cwerdna
Well-known member
Sorry, I should've been more specific. On a Leaf, charging at 120 volts is less efficient than 208 or 240 volts.RegGuheert said:
Please help! Will L2 charger use less kwh/energy than the Trickle charge?!
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RegGuheert
Well-known member
Sorry for the misunderstanding! I see now that you meant input voltage, not output voltage.cwerdna said:
We are putting a lot if effort into picking straws on what basically comes out to a 5% to 10% savings on electricity balanced against the $5 to $20 per month one may spend home charging a Leaf. We are only realistically talking about 25 cents to $2 per month in savings for many folks. Even at the highest numbers we are talking about $24 dollars a year saved on electricity balanced against purchasing a $300 to $500 charger, paying for a permit and a licensed electrician to put in the line to power it bringing the final L2 cost to about $750. It could take about 30 to 60 years to break even on the investment based on the L2 saving enough money to make up for the cost of installation by saving electricity.
I just received my Charge Point Summary for September and its shows that the average EV driver in Florida uses 60 kwh per month which only comes to $6.60 based on local daytime power rates. The average savings if one was charging at home and paying the electric bill after installing an L2 instead of using the L1 would be about 60 cents per month. Here the average user may not in a lifetime save enough money on electricity to cover the expense of installing an L2.
Bottom line is that L2 is for convenience as you usually will not see such savings on the power bill to realistically pay for it along with its installation in normal home use.
Thankfully we have free charging at work which has so far been sufficient for most of my needs so I rarely ever need to charge at home.
I just received my Charge Point Summary for September and its shows that the average EV driver in Florida uses 60 kwh per month which only comes to $6.60 based on local daytime power rates. The average savings if one was charging at home and paying the electric bill after installing an L2 instead of using the L1 would be about 60 cents per month. Here the average user may not in a lifetime save enough money on electricity to cover the expense of installing an L2.
Bottom line is that L2 is for convenience as you usually will not see such savings on the power bill to realistically pay for it along with its installation in normal home use.
Thankfully we have free charging at work which has so far been sufficient for most of my needs so I rarely ever need to charge at home.
smkettner
Well-known member
Yes you will save a modest amount of electricity with L2.
Far more important is the vehicle usability goes way up with L2.
Far more important is the vehicle usability goes way up with L2.
Maybe the OP can make the title of this topic a bit less dramatic?
smkettner said:
Exactly! There is no horrible bleeding using the L1 compared to the L2 just a modest difference overall in electrical usage.
Usability goes up even more when businesses install free L2 and Quick chargers to attract customers so that the 90 mile range (currently where I appear to be with my 2014) becomes less limiting. At work I plug in after lunch every few days or when I plan to run errands that evening so I rarely charge at home however on weekends if I am running errands and such after the initial charge at home having more public charging stations around is the bigger issue that one may need "help!" with.
A viable portable pop up solar charger may be a bigger gain for me than spending money on an L2 at home. It would be very convenient if the car could gain some charge sitting their parked while I am fishing, hiking, photographing a garden, etc where there is no public charging available.
TimLee
Well-known member
True, but speed of charging at home is an important convenience for many.RockyNv said:
Convenience is a highly individual determination.
For a very large % of people it is best to have 240V EVSE in case you need the speed sometime.
You are also overlooking safety.
L1 is intended for infrequent emergency or convenience use.
There have been fires.
120V has had some safety problems.
See http://www.mynissanleaf.com/viewtopic.php?f=27&t=15784&hilit=fire&sid=4debcdeec268fe72bd5836ffa4b0532e#p352567 about potential risks.
L2 which often is newly installed is lower risk.
TimLee
Well-known member
Where have you found one of those that is very practical?RockyNv said:
Takes a pretty big panel area to do much.
RegGuheert
Well-known member
That's how much ChargePoint's average customer consumes away from home in a month. In fact Our LEAF uses about 200 kWh of electricity each month, and that is for traveling only about 8000 miles per year, which is well below average. 12,000 miles per year would require about 300 kWh per month, or about $36/month at $0.12/kWh. That's with a 3300W L2 charger.RockyNv said:
If you drove the same 12,000 miles using an L1, you would pay $36*0.91/0.78=$42 per month, or $6 per month or $72/year more for electricity.
Someone living in Hawaii driving the LEAF an average number of miles would save over $200/year by charging from L2 rather than L1.
RegGuheert said:
That's still over a decade just to break even for the 12,000 mile driver however sub 100 mile per charge electric car drivers are more likely to drive the EV only 5,000 to 6,000 miles per year. Like I said still no major bleeding that would justify dropping $1,000 installed for an L2 charger at home mainly because it uses a little less electricity than an L1.
I believe the L1 would only cost 13% per month or $4.60 more based on the well above average Leaf driver since most that I see coming off lease around hear are 3,000 to 5,000 mile per year cars and not 12,000 mile cars. Its fairly rare to see even a 2011 leaf after almost 6 years on it with much over 32,000 miles.
If I told my wife that I needed to install an L2 because the L1 used too much electricity she would immediately ask when we would break even on the investment and then at what rate would the payback accrue at after that (she was a staff accountant and accounts payable specialist for a major corporation). If I told her break even in 10 to 15 years if I drove double what I do now to commute to work and 30 or so years if I just drove whats been the norm and then after that we would see a $36 to $72 annual dividend she would rightly consider having me committed.
TimLee said:
Holy Grail but one can still wish for a practical breakthrough or a viable personal Mr. Fusion device. How about coating the cars with photo-voltaic paint? Someone would just have to invent the paint and we'd have it made.
NASA is making great strides using waste heat and smaller reactors to generate power on the fly using Sterling Engines. In the Eastern Europe they are building these into small water heaters to spin Sterling Generators from the heat bleed-off from the water tanks and pilot lights,
Maybe even a modification of the Prairie Generator could be worth while for mobile charging.
cwerdna
Well-known member
Similar to the Hawaii case, electricity is very expensive in PG&E land. http://www.mynissanleaf.com/viewtopic.php?p=155519#p155519 was a calculation done for me long ago.RegGuheert said:
Now we have fewer tiers and our rates are even higher. See page 1 of https://www.pge.com/tariffs/tm2/pdf/ELEC_SCHEDS_E-1.pdf for our non-TOU rates.
I'm in area X, code B of https://www.pge.com/en_US/residential/save-energy-money/help-paying-your-bill/longer-term-assistance/medical-condition-related/medical-baseline-allowance/understanding-baseline-quantities.page. So, in "summer", on E-1 baseline is 10.1 kWh/day or 10.9 kWh/day in "winter". So, for 30 billing days in "summer",
- every kWh below 303 kWh is at the tier 1 rate of 18.205 cents
- every kWh above 303 is at the tier 2 (101% to 200% of baseline) rate which is currently 24.081 cents
- every kWh above 606 is tier 3 at 39.99 cents/kWh
If household gets pushed into tier 3 due to an EV, the marginal cost per kWh is very high at 39.99 cents/kWh. The CPUC lets (forces?) PG&E to set crappy baselines so that most people aren't able to stay within baseline/tier 1.
From https://www.pge.com/en_US/residential/save-energy-money/help-paying-your-bill/longer-term-assistance/medical-condition-related/medical-baseline-allowance/understanding-baseline-quantities.page
Average US power usage per residential customer is around 900 kWh per month and at 12 cents per kWh that comes to around $100 for me except for during the worst of the summer. I installed a dual compressor straight cool AC unit at the house to keep cooling costs to a minimum (heat pumps are not a worthwhile investment at this latitude), have gone LED for most interior lighting, put reflective roofing on the house, thermo-pane windows all around with shades to limit heat intrusion, use a clothes line instead of the dryer and changed cooking along with water heating to gas.
At work its 7 cents per kWh which my employer does not charge for so I do 99.9% of my charging there. I vetted all this out before purchasing the Leaf and save about $40 per month on fuel over driving my 40/50 mpg Diesel Fiat 124 Spider which I was driving daily but really is not the best choice as a daily commuter. Since I needed another more reasonable car for commuting anyway a used 2014 Leaf came up for me as a viable option to commute cheaply to work within the budget I had already set for this purpose. The next level would be when the roof next needs a re-do to consider solar hot water and electric with a subsidiary and use that to defray the cost of replacing the roof since it will need to be re-done in part during the conversion anyway.
When I suffered a crippling disability from a ladder accident I had to move from New England to an area with a more stable barometric pressure. San Diego California was one of the candidates however utility rates were too high there so I passed and chose a location where the utility rates and taxes were more reasonable.
Yes there may be a few areas in the country where due to insane electric rates you may break even on electrical savings on an L2 over an L1 in about a decade but even that is not good enough on its own to justify the costs.
Its still mostly a convenience upgrade unless you live in an area where the utility company or State basically installs the L2 for free or pretty close to it. Then of course it makes perfect economic sense. Where I live the rates are so low that they do not provide free L2 chargers however a bit South of here the rates are a tad higher and the power company does basically give away the L2 chargers and subsidize their installation if the person telling me this is correct.
At work its 7 cents per kWh which my employer does not charge for so I do 99.9% of my charging there. I vetted all this out before purchasing the Leaf and save about $40 per month on fuel over driving my 40/50 mpg Diesel Fiat 124 Spider which I was driving daily but really is not the best choice as a daily commuter. Since I needed another more reasonable car for commuting anyway a used 2014 Leaf came up for me as a viable option to commute cheaply to work within the budget I had already set for this purpose. The next level would be when the roof next needs a re-do to consider solar hot water and electric with a subsidiary and use that to defray the cost of replacing the roof since it will need to be re-done in part during the conversion anyway.
When I suffered a crippling disability from a ladder accident I had to move from New England to an area with a more stable barometric pressure. San Diego California was one of the candidates however utility rates were too high there so I passed and chose a location where the utility rates and taxes were more reasonable.
Yes there may be a few areas in the country where due to insane electric rates you may break even on electrical savings on an L2 over an L1 in about a decade but even that is not good enough on its own to justify the costs.
Its still mostly a convenience upgrade unless you live in an area where the utility company or State basically installs the L2 for free or pretty close to it. Then of course it makes perfect economic sense. Where I live the rates are so low that they do not provide free L2 chargers however a bit South of here the rates are a tad higher and the power company does basically give away the L2 chargers and subsidize their installation if the person telling me this is correct.
TimLee
Well-known member
OT, but not sure that is necessarily correct for Tampa Bay.RockyNv said:
If you have enough passive solar and do no heating it could be correct.
But there has been huge improvements in efficiency with the mini split heat pump units in past 15 to 20 years (Been available in Japan and Europe for 30 plus years.)
Some of those aren't a lot more than central AC only.
And you get markedly better humidity control plus heat in winter.
TimLee said:
Yes OT a bit but I use heat maybe 5 days a year and so the added cost of the Heat Pump and general loss of efficiency on AC makes it an unwise investment compared to the likes of a 19.5 seer Trane with dual compressors mated to the variable speed air handler with its dehumidification cycles. Even if the efficiency ratings were equal the added cost of the Heat Pump for those very few days or most years just hours of running the heat to take the chill off during the morning shower cycle is not worth the extra expense. Just like the Leaf purchase it had to have a certain cost benefit related to it. A heat pump for the house for me was a loose/loose proposition with 0 benefit at the time I purchase my system especially since the more expensive Heat Pumps were only 15 to 16.5 seer at that time.
TimLee
Well-known member
Agreed with those #s.RockyNv said:
But the #s are changing a lot.
I put in a Mitsubishi mini split three unit system for my mother-in-law's basement apartment.
Markedly higher SEER.
Pleased but still probably should have put in outdoor air makeup unit.
I'm in ASHRAE.
Amazing how imcompetent the standards were until the last ten years.
In the southeast the key is make the house air tight and provide makeup air system that removes the incoming humidity from the incoming air that you need for good air quality.
Most of the AC load is latent heat (humidity removal).
Don't do that and you build cold but miserable mold infested buildings.
Durandal
Well-known member
cwerdna said:
Man, if I was paying $0.399/kWh for electricity, I would have gone 100% solar already. Fortunately electricity is extremely cheap here for residential use, roughly $0.10/kWh for me, but I charge at a spot nearby work that is free, being sure to move my car as soon as it's charged up.
I've been pondering setting up an independent semi-offgrid system, where most of my 120v usage comes from solar, and then using the mains power for 240v and for topping up the batteries if the solar panels aren't keeping up. I would prefer this to net-metering, to provide for off-grid power in case of grid failure power outages.
RegGuheert
Well-known member
The average Nissan LEAF is driven nearly 10,000 miles/year, not 5,000 to 6,000 (but also not 12,000).RockyNv said:
cwerdna
Well-known member
Sigh... I just checked https://www.pge.com/tariffs/tm2/pdf/ELEC_SCHEDS_E-1.pdf again and now our new tier 3 (every kWh beyond 606 kWh in a 30 day month) is 40.307 cents/kWh!Durandal said:
The baselines are unchanged.
Per the current E-1 schedule and my area and baseline, 900 kWh would cost ~$247 here, likely not including any additional taxes and fees.RockyNv said:
The only saving grace is that in April and October, every household gets a $28.14 "California Climate Credit" on their bill.
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