Skullbearer said:
Ok, a simple case for doing 6.6/7.2kW charging or quicker is to install a dedicated 'on-board' charger at your home and utilize a communication gateway to translate from the GreenPHY and J1772 standards on the pilot pin to the CAN or analog communication expected by the stand alone charger. In this manner we can design a hybrid Charger/EVSE station at decently low cost for home or business use using the so called 'Frankenplug' or as I'll refer to it, the SAE J1772 CCS.
The CCS allows simultaneous 1 phase, split phase, or 3 phase AND/OR DC charging with the combined J1772 and GreenPHY J1901 based communication for control. I need to dig into the J1901 standard to see how reproducible it is. An ElCon charger for example, combined with the CCS could be used to provide up to 3.3kW via the existing Spark charger plus 3.6 or 7.2kW via the DC ports.
What's everyone think about that? Your looking at a standard EVSE setup for at least 30A of charging (40A breaker) plus the charger... around $1,500-$2,000 with parts at a small resale profit. Maybe I might be able to spare the time for doing the design by the end of summer, 2014. The system could be portable, but that would be a big heavy thing to lug around, so mostly a dedicated station. Could be made so that you plug your J1772 EVSE into a port on the 'boost' unit (ie the charger), then plug its CCS into the car, which would keep the two units separate and modular.
Maybe we should start discussing price points here. How much is 4 hour charge from 0 worth to you Spark EV owners? I can work with MetricMind or do something separate, however there is no getting around a $750+ cost for a reliable 3.3kW charger at reseller costs, plus you need to add in some margin. Let's rank it like this:
-6.6kW J1772 (Fully on-board) Charging is worth $XXXX to me if I install it from a kit, and $YYYY to me professionally installed.
-6.6kW J1772 CCS (3.3kW on-board, 3.3kW DC off-board) Charging is worth....
-9.9kW J1772 CCS (3.3kW on-board, 6.6kW DC off-board) Charging is worth....
Give realistic pricing here, assuming a 3 year warranty and no decrease in the life of your Spark EV on board equipment. After sufficient feedback I'll look into it more.
I think you're really onto something here....
This has a lot of potential as the basis for residential L3 charging. I think it would really only be practical with the CCS plug too. I'm not sure you could license the plugs or protocols from Tesla or CHAdeMO very easily. Also, with both your costs would go up dramatically because you couldn't use the OBC to speed up charging.
Since the Americans and Europeans are supporting CCS you should really be thinking about a broader market than just the Spark. The i3 uses the rare 32 amp J1772. People that want the most out of their vehicle will probably spring for the more expensive home charger and the higher quote from the electrician for installation. When they find out that their car was designed with a DC socket that will eventually be useful at DC-FC stations that might exist near them someday, they will be apathetic. When they find out that their car was designed with a DC socket that can work with a home charger that cuts the charging time in half because it uses the OBC and a garage installed DC charger at the same time, range anxiety will start to melt away.
Price isn't as important as you might think when realistically this is a green replacement for a range extending gas motor. At over 10kW of total charging capacity, stopping at home for 20-minutes in between errands is enough to add a significant amount of range.
Realistically, you wouldn't have to stop at 6.6kW of DC-FC capacity either. You're only limited by how many amps there main service box can draw, and how much power they can get permitted for. Someone in the i3 demographic could easily have a $5,000 budget if the change was significant enough. You shouldn't be afraid of a healthy margin on a top shelf model.
Upgrading the OBC on the Spark will probably never make you money for a few reasons. The Spark EV is more of an appliance car than some of the competition that let price run away with them. There are lots of reasons to love the Spark EV, but a strong percentage of owners are very price conscious. You probably couldn't sell an upgrade kit for the OBC for less than $1,500, and it would cost at least $2,000 installed. GM is bound to come out with a 6.6kW OBC eventually and your market would shrink to the owners of used Sparks that are even more price conscious. The modification would also have to be depreciated in the resale process too.
Residential L3 chargers could also have a lot more appeal for committed EV buyers that know they will buy another EV. You also might get some business owners interested too. Even if it isn't an 80% recharge in 20 minutes, your charger could easily undercut the $25K-$50K that most DC-FCs cost at present.
To speculate with you about the value of a Residential L3 charger, I would say that 6.6kW of off-board charging is worth:
$4,000-$5,000 to someone that will use it daily.
$2,500-$3,000 to someone that will use it weekly.
$1,500-$2,000 to someone that will use it monthly.
$1,000-$1,500 to someone that just thinks it's cool and really only uses it to show their friends.
I wouldn't try to sell a 3.3kW off-board charger for more than $1,500.
I think 3.3kW off-board charging would be much less appealing. It's just not dramatic enough of an improvement for only working at home. 6.6kW charging is dramatically more useful when you're out of the house because you rarely are going to be there long enough to make a difference. 10-13kW charging is useful enough to work stopping by your house into your plan.