Electric car + solar panels FTW?

[madoka]

Has anyone researched the numbers behind installing a solar panel system for the home and an electric car? Is this a recipe for never having to pay for fuel again?

 

[Eli]

Sure.

But the initial investment is major $$$$$$$$$$$$$.

 

[madoka]

Home Depot offers $0 down and $110 a month:

http://www.homedepotsolarcity.com/about-financing.aspx

The way they describe it, there's no way to lose with their offer.

 

[ShawnD1]

Has anyone researched the numbers behind installing a solar panel system for the home and an electric car? Is this a recipe for never having to pay for fuel again?

Sounds totally unrealistic.

To put this into perspective, 1 horsepower is 746 watts.
Newegg has a solar panel for sale that is $95 and charges at a rate of 15W.
Redlining a piece of shit 100HP Prius for 1 second consumes as much energy as that solar panel collects in 4973 seconds (that's more than an hour!). Even if you covered the entire car in solar panels and it cost more than a house to do it, the car would still suck. You'd need to charge it for hours before you could even go up your driveway.

 

[Arkaign]

Fwiw, Solar has tremendous potential, but it all depends on a major breakthrough in efficiency. In other words, solar energy contains immense energy, but current solar tech is still really bad at converting this energy potential into electricity.

Using current solar tech, even with the most efficient panels, you'd need a lot more area than a car has to charge efficiently.

You also run into the problem of available solar energy. It'd be pretty good in some areas, terrible in others.

 

[madoka]

Just to clarify, I mean, installing a home solar system and using the energy is generates to power a plug-in electric car such as the Leaf. By no means am I asking for solar panels to be installed on the car itself.

 

[Arkaign]

Just to clarify, I mean, installing a home solar system and using the energy is generates to power a plug-in electric car such as the Leaf. By no means am I asking for solar panels to be installed on the car itself.

Ah! That makes more sense. A few solar panels on a car to help with the DC load of a few things or to do trickle charging might work, but yeah, having a bunch of solar on a house is much more sensible.

The cost of entry is steep, but maybe you could look into incentives, rebates, sponsorship, whatever it takes to help with the costs?

If I could have a ranch or something off the beaten path with a couple of fields of good solar panels (tough enough to withstand the odd hailstorm), I'd be a pretty happy camper. It'd be nice to be able to drop off the treadmill of urban life, and to be truly self-sustaining for a few years while writing a couple of novels or just relaxing with fishing, hunting, reading, growing crops, etc. Combining that with a solar-charged electric car would be a nice benefit, though I'd prefer something like a small electric-converted CJ. A diesel hybrid would be cool too, could afford to make a bit of biodiesel with a setup like that.

 

[JCH13]

Sounds totally unrealistic.

To put this into perspective, 1 horsepower is 746 watts.
Newegg has a solar panel for sale that is $95 and charges at a rate of 15W.
Redlining a piece of shit 100HP Prius for 1 second consumes as much energy as that solar panel collects in 4973 seconds (that's more than an hour!). Even if you covered the entire car in solar panels and it cost more than a house to do it, the car would still suck. You'd need to charge it for hours before you could even go up your driveway.

1) You'd NEVER buy solar panels from NewEgg for anything more than idle curiosity, unless you're totally silly.

2) OP is not talking about putting them on the car itself, but charging the car with a home array.

3) OP doesn't care about performance, OP just doesn't want to pay for gas.

To OP: take the maximum output of the solar array, multiply by your expected available charge time, and then multiply by 15% (the panels hardly operate at peak efficiency). See if that's what it'd take to charge up your car. You'd then have to do one of two things: use battery storage and an inverter to charge your car with AC. Or, my favorite, hack your car and charge the DC battery packs with a custom charger. You'd still probably need battery reserves to buffer power from the solar panels.

 

[ShawnD1]

Home Depot offers $0 down and $110 a month:

http://www.homedepotsolarcity.com/about-financing.aspx

The way they describe it, there's no way to lose with their offer.

That brings up another thingy about solar energy. A house and a car are in the same ballpark for energy consumption.

I think the ghetto house my parents had from the 1970s had a 100amp service, and houses are serviced in 240v. That's a maximum value that nobody actually hits.
Similarly, a honda civic has 140HP at a super high rpm nobody hits. 140 * 746 / 240 = 435 amp service equivalent!?!? jesus!

So right away we notice that a car uses a fuckload of power. Driving to the grocery store has higher energy demand than every appliance in your house combined.

Putting solar panels on your house is still a good idea if the price is right. You either charge your car with coal power or you charge it from solar power. Sometimes solar is cheaper. It depends where you live. Some places have hydro power which is incredibly cheap, so solar is never worth it in those regions.

I totally forgot the point of this thread. In summary no you cannot run your car from 100% solar (unless you very rarely drive). We can't even get houses to run 100% solar, and a car uses more power than a house. That's a little tiny Honda Civic that uses 4x as much power as a house. Think of how much power it takes to run an electric minivan.

 

[JimW1949]

I like the idea of solar panels and I think that eventually the cost to output ratio will be much better than it currently is and then it will be much more desirable. But for right now, at the current level of solar panel technology, I don't think it is worth it. I am sure some people here will disagree with me, but that is my personal opinion.

 

[JTsyo]

I think the key to solar is going to be collecting it in space with very large arrays, 24X7. On the ground it's just a supplemental source.

 

[Apex]

I like the idea of solar panels and I think that eventually the cost to output ratio will be much better than it currently is and then it will be much more desirable. But for right now, at the current level of solar panel technology, I don't think it is worth it. I am sure some people here will disagree with me, but that is my personal opinion.

I think it depends heavily on where you live. In the sunny states, it may already be worthwhile.

For instance, we recently installed a 6.5kW system at our home.

It's outperforming the initial estimates from our planning stage, and the expected break-even point should be under 5 years (not counting the increase in home value from the setup which ranges from $3.50-$5.50 per watt depending on where you live).

With cheaper setups coming online now (ie. Dow solar shingles), the systems should pay for themselves more quickly than mine.

In terms of using it for a car though, you'll probably want more than a 6500w system.

 

[ShawnD1]

In terms of using it for a car though, you'll probably want more than a 6500w system.

What prevents people from getting the bigger one? Does the cost go up faster than the wattage?

 

[Apex]

What prevents people from getting the bigger one? Does the cost go up faster than the wattage?

I think it all comes down to money and available space.

I have 28 panels on my roof. Basically, the back 1/2 of my roof is almost flat, and the panels are installed at an ideal 15 degree tilt (ideal for the location), covering virtually that entire space.

Bigger systems should cost less per watt, though not in a linear way (for instance every time you need to bump up the PV inverter size).

 

[LTC8K6]

Our HQ went almost totally solar a while ago. Massive tax credit made it reasonable. I think the system is close to paid for now. It runs most of the plant, and excess power is sold back to the grid. They rarely pay for electricity any more. There's a web site where you can go and watch the power flow, but I can't recall the link. The factory is in Pennsylvania.

 

[JimW1949]

I think it depends heavily on where you live. In the sunny states, it may already be worthwhile.

For instance, we recently installed a 6.5kW system at our home.

I agree, where you live will no doubt make a difference. Also, how much of a tax credit is available at the time of purchase will matter too.

Here is Wisconsin we have a lot of sunny days during the Summer months, but when Winter comes we get cloudy days and snow. I am assuming the snow would have to be removed from the solar panels and I am also assuming that when the snow melts and turns to ice, then the ice will need to be removed from the solar panels as well. I am not even sure how that would be done. What I mean is, I would think the solar panels would be a bit on the fragile side, so getting an ice scraper to remove the ice probably wouldn't be a good idea. An ice scraper probably wouldn't do the job anyway. Getting on the roof with snow and ice would more than likely pose a problem too.

 

[Pulsar]

Solar panels are a non-starter. They are too costly, too inefficient, and their lifespan is too short. They are not feasible as an actual green technology, especially if you consider the energy cost to build them, which few people do.

 

[Gibson486]

Yup, at my former job, we partnered with a firm. The partnering firm wanted to install solar panels. In the end, the client spent over $2 million dollars in solar and only got enough power for a 40HP motor. Not a great investment.

 

[Doppel]

Yes you can do this easily. By easily of course I mean if you have tens of thousands of dollars for the necessary sized solar array. That is unless you only want to drive a couple of miles/day.

 

[WackyDan]

Sounds totally unrealistic.

To put this into perspective, 1 horsepower is 746 watts.
Newegg has a solar panel for sale that is $95 and charges at a rate of 15W.
Redlining a piece of shit 100HP Prius for 1 second consumes as much energy as that solar panel collects in 4973 seconds (that's more than an hour!). Even if you covered the entire car in solar panels and it cost more than a house to do it, the car would still suck. You'd need to charge it for hours before you could even go up your driveway.

You need a bit more education. Multiple solar panels would provide enough amperage to charge the car provided the weather isn't crappy, etc... That is where a grid tied system would take over. Best of both worlds, but I wouldn't install a system that is dedicated to just charging the car.

 

[Apex]

Solar panels are a non-starter. They are too costly, too inefficient, and their lifespan is too short. They are not feasible as an actual green technology, especially if you consider the energy cost to build them, which few people do.

Lifespan too short?

 

[DougoMan]

Sounds totally unrealistic.

To put this into perspective, 1 horsepower is 746 watts.

Tho I know this is technically correct, I can't believe that a 200hp electric car is pulling anywhere near 150,000 watts.

 

[JCH13]

Tho I know this is technically correct, I can't believe that a 200hp electric car is pulling anywhere near 150,000 watts.

It's actually pulling more, because the motor is not 100% efficient.

 

[novasatori]

So Apex that cost you $18k ? How much space does it take up on your roof?

I gotta say that is pretty awesome. Any sites to find more specific information? Your pics have definitely piqued my interest (not for an electric car though).

Also if you don't mind sharing what City you live in, I see you're in S CA.

 

[Apex]

So Apex that cost you $18k ? How much space does it take up on your roof?

I gotta say that is pretty awesome. Any sites to find more specific information? Your pics have definitely piqued my interest (not for an electric car though).

Also if you don't mind sharing what City you live in, I see you're in S CA.

Yeah, about $18k after rebates and credits. The rebates and credits accounted for roughly 1/2 of the total system cost (so the initial total was $37k). The solar installer actually fronted the money for the rebate, so they take it right off the top (you don't have to wait for it).

I think there are cheaper routes now, for instance this 5kW system from costco (Just need to install it or get it installed (in CA, you need an installer who will warranty for 10 years for the utility rebate):

http://www.costco.com/Browse/Product...*90897*&topnav

I'm not sure exactly how much space it takes up. However, regulations require something like a 3' space around the edges of the roof with nothing installed. There's plenty of space between the panels too, so that they don't cause a shadow to fall on any other panel.

The panels I went with were the 235w Kyocera KD235GX-LFB. They're +5%/-3% tolerance, 209.4w PTC panels. PTC is the important spec to look for, along with the tolerance. They're certified to only degrade down to 80% of peak power output after 20 years.

This install is in Palos Verdes. It's definitely not an ideal location because of the amount of fog we get there. Even so, it's been performing spectacularly, as you can see from the SoCalEdision report. Despite being in some of the more rainy/cloudy/foggy months of the year, it's gotten our bill down to negative numbers. We had only expected a system this size to get the bill down to $60-70 per month.