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Solar Charging an EV

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Looking into adding solar panels to power my home. With all of the talk about the impact of EV on the utility grid, it would make since to expand the capacity to have enough capacity to charge an EV.

Does anyone have an idea how and what size of a system I would need to charge an EV?
1Kw, 5Kw, etc
Battery switch so that it charges during the day or can the energy be stored and charge my EV battery at night?

Thanks for your insight.
 
Battery switch so that it charges during the day or can the energy be stored and charge my EV battery at night?

If you really want only solar-generated electrons in your car, you will either have to only charge during the day, or set up some sort of local storage system.

But I think it's better to skip the storage and just plug the solar panels in to the grid. The grid will get the power when it needs it the most, and then you can withdraw functionally identical electrons to charge your car when there is excess capacity. It is true that your car won't have "pure" electrons, but somebody else got them at a more critical time, so the whole system benefits more that way. And you didn't have to buy the storage system.

I'm assuming you're mostly interested in doing the "clean" thing. If you want to do the "independent" thing and be able to charge your car (or maybe run your house) during a power outage, then a local storage system could make sense.
 
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...I think it's better to skip the storage and just plug the solar panels in to the grid. The grid will get the power when it needs it the most, and then you can withdraw functionally identical electrons to charge your car when there is excess capacity. It is true that your car won't have "pure" electrons, but somebody else got them at a more critical time, so the whole system benefits more that way. And you didn't have to buy the storage system...

I think a lot of us concluded that is the answer.
When I got into solar to power my EV some years back I liked the idea of a self-contained "island" system with storage batteries directly connected to the panels, but it just made more sense overall to go with grid tied and skip the storage part. I concluded that in part based on the fact that my house has generally reliable power delivery from the grid. Also the batteries tend to be the part of the system likely to fail first.

On the other hand, if you live in an area where the grid connection goes down frequently then something with local energy storage and a standalone (non-grid tied) inverter starts to make sense just from the added benefit of providing emergency backup power.
 
I am planning on tearing down my house and building new... Since I live in Houston (a hurricane prone location), I find it appealing to have storage for the power from the solar cells. It could never run my full home, but it would be nice if it could run at least 1 A/C unit, the fridge, a light, a TV, and charge my car for a period of about a week. I was thinking about leasing the equipment from a company like Solar City. Anyone have experience with that?
 
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I am planning on tearing down my house and building new... Since I live in Houston (a hurricane prone location), I find it appealing to have storage for the solar cells. It could never run my full home, but it would be nice if it could run at least 1 A/C unit, the fridge, a light, a TV, and charge my car for a period of about a week. I was thinking about leasing the equipment from a company like Solar City. Anyone have experience with that?
Ok.. took me a moment to realize that you meant a battery system as opposed to a shed to protect your solar cells from a hurricane.
 
The panels are probably strong enough and could be mounted security enough to handle very extreme weather.
I think the point was to have them (for emergency power backup when the grid is down) not a worry about needing to protect them.
 
To be even more clear... (for those of you who do not live near hurricane areas):cool:

When a hurricane hits, power lines go down all over town. Power can be out for a couple hours or 6 weeks. Where I live, rarely is power out more than 1-2 weeks. During that time, the weather is still HOT and we need A/C to sleep. I would also like it if the milk in the fridge didn't go bad. Even though the sun goes down late in hurricane season, it is still nice to have light to read at night... also a TV to watch to keep up with the news would be nice.

So, does anyone have experience with a combined battery-grid system. And can Solar City set you up with one of those... with no money down?

Will Solar City put my batteries in a shed? :wink::biggrin:
 
I wonder if the local storage system could be another Model S battery? I mean if they are user swappable...

~60-90 KWh of juice would be pretty sweet. Too bad using the Roadster as a stationary power source voids the warranty :) Pretty bummed I can't hook up a big inverter to it haha. Would be really cool if the Model S had some AC sockets in it!
 
I have spent the past 18 months researching and keeping track of residential solar array technology. Although
originally I wanted to go off the grid, recent developments and careful thought convinced me to go the grid-tied
route with net-metering. The utility needs to install a meter that can account for power into and out of your home
and usually will do so for free. Most states require that the power you put on the grid must match that you take
off in terms of whether it involves peak or non-peak time of day. Peak power you send to the grid can offset
peak and non-peak you extract from the grid, but off-grid production you put on the grid can only offset off-peak
consumption. I think those rules apply in most places. Check with your utility. Remember that the Feds provide
income tax writeoffs of $1000 per kilowatt of solar capacity you install, up to 6 kilowatts. You shoud therefore aim
at the next higher integer number of kilowatts beyond what you think you'll need, if you are below the 6 kilowatt
power level. Costs for the panels (by far the greatest expense) can run anywhere from $2 to $3 and more for
silicon crystal (as opposed to thin-film) and the recent advent of microinverters, either seperate for each panel, or
what's coming soon, installed on the panels themselves, are the other significant expense. Mounting rails and electrical
wires, breakers, etc are insignificant, cost-wise. Labor required is pretty minimal as is knowledge required. Micro inverters
make installation so simple that a seven year old with access to YouTube will have no problem at all. If you want to
figure out how much power your array will harvest, look up the solar irradiance figures for your locality (it doesn't
have to be all that close - virtually all locations in North Carolina, for example, show pretty much the same solar
irradiation levels). Make sure you get a building permit and have it inspected, to cover your ass should your house burn down
and the insurance company suspects that your array is to blame. If you have the appropriate space, mount the panels on
the ground by building framework there. It makes everything so much easier and allows you to tilt them to the very best angle.
panels (and microinverters to come) are warranteed for 25 years, but produce power way beyond that. My estimate for
North Carolina , assuming installed by myself and taking the Fed subsidy, shows that I can reasonably expect the power to
cost between 5.5 and 6.5 cents per kilowatthour.
 
Record breaking run:
http://www.sunswift.com/
Sunswift has broken the Guiness World Land-Speed record for a solar-powered vehicle. The record was set at 88km/h by Sunswift IVy on the 7th of January, 2011. The previous record was set by General Motors Sunraycer, which travelled 78km/h on roughly 1500 Watts.

...This means that Sunswift IV, with ~25% less power than the previous record holder, went 13% faster. We've come a long way since 1988.
 
Record breaking run:
http://www.sunswift.com/
Sunswift has broken the Guiness World Land-Speed record for a solar-powered vehicle. The record was set at 88km/h by Sunswift IVy on the 7th of January, 2011. The previous record was set by General Motors Sunraycer, which travelled 78km/h on roughly 1500 Watts.

...This means that Sunswift IV, with ~25% less power than the previous record holder, went 13% faster. We've come a long way since 1988.