EcoModder Forum How much are you paying per kwh where you live?

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 04-04-2009, 10:23 PM #11 (permalink) EcoModding Apprentice   Join Date: Mar 2009 Location: Birmingham, AL Posts: 113 Thanks: 0 Thanked 2 Times in 2 Posts that doesn't sound right at all for charge times. I know the aptera (for purpose of this conversation) recharges off 110v but they estimate an 8hr re-charge time from 20%-100%. Jumping it up to 220v should bring it closer to 4hrs am I off here? Does it have to do with amperage and not the voltage? Will I need to wait to purchase a vehicle to determine what type of power (110 vs 220) to have installed? Can I install 220v and use it still even if my EV charges on 110v?
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 04-04-2009, 10:55 PM #12 (permalink) Master EcoModder   Join Date: Nov 2008 Location: Cookeville, TN Posts: 850 Thanks: 1 Thanked 5 Times in 5 Posts Yeah sounds like it charges at fewer milli-amps than 30, thats what guessing gets you. The second part depends. If the charge unit you are buying allows for step-down(allows you to choose 220 or 110) then obviously you can use either for the outlet itself, but definitly do not plug it up at 220 if its supposed to be 110. Theoretically it will charge twice as fast, but in reality it will just burn the batteries charging them too fast. the only two laws you need to know are V=IR, Voltage = Current *resistance, and P=IV, power=voltage*Current. The first if you double the voltage at the same resistance the current doubles. alot of the time thats not a terrible problem because its for a very short period and systems allow for the increased voltage through Zener diodes that limit the voltage to X(sort of what ever you want) so it can take the fluctuation. However when you are talking 110 volts not millivolts to 220 volts I am pretty hesitant to say the system can handle that for extended periods(more than a few minutes). The second is how you determine charge rate. 10KW= voltage*current, 10,000/220= current in amps. So at 50 amps and 220volts it charges in one second.
 04-05-2009, 02:15 AM #13 (permalink) Master EcoModder     Join Date: Jan 2008 Location: Western Wisconsin Posts: 3,903 honda cb125 - '74 Honda CB 125 S1 90 day: 79.71 mpg (US) green wedge - '81 Commuter Vehicles Inc. Commuti-Car Blue VX - '93 Honda Civic VX Thanks: 867 Thanked 433 Times in 353 Posts to charge your possible electric car you need to know the charge rate of the batteries, 6-8 hours is common with alot of EV's, 1 hour to 80% full for quality lithium is pretty fast/good, but for the most part the faster you charge the hotter the battery gets and the sooner the ill need to buy another \$6,000 lithium battery, it's all based off he charge rate, lead acid is often 10% or less of the capacity in amps/amp hours, so my 220 amp hour battery shouldn't be charged at more then 20 amps, and the normal charge rate is closer to 4 amps or 500 watts, that is with a normal on board charger, a 15 amp outlet can handle 1,500 watts safely without starting your house on fire, but really, you don't want to cook the battery, that is why my cordless tools with it's 15 minute charger has a fan that cools the battery, it's a little battery and has alot of air flow to keep it cool. Last edited by Ryland; 04-05-2009 at 03:36 PM..
 04-05-2009, 01:41 PM #14 (permalink) PaleMelanesian's Disciple     Join Date: Dec 2008 Location: Noida, UP, India Posts: 197 City - '04 Honda City iDSI EXi 90 day: 47.47 mpg (US) Thanks: 3 Thanked 3 Times in 2 Posts Guys, I may be wrong, OT and several other unmentionable things, but in the discussion on the battery capacity, the time required to charge it and the energy requirements for a full charge are being treated a bit simplistically here... There is a conversion from the AC mains to some level of DC (depending on the voltage required) required to charge the batteries. Depending on the way this conversion is derived there is a small to substantial energy wastage here. Even a switch mode power supply is really about 80% or so efficient. The battery charging requires charging at prescribed rates to help maintain the battery life, otherwise it would go bad quickly. There are ohmic losses in the battery/batteries, that is not taken into account when the charging energy is quantified. So in general, the total energy required to charge up a 4kWh battery would take much more than 4kWh. To come back to topic, I pay ~\$0.06 to \$0.09 per kWh on my grid electricity bill, which is charged in slabs - first slab is charged less, and if usage increases, the next slab is charged more (assuming the person would not mind paying more as he seems to be rich, based on the energy usage pattern). An additional \$6 flat charge is applicable We also require a backup community DG set for grid power outages (frequent). There is a minimum monthly charge of \$8, adjusted @\$0.17/kWh on the usage from the DG set. So, depending on how much electricity I use (starting with 0 use = \$14 flat charge) I pay ~\$30 to \$60 (in summer, owing to AC use) per month. __________________
 04-05-2009, 02:11 PM #15 (permalink) Master EcoModder   Join Date: Nov 2008 Location: Cookeville, TN Posts: 850 Thanks: 1 Thanked 5 Times in 5 Posts Very true. . .but we don't have the values for these specific batteries or the charger unit and its eta, so we just did with a perfect system. Thats a baseline of what it will always cost at least more than this. Which is a pretty good place to start since everything else is pretty highly variable(what is the temperature outside, is there any wind, did you just finish driving and the components are producing extra heat, has the charger been running for a week or is it brand new, are the wires in the outlet new, is it peak off-peak.) In short there are way too many factors for it to be worthwhile to compute an exact amount. The estimates are reasonably close and to get an approximation thats near exact would take alot of effort.
 04-05-2009, 03:06 PM #16 (permalink) EcoModding Apprentice   Join Date: Mar 2009 Location: Birmingham, AL Posts: 113 Thanks: 0 Thanked 2 Times in 2 Posts great discussion going on in here. I'm paying about \$0.33/kwh at my business just for power. when you tack on all the other assorted fee's it jumps up quite a bit. (I'm paying about 9.2c/kwh at home though so that seems fair)
 04-05-2009, 03:25 PM #17 (permalink) Master EcoModder     Join Date: Jun 2008 Location: Northwest Lower Michigan Posts: 1,006 Red Car - '89 Chevrolet Celebrity CL 4 door Team Chevy 90 day: 36.47 mpg (US) Winter Wagon - '89 Pontiac 6000 LE Wagon 90 day: 28.26 mpg (US) Thanks: 8 Thanked 17 Times in 16 Posts [QUOTE=Electric Frenzy;95785]I'm paying close to \$.33/kwh for my business. Seems like it's only about 3x's higher than everywhere else in the nation. Alabama has a massive problem with Alabama Power. They installed new "instant read' meters which are connected to their grid somehow and give 100% accurate instant readings....yet I can't look up my power usage on the website until the day the bill mails.QUOTE] I'm paying a flat rate of just a sliver under 10c per kwh. Then there is about 10% fees and taxes on top of that. Alabama Power, I cringe when I hear that name. We just built a bunch of bulk material loading equipment for them. I would put them in the top 5 of the worst customers we have had to deal with. It's probably the same company because the ones we dealt with had an office in Birmingham. __________________ Winter daily driver, parked most days right now Summer daily driver
 04-05-2009, 06:23 PM #18 (permalink) EcoModding Apprentice   Join Date: Mar 2009 Location: Birmingham, AL Posts: 113 Thanks: 0 Thanked 2 Times in 2 Posts I'm sure it's the same one. We only have two choices for power in AL and one of them is only north alabama (TVA). Alabama Power is the most hated business in the state. I don't know anyone who has been happy with their service or more precisely their billing. What's REALLY funny is the town my business is in USED to be APCO's headquarters. they've closed up shop and moved to a more bustling part of town now. and of course when the move was announced everyone's rates went up.
 04-05-2009, 10:35 PM #19 (permalink) PaleMelanesian's Disciple     Join Date: Dec 2008 Location: Noida, UP, India Posts: 197 City - '04 Honda City iDSI EXi 90 day: 47.47 mpg (US) Thanks: 3 Thanked 3 Times in 2 Posts Electric Frenzy, is it possible for you to use captive generation of some sorts? Looks like you would be better off with captive generation, if the power co is ripping you so badly... __________________
 04-06-2009, 10:31 AM #20 (permalink) Master EcoModder     Join Date: Jan 2008 Location: Mirabel, QC Posts: 1,672 The Guzzler - '08 Hyundai Elantra GL 90 day: 33.12 mpg (US) Got Soul? - '11 Kia Soul 2U Thanks: 35 Thanked 86 Times in 57 Posts In CAD (divide by .8 for USD) Fixed charge per day 40.64¢ First 30 kWh per day 5.45¢/kWh Remaining energy consumption 7.46¢/kWh The electricity network is government owned here, so it's pretty cheap. __________________ www.HyperKilometreur.com - Quand chaque goutte compte...