fooljoe said:
muus said:
All this talk of low power "quick" chargers is quite discouraging. To me, a charger that takes more than 30 minutes is not a quick charger. A 20kW "quick" charger is equivalent to an 80A L2 EVSE, only the current generation of EVs aren't able to take advantage of them (other than Tesla).
I agree. While it would be great to have a plethora of Chademo options available, if I were going to invest in one I would definitely want the maximum power output possible. What I take from this discussion is the need to couple EV quick charging with some kind of load-leveling energy storage. This is actually not a new problem at all - there are many areas now where a large surge of power is needed without causing a brown-out on the local grid or entailing huge demand charges. Labs that test circuit breakers are one example, or even
roller coasters that start out with a quick burst of speed. Using a battery bank to achieve this has been discussed here, but actually you're more likely to find
flywheels in use with these current applications.
Please invest away, purchase, pay installation and operational costs for all those maximum power output Quick Chargers, and purchase the load leveling equipment and flywheels to go along with it. We'll all be happy to use your money. Let us know if you have a business plan that is sustainable with revenue coming in that exceeds the operational and cost of capital costs.... If you have something that works, share the secret, assuming you want more quick chargers, and we'll pitch it to host sites and get tens of thousands of Quick Chargers installed with the maximum power output possible! These maximum power output Quick Chargers are possible, but are they ECONOMICALLY possible? Can you make enough revenue to cover capital costs of charger purchase, installation, electrical energy, electrical demand and maintenance costs? Can you make enough revenue to turn a small or medium profit? What are the relative levels of pack degradation for 20, 50, 100, 250 kW Quick Charging?
Tesla has got it right, Sheesh, we paid $700 for the QC port to start with. Going from a 3.3 kW to a 12kW charger could be sold as an option or just rolled into the car price, as additional $1,800 over the current price. I guess at $1,800, it would probably have to be an option. Actually, it's only $1,100 over the cost of the 6.6 kW charger they're putting in the 2014 LEAFs ayway! I'll get a lot more use out of an onboard 12 kW charger than I will out of a Quick Charger, because there will be so many more desirable locations to charge at. Going up to a 20 kW onboard charger would be $3,300, 0r $2,600 more than the 6.6 kW. I'd pay for it, no question! with 240V 70A J1772, dozens of which are already installed and operational!!! - I could do San Jose to Monterey round trip with two charge stops and charging at the aquarium.
An investment to a certain level of 12 to 20 kW of onboard charger is going to be for many people more cost effective than purchasing a larger battery pack, or paying for Quick Chargers and the resulting battery degradation. We still need Quick Chargers, but they pose tradeoffs of high costs and battery degradation and they stop Quick Charge speed at 80%..
We also need 240V 70A J1772, because when we get to 200 and 300 mile battery packs, 240V 30A is going to be like 120V charging compared to the capacity of these packs that we will be getting in EVs (not the LEAF intially, maybe later...). And we need Quick Chargers also for these larger packs.
With the whimp 3.3 kW onboard charger, even with a QC on route, I'd need another QC at the aquarium, because If I spend 4 hours in Monterey, the 3.3 kW has only returned a bit over 50% charge, while a 6.6 kW would be 95%+.
With the 3.3 kW I'd need 3 QC stops in a day, shortening pack life. With an onboard 12 kW, I'd only need 20 minutes to pick up the 15 miles I need to bridge the trip in each direction - and I could AVOID any pack life degradation from a Quick Charger! I'd have several sopts to choose where to charge, since for each Quick Charge location there can be dozens or hundreds of J1772 240V 70A (Actually, 60A is enough for 12 kW, even at the common 208V supply).
Quick Charge is a great complement to the charging options we need to maximize the utility of our EVs.
We need the full spectrum from 120V when we only need a little charge of have a long time (airports for a trip, etc.) to charge, 240V 30A for when we need 20-50% charge and are spending a couple hours doing something else, 12 kW 240V for when we need 10 - 50% charge and we are WAITING for the charge - want to extend our battery life - or someone else is already using the only Quick Charger at the site! And Quick Chargers for those trips when we need 80% boost ups - but the problem is it only goes to 80% and multiple quick charges during the day is going to shorten battery life more.
I'd like to use QC for two boost ups on trips that are 200 miles each way, but the impact ot battery life has to be weighed. I haven't heard any data on the relative level of battery degradation of a 20 kW vs. 50 kW vs. 100 kW vs. 250 kW quick charging. Quick Charging has costs - not just in terms of the cost of the Quick Charge but also the lasting costs of battery degradation to your vehicle causing you range to decrease a little faster over the years.