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GAS PRICES....WTH :angry:

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MonMotha:

--- Quote from: ChadTower on March 08, 2011, 10:44:47 am ---
I'd like to know how we could expect an aging and already insufficient power grid to take on the added load of charging automobiles.  Places like California have had to resort to rolling blackouts for a long time now.  Places with seasonal demand for home air conditioning (like New England) are starting to have issues all summer.  What is going to happen to the grid when people start plugging cars in to charge overnight?  Cities and states don't want to spend the money to ramp up the grid because it is invisible capital expense but if they don't get on this soon all these plug in electrics are nothing more than a pipe dream.

What happens when we have a power outage?  Your internet and VOIP phone are dead as are your refrigerators and possibly heat/cooking.  You have limited time on your cell phone.  Now we're talking about being unable to drive because we can't charge the car?  Are we going to start keeping gas tanks on site specifically for backup generators to charge the cars we no longer want running on gas?

--- End quote ---

The grid in the USA could handle a reasonable number of people charging their electric cars at night.  Electricity discounts during off hours are available to residential customers in many regions already and have been standard (and even required) for commercial customers for years, so you could take advantage of this, and it would naturally encourage people to charge their cars at night, which they'd probably largely do anyway, when there is excess capacity available.

The grid is already a little strained in the day especially during peak heating and cooling seasons; this is a known problem.  It will need upgrades no matter what, and programs to do so are in place.  There are also some nifty ideas being floated around about using the battery capacity in electric vehicles (since it's actually pretty huge) to offset peak (and I mean PEAK - like for less than an hour during the day) electricity demand.  And before someone runs off on a tirade about how that means your car may not be fully charged, participation would be optional and encouraged via compensation, and the amount of draw-down on the batteries we're talking is only a few percent.  It's enough to make a huge difference when you've got several hundred thousand cars to do it with, but it's so little that you'd barely notice.

As for what to do when the power is out, well, you should have at least 100 miles on a charge (that's CURRENT vehicles - it's only going to go up).  I get 350-400 on a gas tank, but I'm not likely to fill it up every evening like I would be apt to plug my car in since filling up a gas tank requires a trip to the gas station while I can plug my car in to charge at home.  If I had to guess, I'd say I average about 200-250 miles "reserve" on my tank at any moment and that's only because I rarely let it get below 1/3 full; I know many many people who don't fill up until the light comes on, so their numbers would be lower.  Given that the gas station's pumps are unlikely to work in a city wide power outage, I'm not sure that's something worth throwing a fuss over.

Electrics aren't great for everyone.  If you routinely drive more than ~75 miles in one trip where you would be unable to charge, they're probably not a good option for you right now.  I realize this describes a good chunk of the population.  The other chunk is also quite sizable.  There's a reason we already have several types of vehicles (small cars, vans, light trucks, big trucks, busses, etc.).  Electric passenger cars just augment the selection.


And yes, heat engines (especially those running an otto cycle i.e. gasoline engines) are generally woefully inefficient.  The saving grace is that gasoline is cheap and extremely energy dense, so you can waste a lot of its energy as heat and still get a lot of useful energy i.e. propulsion.  Diesel cycles are a bit better.

The cycle that is run in a heat driven power plant (coal, solar thermal, nuclear, some natural gas) can be a bit better (look up a rankine cycle).  The real gains are caused by economies of scale, especially in the waste product (e.g. environmentally hazardous gasses): it's practical to put some amazing pollution controls on a commercial scale power plant, but economically impractical to do so on a car.

Electric cars also enable you to decouple the generation medium from the vehicle.  That is, you can have a "nuclear powered car".  Obviously nobody would ever put a nuclear reactor on a car, but nonetheless you can have most of the benefits of a nuclear power plant when it comes to powering your car.  Right now, petroleum fuels are so cheap in the USA that this isn't a huge deal, but if the cost of oil keeps going up, it could become quite nice.  Coal is plentiful, available in the USA, and cheap (if environmentally questionable).

Once the electricity is produced, the distribution and battery storage is reasonably efficient all the way to the motor of e.g. a car.  Typical losses in battery charging/discharging, conversion, and motor heat loss should add up to around 25-30%, assuming a reasonably efficient motor and VFD, giving you an efficiency of ~70-75% excluding grid transmission losses which will vary heavily with where you are and grid load.  These losses have been trending down for the past 20-30 years.  I remember designing SMPSes just ~10 years ago and having literature tell me that 70% efficiency was good.  Now, if I'm not hitting 85%+ at design load, I'm a little unhappy if there isn't some oddball factor causing it.


--- Quote from: Mikezilla on March 09, 2011, 11:37:53 am ---
--- Quote ---Oh, and those of you in the states? relax, price of gas there is still heaps less than most other places in the world. I just noticed today that 98 octane here in Brisbane, Australia is $1.65 a litre. That's $6.27 a gallon...
--- End quote ---

Am I reading this right? 98 octane!? The highest octane rating you can get here in CA is 91. I think they only sell 98 octane at racing places.

--- End quote ---
Europeans use a different system of measuring the "octane" rating of gasoline than we use here in the states.  There are two established methods.  One gives a higher number (RON) than the other (MON).  In the states, we average the two results: the (R+M)/2 method you see referenced on labels.  The Europeans use the higher number only.  98 octane in Europe should be about like 93 in the states, which I can get at any quality gas station in the Midwest.  CA numbers are sometimes lower due to pollution control additives.

Mikezilla:
Thanks for the interesting read MonMotha. Ah, ok cool, that makes sense. Yeah, they got rid of 93 octane here in CA around 2001 due to the air standards. The most we can get at a regular gas station is 91. They have specialty stations in hickey places that do a lot of racing etc. At least in San Diego.

ChadTower:

--- Quote from: MonMotha on March 09, 2011, 12:04:51 pm ---The grid in the USA could handle a reasonable number of people charging their electric cars at night.
--- End quote ---

The local grids are not up to this.  Not here, anyway, and not in an awful lot of places.  The weather this winter also made it abundantly clear how easy it is to end up with outages lasting several days.  A developer has been trying to build an office park by my house for years but can't because the grid cannot handle the load he would require.  The local grid is old and the load has outgrown its original design by a large margin.  Note that we have the same issues with central sewer and water.  We are actually at a point now where expansion of any type just can't happen until capacity increases and the utility companies are holding the state gov't hostage until they cough up chunks of subsidy that elected officials aren't going to provide.



--- Quote ---Electricity discounts during off hours are available to residential customers in many regions already and have been standard (and even required) for commercial customers for years, so you could take advantage of this, and it would naturally encourage people to charge their cars at night, which they'd probably largely do anyway, when there is excess capacity available.
--- End quote ---

Once people start plugging in their cars at night there won't be excess capacity.  No excess, no discount.  I would be surprised if that didn't become premium time using the same lever that gas stations use.  You have to get to work regardless of fuel cost.



--- Quote ---The grid is already a little strained in the day especially during peak heating and cooling seasons; this is a known problem.  It will need upgrades no matter what, and programs to do so are in place.  There are also some nifty ideas being floated around about using the battery capacity in electric vehicles (since it's actually pretty huge) to offset peak (and I mean PEAK - like for less than an hour during the day) electricity demand.  And before someone runs off on a tirade about how that means your car may not be fully charged, participation would be optional and encouraged via compensation, and the amount of draw-down on the batteries we're talking is only a few percent.  It's enough to make a huge difference when you've got several hundred thousand cars to do it with, but it's so little that you'd barely notice.
--- End quote ---

I can't see people doing this without solid demonstrable evidence that it would not reduce the lifespan of their battery array.  Or at least a design where parts of the array are replaceable in a reasonably affordable way.  Right now the batteries are so expensive people talk about replacing the whole vehicle when the battery is shot.



--- Quote ---As for what to do when the power is out, well, you should have at least 100 miles on a charge (that's CURRENT vehicles - it's only going to go up)..

--- End quote ---

It's also the figure for a full charge.  How many people keep their gas tank 100% full all the time?  Granted, that practice might change when you can refuel in your own driveway, but people are stupid.  It might not.

MonMotha:

--- Quote from: ChadTower on March 09, 2011, 01:11:42 pm ---
--- Quote from: MonMotha on March 09, 2011, 12:04:51 pm ---The grid in the USA could handle a reasonable number of people charging their electric cars at night.
--- End quote ---

The local grids are not up to this.  Not here, anyway, and not in an awful lot of places.  The weather this winter also made it abundantly clear how easy it is to end up with outages lasting several days.  A developer has been trying to build an office park by my house for years but can't because the grid cannot handle the load he would require.  The local grid is old and the load has outgrown its original design by a large margin.  Note that we have the same issues with central sewer and water.  We are actually at a point now where expansion of any type just can't happen until capacity increases and the utility companies are holding the state gov't hostage until they cough up chunks of subsidy that elected officials aren't going to provide.

--- End quote ---

Sounds like your city has crumbling infrastructure.  That's common, but by no means always the case.


--- Quote from: ChadTower on March 09, 2011, 01:11:42 pm ---
--- Quote ---Electricity discounts during off hours are available to residential customers in many regions already and have been standard (and even required) for commercial customers for years, so you could take advantage of this, and it would naturally encourage people to charge their cars at night, which they'd probably largely do anyway, when there is excess capacity available.
--- End quote ---

Once people start plugging in their cars at night there won't be excess capacity.  No excess, no discount.  I would be surprised if that didn't become premium time using the same lever that gas stations use.  You have to get to work regardless of fuel cost.

--- End quote ---
It is possible that some of the discount may go away.  Smoothing out the load is a good thing from an overall efficiency standpoint, though.  I suspect most people would tend to charge their cars at night whether there's a discount or not.  Subsidies (which have been discussed) may enable the discount to continue even if it doesn't economically make sense simply to keep the load smooth like this.


--- Quote from: ChadTower on March 09, 2011, 01:11:42 pm ---
--- Quote ---The grid is already a little strained in the day especially during peak heating and cooling seasons; this is a known problem.  It will need upgrades no matter what, and programs to do so are in place.  There are also some nifty ideas being floated around about using the battery capacity in electric vehicles (since it's actually pretty huge) to offset peak (and I mean PEAK - like for less than an hour during the day) electricity demand.  And before someone runs off on a tirade about how that means your car may not be fully charged, participation would be optional and encouraged via compensation, and the amount of draw-down on the batteries we're talking is only a few percent.  It's enough to make a huge difference when you've got several hundred thousand cars to do it with, but it's so little that you'd barely notice.
--- End quote ---

I can't see people doing this without solid demonstrable evidence that it would not reduce the lifespan of their battery array.  Or at least a design where parts of the array are replaceable in a reasonably affordable way.  Right now the batteries are so expensive people talk about replacing the whole vehicle when the battery is shot.

--- End quote ---
Hence why it's optional.  I can't imagine you'll ever be required to participate.  You can always just buy electricity "for general use" like you do now.  Of course, the discounts may be substantial enough to offset the potential battery replacement costs, especially if you only keep your car ~3 years like the average American.

How much it will impact the life of your batteries depends on the battery tech.  For the Ni-MH batteries used by Toyota, it's certainly something to consider.  They don't like being partially cycled.  They're not nearly as bad as the old Ni-Cd chemistries, but they still don't like shallow cycles.

For Lithium chemistries, it varies.  Traditional Lithium Cobalt chemistries, which I believe the Volt and Leaf are using, don't really mind being cycled much.  They don't like being fully depleted, stored at high temperatures, or charged below freezing.  IIRC, both the Volt and Leaf include a heater (powered by the charger) to warm the battery pack for charging when the outside temp is below freezing.  Deterioration of Lithium Cobalt batteries tends to be related more to time and temperature than any usage patterns, assuming the charger used is good (which it isn't on a lot of consumer electronics - I don't know how good it is on the Volt or Leaf).  I agree that I'd like to see some details on how well the charger treats the battery to know that it won't do much long term harm, but again, it depends on how deep the electricity discount goes.

Newer Lithium chemistries not yet in high volume production make some trade-offs in energy density (so you need more batteries to get the same capacity) in exchange for longevity and power handling (how fast you can charge and discharge them).  This is a decent trade off for vehicles, especially non-tiny ones.  These will likely see used in potential future electric light trucks (e.g. SUVs) and busses.  Railroads are also very interested in these.  Altair Nano has made some rumblings about 20 years to 50% ("traditional" Li-Ion Cobalt chemistries are 3-5 years to 50% but this has improved over the past 5 or so years) and virtually unlimited power handling with the only real downside being approximately half the energy density of a typical laptop battery (which are engineered to be extremely energy dense at the expense of longevity).  The latter advantage of high power handling is cool because it means that, with a sufficiently large motor, you can have killer acceleration, very efficient regenerative braking, and, with a sufficiently large electric hookup, essentially full charges in about the time it takes to fill a typical gas tank.  Low volume production is ramping up.  I'd expect to see volume sufficient for automotive use within 5 years.  I believe they are calling these "Lithium Titanate" chemistries.  See also "Lithium Air" chemistries.


--- Quote from: ChadTower on March 09, 2011, 01:11:42 pm ---
--- Quote ---As for what to do when the power is out, well, you should have at least 100 miles on a charge (that's CURRENT vehicles - it's only going to go up)..

--- End quote ---

It's also the figure for a full charge.  How many people keep their gas tank 100% full all the time?  Granted, that practice might change when you can refuel in your own driveway, but people are stupid.  It might not.

--- End quote ---

I guess.  It seems so convenient that I'd figure most people would pull up and plug their car in as part of their typical "park" routine.  The relatively lower "capacity" would seem to encourage this, though I wouldn't otherwise say it's a positive.  Nissan is supposedly offering an extended battery pack to ~200miles typical as an option on the Leaf, but it's quite expensive, and I would guess it takes up part of e.g. the trunk.

It seems that having half to a third the available range in a dire emergency (whole city without power; I think you'd have other concerns) is an acceptable tradeoff for approx 1/3 to 1/5th the energy costs (which is what it'll generally work out to at current gas and electricity prices; YMMV with region especially as areas like CA have very expensive electricity).

If you're one of those people who has to have a 4 ton pickup with 600 mile range just in case the zombie apocalypse happens tomorrow with no warning and want to have no other vehicles, I'd guess that an electric car isn't for you right now.  I probably wouldn't keep one as my sole vehicle, but I'd imagine that if someone were to give me a Leaf or Volt right now, I'd use it about 80% of the time (my sole vehicle right now is a mid-size, gas powered sedan), but I'm not planning on purchasing one as the up-front cost is still a bit high for me to justify.  There's always the rental option if you do need a giant vehicle for a weekend or something.  Probably cheaper than owning/leasing one full time if you only need it a few times a year.

ChadTower:

I could definitely see things like Zip Cars going full electric.  I see them all the time near my house and they are just about the right size.

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