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This time they claim it's gonna charge the car's HV battery.. good luck :) seems like it's going to stay a concept for a while.
http://www.engadget.com/2014/01/02/ford-c-max-solar-energi-concept-/
It's hard to imagine that you can get enough power out of four small PV panels on the roof of a car to charge the HV battery. I have the entire roof of my house covered with PV panels and they can barely supply enough power for the Karma's anemic 3.3 KW charger.

On the other hand, if you could tow one of these behind your car, it may be possible to charge the car using solar panels on the go. And when you stop for the night, you can use the wind turbine. :D





Photo Credit: @Marswill (the owner of the Inferno Karma in the shot) via this post.
 

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Classic Fab! I think a Geo Thermal unit would finish the resource centre but not your portable needs. I use Geo Thermal for home heating and cooling and can't understand why more folks do not go this route. Karma applications look a bit remote :)
 

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Classic Fab! I think a Geo Thermal unit would finish the resource centre but not your portable needs. I use Geo Thermal for home heating and cooling and can't understand why more folks do not go this route. Karma applications look a bit remote :)
Even better than geothermal: tide power.



Geothermal is a great solution but fairly expensive to implement and you need a minimum spread between the ground temperature and the average air temperature to make it viable financially. You also need to be able to use it for both heating and cooling. I looked into getting it here in San Francisco, but since it almost never gets warm enough here to have to use the cooling side, it was not really economically viable.

I got a solar PV system instead which has turned out to be a great decision, particularly since when I got the Karma.
 

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Even better than geothermal: tide power.



Geothermal is a great solution but fairly expensive to implement and you need a minimum spread between the ground temperature and the average air temperature to make it viable financially. You also need to be able to use it for both heating and cooling. I looked into getting it here in San Francisco, but since it almost never gets warm enough here to have to use the cooling side, it was not really economically viable.

I got a solar PV system instead which has turned out to be a great decision, particularly since when I got the Karma.
Fab, up here in Canada, the payback on our heating costs ( read winter) was 3 years and now $4300 per year in savings. The geothermal is most efficient at cooling which is a lesser need in our shorter summers. What were capital costs for the solar PV system and the company whose solar system you used? txs
 

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Fab, up here in Canada, the payback on our heating costs ( read winter) was 3 years and now $4300 per year in savings. The geothermal is most efficient at cooling which is a lesser need in our shorter summers. What were capital costs for the solar PV system and the company whose solar system you used? txs
Our weather here is mild year-round and our Natural gas bill for heating, cooking, and hot water is less than $100/month. It would take decades to pay back the cost of a Geothermal system.

My PV system was designed and installed in 2008, so it's not exactly state-of-the-art today. It consists of 18 x 205W Sanyo panels and a Xentrex grid-tied inverter. After incentives and tax refunds, it came to around $25K. It saves us about $2K/year in electricity cost. I very recently switched to a new non-tiered rate from the local utility that is going to be cheaper overall, but will reduce the impact of the PV solar generation as well. Overall, I am pretty happy that we have the system, more for reducing our CO2 impact than the savings.
 

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Our weather here is mild year-round and our Natural gas bill for heating, cooking, and hot water is less than $100/month. It would take decades to pay back the cost of a Geothermal system.

My PV system was designed and installed in 2008, so it's not exactly state-of-the-art today. It consists of 18 x 205W Sanyo panels and a Xentrex grid-tied inverter. After incentives and tax refunds, it came to around $25K. It saves us about $2K/year in electricity cost. I very recently switched to a new non-tiered rate from the local utility that is going to be cheaper overall, but will reduce the impact of the PV solar generation as well. Overall, I am pretty happy that we have the system, more for reducing our CO2 impact than the savings.
Thanks Fab. Happy motoring.
 

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And I think systems have gotten a fair bit cheaper in the last 5Y as well (at least in Calif). Def worth considering.
 

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And I think systems have gotten a fair bit cheaper in the last 5Y as well (at least in Calif). Def worth considering.
I got mine in 2011 and the cost was very reasonable. My system has 24 235W Sharp panels. I did it on a 30 year lease but paid it all up front which was $13K. The advantage of a lease is that the solar company will track the performance of the system and provide necessary services at no additional cost. You can also check the performance of your system online. In my case, the payback is around 6 to 7 years.
 

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Question: does the Solar Roof on the Fisker really do something? It is there but what does it do?
 

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It adds charge to the 12 volt battery. If the 12V system is fully charged, the solar roof spins up some tiny fans that help air out the cabin, on the assumption that the sun is getting the interior hot.

Topping off the 12V system means that the 12V system does not need to be boosted from the high voltage drive battery as often. So, when you're out in the sun, the solar roof helps reduce the drain on electric-miles-available (it never makes it go up, it just slows down the rate at which it goes down, by some tiny imperceptible amount).

Since the solar roof is quite heavy, it adds to the weight of the car, which reduces electric mileage. Overall it's probably a wash.

But it looks cool. :D
 

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It adds charge to the 12 volt battery. If the 12V system is fully charged, the solar roof spins up some tiny fans that help air out the cabin, on the assumption that the sun is getting the interior hot.

Topping off the 12V system means that the 12V system does not need to be boosted from the high voltage drive battery as often. So, when you're out in the sun, the solar roof helps reduce the drain on electric-miles-available (it never makes it go up, it just slows down the rate at which it goes down, by some tiny imperceptible amount).

Since the solar roof is quite heavy, it adds to the weight of the car, which reduces electric mileage. Overall it's probably a wash.

But it looks cool. :D
I have always thought it is more of a design element than a functional one, and makes the car instantly recognizable, as if it was not already. The energy screen actually shows power being generated by the solar roof, but I doubt that it makes a measurable impact.
 

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The Energy Screen is working with you guys? With me it is just a static screen... always showing the same.
 

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The Energy Screen is working with you guys? With me it is just a static screen... always showing the same.
The solar screen is static and shows the same image all the time. I was talking about the main energy screen that shows the energy flow from the battery to the motor, etc. On that screen, when the solar panels are generating energy, the panels on the roof of the car's image light up. Here is a video someone put up:

http://www.youtube.com/watch?v=Y--eS2EJt0w&feature=youtu.be

There are also a number of threads discussing this, for example [URL="http://www.fiskerbuzz.com/forums/13-fisker-karma/1355-karma-cooler-sun-2.html"]this one[/URL] and this one, including my experiment that showed that the solar panels do power ventilation fans,
 
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