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they also have a 30A model for around 200$ more, yeah, they karma can use more then 16Amp (17.8 is what my meter shows) so on a 16A limit it will take 15.8 which is gonna slow you down by around 40 mins if you are charging from 0
 

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The Bosch is discussed in more detail here: http://www.fiskerbuzz.com/forums/24...500-home-level-2-charging-stations-bosch.html

I have the 30Amp (18-foot cord) and have had no problems with it - it looks good and does the job. Harleyguy said I would have done fine (or even better) with the 15 Amp, but it has a 12-foot cord, which would have been tough for me.

If you can get by with the 12' cord (make sure you measure!), I think I'd prefer the lower amperage with a slightly longer charge time - it shouldn't be very significant, but I'll leave comment on that to the electricians and engineers.
 

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Discussion Starter · #4 ·
The Bosch is discussed in more detail here: http://www.fiskerbuzz.com/forums/24...500-home-level-2-charging-stations-bosch.html

I have the 30Amp (18-foot cord) and have had no problems with it - it looks good and does the job. Harleyguy said I would have done fine (or even better) with the 15 Amp, but it has a 12-foot cord, which would have been tough for me.

If you can get by with the 12' cord (make sure you measure!), I think I'd prefer the lower amperage with a slightly longer charge time - it shouldn't be very significant, but I'll leave comment on that to the electricians and engineers.
You have a point here .. low amp longer time is it better? giving the fact no warranty and the battery vulnerable to begin with
 

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If you are only using it for overnight charging, the extra 40 minutes would not make any difference. But if you need to charge your car quickly, for example after you get home from work and before you go out for dinner, then the extra few amps could become important.
 

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Discussion Starter · #6 ·
If you are only using it for overnight charging, the extra 40 minutes would not make any difference. But if you need to charge your car quickly, for example after you get home from work and before you go out for dinner, then the extra few amps could become important.
thank you your answer you have very good point i purchased the Clipper Creek LCS-25
i plugged in my dryer plug worked fine for 1 hour i got 14 miles
not bad..
 

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Discussion Starter · #7 ·
I installed the ls25 provisionally with timer.. PG&E Have new EV plan
Off peak 9c /kW peak 35c
Of peak start 10pm - 7am
Partial peak 7am - 2 pm cost 18c

Not sure really how much will cost to charge off peak and peak?

Any one know



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A max charge takes roughly 20 kWh. That's like a "max gas tank fill", where you often fill when it's not a "max", so these are "at most" numbers:

- for every 10 cents per kWh, a max fill is $2
- so at 9c/kWh a max fill is a bit under $2 (about $1.80)
- at .18/kWh it's closer to $3.60
- at .35/kWh it's 3.5x 2 or about $7.
 

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I've been away from PG&E-land for too long to know if this still works, but:

1) With solar PV, you generate high-value (high priced) electricity (peak generation is ~10 AM - 4 PM, same as peak sunburn hours ;) )

2) And, with TOU metering (and especially if you install batteries for a UPS, although that raises installation and operating costs) you can draw a bunch of low-cost electricity at night and then use only battery and solar PV power during the day

which can combine to pay off a solar PV system pretty rapidly, given the steep difference between "peak price" and "off-peak".

Let's say that between refrigerator, air conditioner, hair dryers, and any and all other "power eating" devices (pre-EV), you normally run 1500 kWh/mo with roughly 2/3 of the usage during the day/on-peak and 1/3 at night/off-peak (this is close to the overall state power profile so it's a good guesstimate start point). So, you use 1000 "peak" and 500 "off-peak" kWh.

If you can charge all this at "TOU EV" rate and pay (say) .35 and .10 respectively, that's $350/mo peak and $50/mo off-peak.

To solar-PV-generate 1000 kWh/mo you need about 33 kWh/day. Conservatively (?) estimating sun hours at 4.5, let's call that an 8kW system. At $4/watt installed (that's a low end installed price but not un-achievable), 8kW will cost $32k. If you can take the 30% tax credit, that shaves off $9.6k, leaving $22.4k. At $5/watt installed (more reasonable) it's $40k, minus tax credit of $12k = $28k.

Now, that won't actually eliminate all on-peak usage (generation and usage hours won't always match up) but let's keep running with these. Assume it does take out all on-peak, or $350/mo = $4.2k/yr in costs. With the $28k system the un-adjusted payoff time is 6.7 years. A no-battery, no-UPS system is essentially maintenance free and should have a lifetime of about 30 years, so you get 23 years of "free" electricity afterward, worth (similarly un-adjusted for time value of money) about $96.6k.

Even when you correct for all the missing factors here, this seems like a pretty good deal.

(I live in Utah, where we have cheap electricity, no TOU charges yet, etc., so there's no economic payback to the solar PV I put in, or at least, not yet. Part of the reason I went for a small system, just 2.7 kW. So far, with roughly 10 months of actual operation, it's generated 3680 kWh. At our average cost of about 10 cents this is only "worth" $368, but at $.30/kWh it would be $1104. Scaled to 12/10ths those numbers are $442 and $1325, for yearly return. My end cost is a bit tricky, I had solar PV and solar hot-water installed together and the accountant worked the numbers as a group since they both get the 30% credit. But assuming $5/W, 2.7 kW = $13500 - $4050 tax_credit = $9450. It will take over 20 years of generation to pay it off here. But in Calif, with 3x higher rates, 20/3 is again about 6.7 years.)

(Our electric rates are going up though, we're already at .12/kWh in summer as of a few months ago. So now I get the summer generation, which produces the most energy, when the rates are highest, and the winter generation, which produces the least, at the lower rates. So my yearly payback estimate of $442 is too low. It's hard to be sure, but eyeballing the graph, I get maybe 60% of yearly production at the higher .12/kWh rate and 40% at the lower winter .09/kWh. Hm, let's see what the back of the envelope gets with those... about 4400 kWh/yr, 40% in winter = 1760 kWh @ $.09 = $158; 60% in summer = 2640 kWh @ $.12 = $317; so 1 year = $475, bringing the straight line number under 20 years. Interesting ... guess it all depends what happens to rates in the next few years, now.)
 

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Ok I live in NJ I have a 16 KW system on my garage. I have 4 AC units in my house 5000sq foot home with a pool. Also I have a 40x70 barn/ garage. My electric bills use to be 500 to 700 a month after I installed my solar project 3years ago my electric bills run about 200 to 300 a month. My total cost was 60k less fed tax credit 18k. Also the state on NJ has a closed market to sales my srec's. I produce about 3 per month they are selling about 140 per. At the end of the day I think I'm way ahead of the game. IMHO


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Discussion Starter · #17 ·
@ct-fiskerbuzz
thank you so much very well explained for some one like me:D ,
i have question.. what size of solar to charge the car only?
 

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friend told me high income will not qualify, true?
I'm not an accountant or tax guy, but I think that because it's a tax credit, your income does not matter, the only thing that maters is the computation of "tax owed". The credit says, in effect, you already paid that much in taxes that year. So if the bottom line on your 1040 says "you owe ONE TREEELL-YUN DOLLARS" :D, then you subtract the 30%-of-whatever from that and owe a little less. The way you lose out on these is if your bottom line is already close to zero: if you owe just $1000, your credit of having "paid" $6k or whatever, reduces the bill to $0, you don't get the other $5k back. (The EITC is a "refundable credit", which this isn't; if this were one of those, you'd even get the $5k too.)

(I know deductions disappear with higher income.)
 

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@ct-fiskerbuzz
thank you so much very well explained for some one like me:D ,
i have question.. what size of solar to charge the car only?
Depends on two things, at a minimum:

- how much "sun-hours" do you get (SFBayArea is roughly 4.5 although it varies a lot from point to point due to microclimates)
- how much do you drive the car on battery?

Here's how to calculate.

(1) Compute battery recharge amount over the course of a year. Let's say you drive the Karma, on average, enough to use 40 kWh a week, 40 weeks a year (the other weeks you're away on business trips or vacations or whatever). That's 40*40 = 1600 kWh needed, in a year.

(BTW "40 kWh/week" is pretty low, that's like what I use, not like what a daily-commuter uses.)

(2) Turn that into kWh per day: divide by 365. That's about 4.38 kWh/day.

(3) Divide *that* by "sun hours" for your location. Assuming 4.5, that's about 4.4 / 4.5 or about 1. So 1 kW would cover the Karma's usage, over the course of a year.

This all (deliberately, for simplification) neglects the time of generation vs time of use. If you plug the car in to charge during the day, it charges at 3.3 kW. If your "1 kW" system is running full bore at that time, you'll be drawing 2.3 kW from The Grid. Here in Utah, where they just net it all out and ignore time of use, that works out fine. In Calif, your meter is charging you $.35/kWh during the day, and $.10/kWh at night, so it does not just net out that way.

If you want to make sure your car never raises the usage during the day, it's much more complicated. What if it's cloudy one day during the day? What if it's 5 PM and the sun angle is low so that you're not getting peak power? The simple method is: don't charge during the day....

If you're willing to live with some "slop", though, start with this: A system with a peak output of 3.3 kW would, when it's putting out its peak output, exactly cancel out the Karma's charging load. You can figure that a "real" system will be at 60%-or-more during "enough" of "enough" days, even with cloudy days and such, and take 3.3 / 0.60 = 5.5 kW as "probably big enough". But again, because of Time Of Use charges in PG&E areas, your best economics is to use this to offset all your high-cost electricity (not worrying specifically about the car), and charge the car at night. In fact, you want to use all your electricity at night (off-peak) if possible. Stanford U does this with their air conditioning: they make ice at night, and let the ice melt during the day.
 

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As you can see from this pix. I have a solar project at one of my other homes. It's a 32k system. My electric bills are 0 because I was able to put a very lager system in place. The whole house is electric. Hot water, heat, stove. Ect... I rent this house out and and I bill my renters for the electric use. Just and other way to make a little cash..again I was able to take the 30% tax credit which was a big saving. ImageUploadedByAutoGuide1380376593.975900.jpg


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