Paul's how NOT to convert a Metro

[Christ]

Originally Posted by vpoppv

So one of my Geos was sideswiped last Monday. The insurance is going to total it (no surprise there). I'm not sure how much I will get, but since I rarely get a lump sum of money, I was thinking that I wanted to spend the money somehow on the electric car projects. I think that the best use of the money would be solar panels. I was thinking about this:

45 Watt Solar Panel Kit

Would this setup be a good choice? Ideally I'd want to use it to be able to charge my car completely solar.

I've been told those kits don't last very long, and only put out 45W if you place them on the sun, as opposed to in it. No personal experience, though.

Personally, I'd say try it. For the price, if you get a year out of it, it's at least a good shot.

[bennelson]

I have that exact solar setup. If you wait for it to go on sale, you can get it for less than $200.

I bought that solar kit mostly with the idea of using it for test experiments. It works great for what it is.

The big deal with solar is that you need to think about how much total energy you need.

That setup is 3 x 15 watt, 12V solar panels. So, you could rig that up as 45 watts to go to one 12V battery OR as 15 watts to each of three batteries for a 36V system.

When I plug in the 72V charger on my car, it usually pulls somewhere around 1200 to 1500 watts. Those little solar panels are NOT going to put out anywhere near that.

The other thing to keep in mind is time.
While I don't recharge my car with those three little solar panels, I COULD recharge my electric riding lawn mower. The trick there is that I let all the panels recharge one battery ALL DAY. The next morning, I would connect the panels to the second battery, and then the third one the day after that.

The mower has smaller batteries than the car, and has nothing better to do than sit on the lawn soaking up the sun anyways.

Also, where is your car when the sun is shining? If you drive to work in the morning, and the car is there all day, the sun shining on solar panels at home won't help you.

I am a big fan of running EVs from solar. However the easiest way might be just to join a renewable energy program through your utility. Otherwise, solar panels on your garage, running to you car would be another good choice.

You could also put one or more of those solar panels on your car to recharge the car's original 12V accessory battery. It would keep that topped off, and reduce recharging from the wall or from a DC/DC converter. If you do that, be prepared to answer everyone's question about how far you can drive on those three little solar panels......

-Ben
Electro-Metro

[vpoppv]

Ben,

Thanks for that very helpful post! I guess this won't be nearly enough to get my car charged though. How I was thinking of setting up the solar panels was to charge a bank of 12v batteries in parallel (I have about 11 batteries that have been just sitting there waiting for my lazy butt to finish EV2). It looks like I'm going to need a 1500 watt inverter. Then run the battery chargers for my car off the bank. Could I use this setup maybe once a week and let the solar panels charge the bank the rest of the week? Or would the loss through the inverters make me lose most of the energy I get from the panels?

[rmay635703]

Originally Posted by vpoppv

Ben,

Or would the loss through the inverters make me lose most of the energy I get from the panels?

Yes.

I can't remember the voltage of your car but if its 60v or less the Kaneka GSA-60 will charge it and you can buy them for $99-113 EACH individually. Usually about $150 with shipping (at least thats what I paid, I got one broken panel and one good one, hoping to fix the broken one since they didn't want it shipped back)
http://www.solarblvd.com/product_inf...lar-Panel.html

They are 60watt 67v panels meaning they can charge 48v effectively and 60v sslloowwly. They can float a 72v battery set as their peak voltage is approx 90 volts, can't really charge anything above 60v of lead though, unless they are discharged.

You would have to devise your own method of shutting them off though, if you plan on leaving the thing sit around a lot.

I've wanted to mount one panel on the roof of the Miles ZX40 mini van as a trickle charger/maintainer but as of yet haven't located cheap MC cabling to maintain the warranty. All of the MC cables cost almost as much as the panel it seems. I would love to find a nice 30' section of 20 guage MC extension cable for the mini van wiring but don't want to spend $60 on 10guage to run a 1amp panel. The other trouble is the flimsyness of the panel, I figure high density foam underneith to mount so it doesn't instantly crack in half.

Cheers
Ryan

[vpoppv]

Wow, 1 panel is 60 watts for $85!! That's the big problem, I overthink everything and I know absolutely nothing about electronics and solar. I think I might have to research for a year before I figure out what I need/want!
As far as my main problems: it's 72v. Car is parked at work during the day. So I think inverter losses are a necessary evil. I think that the panel you mention is just the panel. What I like about the kit is that it has the voltage regulator too I think. Argghhh. I just need to research.

[bennelson]

I have several of those Kaneka panels.

It would be ideal to run a couple of those to a 48V electric vehicle. (I happen to own two - a motorcycle, and a Citicar, both are 48V)

By keeping everything at that same voltage, and not converting DC to AC to DC, it should actually be very efficient.

Still, check with your utility on if they have a renewable energy program. Usually you are charged a couple bucks more per month to get energy from renewable sources. Your extra cash goes to help build more windmills, bio-gas plants, solar, etc.

My electric bill is about $35 a month, INCLUDING, the green energy surcharge.

[vpoppv]

Originally Posted by bennelson

I have several of those Kaneka panels.

It would be ideal to run a couple of those to a 48V electric vehicle. (I happen to own two - a motorcycle, and a Citicar, both are 48V)

By keeping everything at that same voltage, and not converting DC to AC to DC, it should actually be very efficient.

Still, check with your utility on if they have a renewable energy program. Usually you are charged a couple bucks more per month to get energy from renewable sources. Your extra cash goes to help build more windmills, bio-gas plants, solar, etc.

My electric bill is about $35 a month, INCLUDING, the green energy surcharge.

Our local utility is horribly antiquated. Most of our electricity is purchased by the city from GRDA, Grand River Dam Authority, which sounds nice, except that most of the power is not from the dam but from a coal plant about a half hour from here. When GRDA charges too much, the city fires up their diesel generator. The kicker is that they have three generators from the 1950's that they keep on standby "just in case". In other words, they continually pump warmed coolant through them 24-7 so that they are ready on a moment's notice. Who knows how much energy they use for this. The foreman informed me that it has been many years since those generators were used. What a waste. But I digress. While GRDA has great programs, my city offers none.
It looks like the biggest hurdle to overcome is inverter loss. Maybe I should run my car 48v for kicks and see what happens?

[vpoppv]

Man am I stupid. I needed this controller like I need a hole in my head. It's too much amps for the Geo, and I'm using the Open ReVolt in the Toyota:

curtis controller model 1221: eBay Motors (item 320540030905 end time May-31-10 13:29:46 PDT)

I can put it up on my shelf next to the 1209B that's been sitting there for months

[Tweety]

Simple math (TM) says that 12*6= 72V... And if you want to charge a 12V battery, the easy solution is to apply ~14V... That's how an ICE does it... 14*6 = 84V and 84/12 = 7...

So 7 12V batteries will charge a pack of 6 12V batteries with acceptable losses... an 8 pack at 96V is even better... and even better is that it splits into two 48V packs... And a Kaneka panel will charge a 48V pack...

Two Kaneka's and 8 spare batteries makes a halfdecent charger for a 72V EV... 16 batteries is even better... And you seem to have batteries...

[vpoppv]

I called my battery supplier, a boat place about a half hour from here, for the monthly check of their core supply. What I heard was "the number you have reached is no longer in service......". I quickly logged on to their website, and it's gone.