrogen fuel cell cars. I was once on that bandwagon but have come to the conclusion that BEV will win when charge times are 15 minutes or less. If 90% charging happens at home the number of hydrogen stations isn't going to help. People will want hydrogen production at their home. We already have power at the house to charge batteries. It seems silly to use electricity to generate hydrogen so it can produce electricity in the car.

We've been very pleased with our solar system. I'm surprised how it continues to generate power even on cloudy days. Our system averages about 50KW per day with 20 panels. We are winning against the grid. Soon we'll have to kick on the house AC which will change the formula though. I hope the solar can at least greatly reduce our electric bill during the hot months when the AC works hard 24 hours a day.

I think you're making a wise decision.
 
ace base said:
Hello,

I am planning to purchase Clarity in coming days, after calculating various things, its clear that driving on gas would be better in SoCal case until I have solar.

I am SoCal here the electricity rates offered by SDGE are ridiculous compared to our neighbors in LA.

GAS: $3.75/gallon

Standard rates: 23c upto 310 kwh/month, 45c from 310-800 kph/month, 54c 800 + kph/month. This is the plan I am on and use about 250kwh, untill the Air conditioning gets used when heat kicks in

Time of use (TOU2) rates: 23c kwh (super off peak, 12am - 4am), 28c kwh (off peak), 54c kph (peak 4pm-9pm)

mpg = 9c/mile
Mpge = 14c/mile (@45 kwh likely my case), 7c/mile (@ 23c kwh, not possible to charge at this rate)

I won't be able to switch to TOU2 until later this year, unfortunately one can change the plan only once per year.

My situation
Daily roundtrip commute 42
No charging at work, not willing to drive/wait somewhere else to charge
Need to buy a car now
Clarity looks nice and comparable to other mid size Hybrids we are interested in (Camry). With tax rebates Clarity comes out ahead
Looking to get solar late next year

Appreciate thoughts
Click to expand...
I think you will miss the best part of the car- driving in EV, it is delightful. Its worth it even if it costs a little more.
 
Keep in mind that once you go solar, under the new rules you will have to shift to SDG&E's solar TOU - DR-SES schedule (which is for all intents and purposes - at least today anyway - the same rates as the EV TOUs).

I don't think I'd be happy knowing I could be on EV but I can't because of circumstances. But that's just me. You can still plug into your 110v. But it probably won't be truly satisfying until you can get that car charged in 2 hours and do it at home. Otherwise, there aren't any real downsides to getting the car now. You'll get the $7500 tax break next year and if you qualify (meaning you don't make too much money) you'll get a $1500 state rebate. That brings the cost of your vehicle down considerably.

Slippery slope coming up: If you do go solar, you may need to upgrade your service panel to 200A. If that's the case, the cost can be offset by the 30% tax break - if you also run a 240v line or two to the garage at the same time, have your electrician put it all on the same quote. Think about whether or not you want to hard or softwire in an EVSE for home charging, and do it at the same time - put it on the same bill. Roof need some work? That'll be covered too. Essentially, any work that needs to be done to accommodate the solar install is covered. Surprisingly, it includes tree trimming or removal. Don't wait forever to do this, however. The tax breaks for solar installs start falling off pretty soon (from 30%). Be sure you consider a battery, too. You won't consume all the energy you produce during the day. It's best to save that energy to offset the 5 hours each day when the 54¢/kWh SDG&E summer ripoff kicks in.

Lots of people who considered a Prius Plug-in when it first came out had the same questions as you do. Often it had to do with potential owners who lived in apartments or in a place where there was no possibility to plug in at home. Essentially, your PHEV should act as a hybrid vehicle (it'll charge the battery enough because of the way the HV system works ) And you can also choose to use a little more gas - in HV Charge mode - and have the ICE charge the battery to 58%. When you have an opportunity to plug in - say at a mall or some other place where there's a public EVSE - then you can do that if you want. Unfortunately, San Diego doesn't have a plethora of public EVSEs and charging stations now, but it's slowly changing.
 
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You might want to consider the 2019 Honda Insight that gets 55 mpg with 151 hp and 197 lb ft of torque. It starts at about $24000 and that includes Honda sensing. It's also a beautiful car that is larger, more powerful, and handles better than the Prius, Niro, and Ioniq. It goes on sale soon (see the reviews online) so it might fit your needs better.
 
PHEV Newbie said:
You might want to consider the 2019 Honda Insight that gets 55 mpg with 151 hp and 197 lb ft of torque. It starts at about $24000 and that includes Honda sensing. It's also a beautiful car that is larger, more powerful, and handles better than the Prius, Niro, and Ioniq. It goes on sale soon (see the reviews online) so it might fit your needs better.
Click to expand...

I thought about that too, but I think the OP is interested in maximizing rebates and tax credits. The Insight - being a non-plug-in hybrid - won't get those.
 
I think for most times of the year you will be hard pressed not to get 60 EV miles to a charge... that changes the dynamic a bit?


Sent from my iPhone using Inside EVs
 
jdonalds said:
Do you think the car will get 47 mpg when it is not aided by the battery/motor? Will the Atkinson cycle engine get lower mpg when it has to propel the car from a standing start?
Click to expand...

My estimates were based on the battery never falling to zero. Operating totally in HV (granted due to Honda not allowing us to change the default mode, you have to remember to set it every time powering up), I would think it would take a few weeks to drain the battery and would assume that some plug-in time could be found at home or while eating out, etc. Even if you never charge via the plug, you can charge to 58% in HV Charge mode and that mileage estimate is conservative based on what the community has reported for general commuting speeds (very little 70mph driving), so running HV Charge a few times a month shouldn't drastically affect the mileage.
 
Thanks all for sharing your thoughts. We did drive Prius prime, but did not like it. It also felt small and ride a bit rough coming from over current Accord.

@jdonalds "(@ 23c kph, not possible to charge at this rate)"
I meant that 23c kwh tier is already consumed by home electric use, going to TOU@ can make this work, but unsure how the electric bill may look like.

@bfd - Yes solar is way more slippery slope. The roof will need replacement at some point in next 5-10years, but there is a possibility of ground mounted solar, so that could separate roof with solar or do partial roof with solar and remainder later, although this may not be worth the hassle. In some ways this is too much hassle to accomodate cheaper charging. If HV mode pans out fine, it could work with few charges a month at home. oh well!

I am looking at this as a bit more fancy car, but a tad less expensive than comparable hybrids (accord/camry). All owners in this case are exposed to risk of reliability depending on how long they have it. My current thinking is to run this as car as it will go hopefully 150k. Unfortunately my current accord v6 with whopping 18mpg and leaky transmission is on its way out at 120k.
 
When I bought the car, I thought I’d never charge at public stations either. But I’ve found with the PlugShare app set to find free stations, I frequently can find charging stations near places I shop and work. Not sure about your area, but I live in rural NC and am pleasantly surprised at how infrequently I need to charge at home (no more than 15 days/month).
 
In San Diego region no free charging as electricity rates are nuts here. Hotels offer it to their patrons, so no dice for us.
 
How much more will it really cost driving on electric? Even if it is 10% more on electric I would still use it to a avoid burning gas.

Crazy rates, mine actually get lower if I use more, but if you bump to that 54 cent it would be a lot more. We are like 12 cents here.
 
ace base said:
In San Diego region no free charging as electricity rates are nuts here. Hotels offer it to their patrons, so no dice for us.
Click to expand...

There are some scattered Volta free EVSEs around, and some Kohl's were early adopters and still have a few free slots. But for the most part, rates are generally 49¢/kWh (if you're a Blink member) at the Blink stations that seem to have popped up in various places like IKEA, SDSU, etc. For awhile there were some free slots in the parking area underneath the Convention Center, but I haven't been over there for a year or more. There a few pay stations across the street from UTC as well and a few that seem to be hit or miss in Mission Valley Center (east side). But for a metro area of several million, it's pretty slim. (SDG&E again…)
 
@Viking79 if we assume tier 2 rate of 48c per kWh it’s equivant to buying gas at $7 per gallon.

So the margin here is 100% unfortunately. It gets worse when AC kicks in home and the rates moved up to 54c+

We have been promised a rate increase in coming years by SDGE, so they seem to have learned quite a bit from Enron
 
@bfd yes there are few scattered ones here and there. As not yet an owner I can’t imaging hunting out these free chargers, but who knows how habits may change after owning one.
 
I'm in San Diego too, and I feel the pain. I believe there are a couple free chargers in the 4S Ranch town center, but I haven't tried them.
Not having (yet) solar at home, I got the Clarity only because I can charge for free at work, otherwise it wouldn't really have made economic sense...
 
Whoa, those elwctic rates are quite a bit more but you live in San Diego so I dont feel bad for you.

Sounds like you would be better off doing battery charge mode on your car then topping off at home with your level 1 charger at the time your cheapest rate is.
 
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