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Comment Re:Tesla (Score 4, Interesting) 327

And that's your excuse? I drive electric too, some 25Mm (16kmiles) per year, but my family is in the "net negative" camp. Solar panels on 1/3 of my roof more than cover for all my driving, plus everything else in the house.
With a 16k$ investment, I went from spending 3k$ per year on fuel and electricity, to zero.
Destroying this planet a bit less feels great too; who knows, my kids might want to live there...

Comment Re:Depends on the energy source duh! (Score 4, Insightful) 775

Comment Re:do it right (Score 1) 198

Li-ion in general, and variants currently used for EVs (e.g. NMC) in particular, dramatically outperforms lead-acid:
- 3 to 5x the energy density
- 5 to 20x higher sustained discharge current
- 10 to 20x faster charge
- 2 to 10x cycle life
- higher charging efficiency, lower self-discharge, longer calendar life so less maintenance, etc. And all those figures keep improving, albeit slowly.

EV battery packs are expected to be retired when they reach 70 to 50% capacity. As Li-ion's capacity fade slows down with age (assuming constant depth of discharge cycling; ie you lose less capacity the 2nd year than the first, less the 3rd than the 2nd, etc), a "spent" automotive pack may well have 2/3 of its life still remaining.
All will boil down to pricing, but from technical specs only, used EV batteries look much more interesting than lead-acid for grid-helping applications.

Comment Re:I'd do it tomorrow (Score 3, Insightful) 237

Germany leads in solar mostly because it's quick, easy, and therefore cheap, to get solar projects approved there. It's a nightmare in the US, at least the city where I live; I've been going through this for months: already dozens of pages of blueprints, specifications, calculations etc filed, thousands spent, and still no end in sight.

Comment Re:Two plugs in one? (Score 1) 212

Er, no, you're making things up here. The SAE only claims that the receptable on the car can be made to accept existing J1772 connectors, not the other way around. On all recent plug-ins and EVs I've seen, only the Nissan Leaf (ironically enough) might have enough clearance around its J1772 receptacle to accept this new proposed plug. Chevy Volt, Mitsubishi i-MiEV, Prius plug-in, Ford focus... forget it.
(and to clarify, the charger all those have on-board is single-phase AC, not "2-phase")

Regarding the reality of DC fast-charging: first, it's here today (despite the SAE, not because of it) and it works very well. And yes, cables are thick and heavy, but certainly not more than a gas pump tube and nozzle.

Multiple automakers (Nissan, Mitsubishi, Subaru, Peugeot..) and charging equipment vendors (Eaton, Fuji, AeroViromnent, Efacec, Andromeda etc etc) already implemented another, existing standard, CHAdeMO, starting years ago. (none of them use capacitor banks btw, just a regular commercial electrical circuit).
The batteries in tens of thousands of EVs already on the road handle fast-charging just fine, thank you. Not just at fast-charging stations but also every time the vehicle slows down btw (regenerative braking happily pumps tens of kW back into the battery).

Second: unlike you I think that DC fast charging is critically important for wider EV adoption.

The two biggest hurdles for EVs today in the market are initial cost and limited range.
Batteries will remain pricey for the foreseeable future, so cheaper EVs will continue to come with relatively modest packs (say 16 to 30kW*h), and therefore only 50 to 120 miles range. Extending this range by recharging is only practical if it's quick enough, ie counted in minutes and not hours like with traditional AC charging stations -- I really don't mind stopping 15~30 minutes on an occasional 150 miles trip, in exchange for that lifetime 80%+ discount on "gas", and I could see such compromise being totally acceptable to a lot of people.
Now those 50kW+ chargers are big heavy expensive beasts, so keeping them outside the car (hence DC at the connector), usable by more than one vehicle, makes complete sense.

So yep, DC fast-charging is a very practical and cost-effective way to lift the range constraints otherwise inherent to more affordable EVs.

Freedom and $$ -- you were calling this 'irrelevant to most'?

Comment Re:Another one? (Score 1) 212

So you can have a relatively low-cost, slow charger at home. Charging stations can provide a fast DC charge.

This is the whole idea, it makes tons of sense and is exactly where manufacturers are headed... oh wait, Nissan, Mitsubishi, Subaru, Peugeot etc are already there!

Maybe this SAE re-announcement is only meant to muddy the waters about DC fast charging, in the hope to slow down its much-needed deployment in the US and possibly elsewhere, reducing the usefulness and therefore attractiveness of pure EVs... To please some existing industry(ies)? To help non-Japanese automakers catch up? [insert your own conspiration theories here]

Unless Nissan comes up with a surprise with its 2013 Leaf (2011 and 2012 use CHAdeMO), or Tesla Motors jumps ship, this SAE proposal doesn't seem in good shape...

Comment Re:Strict Emissions Standards Benefits Electric Ca (Score 2) 191

The vast majority of EV charging occurs between midnight and 4am, when there is ample capacity, esp from wind, so EVs actually use the cleanest part of the grid.
Which in California is quite clean to start with: most of its electricity is coming from carbon-neutral sources (hydro, nuclear, geothermal, wind...); only 7% was coal in 2010 and getting lower.

Another sobering thought: the energy spent refining gasoline alone (6kW*h / gallon) for a 20-some mpg vehicle would be enough to propel an EV the same distance.

Comment Re:Captain Obvious (Score 1) 341

For a true apples-to-apples comparison, we should include the considerable CO2 emissions that come with refining and shipping petrol.

In the US, according to the DOE, refining 1 gallon of gas uses about 6 kW*h. This is enough to propel your typical EV (e.g. Nissan Leaf or Mitsubishi i-MiEV) some 30+ km (20 mi), significantly more if you hypermile.
So there you have it: an efficient EV can travel the same distance as a gas-guzzler on just the energy needed to refine gasoline.

Comment Re:Largely Demand Driven (Score 1) 490

[plug-in hybrids] will provide enough incentive for a cjharging infrastructure to grow up. And as it does so, the opportunities for electric only vehicles expands.

Sadly, no. First, except to the owners of such vehicles, I actually don't see much incentive to install charging stations for cars which can do just fine without. There is little to no money to be made directly: plug-in drivers won't pay to charge unless it's cheaper than gas, leaving $2/h margin; this may not even pay for installation, maintenance, insurance...
Second and most importantly, to effectively extend the range of a pure EV, charging needs to be an order of magnitude faster than what plug-in hybrids support.

Standard, aka slow, charging (level 2, 10~20 miles of electric range per hour), like is being used for plug-in hybrids, is only useful for pure EVs at locations where people are expected to stay for extended periods (home, work, hotel...). Their deployment elsewhere actually distracts from, and may prevent, the installation of much faster chargers (level 3, 150+ miles per hour), which plug-ins can't use and don't really need anyway, but which EVs absolutely require to 'refuel' in a tolerable amount of time.
[Given the drastically different power requirements, the wiring etc installed for level-2 stations can't be reused for a level-3, so it's not like those can easily be upgraded later either]

Comment Re:Competitive does not require equal - Exactly (Score 1) 490

You are spot on.
My only car is an EV, a Nissan LEAF (and I love it btw), which can be fast-charged. On average it actually takes me *less* time to juice it up than fill-ups for my previous 28mpg vehicle.

98% of the time, as I charge at home, it only takes me seconds to fill up: open the charging bay, plug in -- done.
Sometimes I stop at a station like . The LEAF's quick-charge port (CHAdeMO) gobbles up to 125A at about 400V DC (50kW).
This fills up half the battery, or 30 to 50 miles of range, in just over 12 minutes. While I certainly wouldn't want to do this daily, I find this perfect to occasionally extend the range as needed. The battery capacity is no longer the limit.

Of course everyone's situation is different, but for me (12~15k/y), the combination of home charging and quick-charging as it exists today is not just merely practical, it's already better than gas. And it doesn't even need to be to be successful.
I routinely saw cars in line at cheap gas-stations (Costco), people ok waiting 5+ minutes for what's maybe a 10% discount. Now imagine 80%...

The only real problem is that those EV quick-charging stations are still rare to non-existent in most areas, and IMHO, understandably, unless/until this changes, EVs will remain too range-constrained (and/or too pricey, extra batteries are $$) for most people to make the switch.

Comment Brilliant, a yet-different American-only "standard (Score 5, Interesting) 373

And predictably, the only 2 major players in the EV market now, Nissan and Mitsubishi, will just stick to the only widely-deployed fast-charge connector to date, CHAdeMO

By announcing this new American-only Frankenplug, the SAE only helps delaying the (IMHO much-needed) EV adoption in the US and related charging infrastructure. But that's probably exactly what Chrysler & Co want, so they have more time catching up with the Japanese automakers...

Comment Re:I take it (Score 1) 402

I can't comment on other EVs but at least on the Nissan Leaf, that subtle "something mechanical" sound you may hear when such vehicle move at very low, parking-lot speeds... well, it's not from the motor, inaudible when developing virtually no power, but from a small audio speaker. A very good feature if you ask me.

Good background info etc@

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