Vehicle solar panels to grid

[oil pan 4]

I searched and it looks like no one has tried this on here yet, which is surprising.
So far I have 24 watts of solar panels installed on the vehicle and 140 more watts on the way. I was thinking about it today and seemed like these solar panels with the genasun charge controller, I just made up the worlds most expensive battery tender when its not needed.

Need to get some more use out of the solar panels. This is the setup I was considering. Very simple. Take the solar panel and split the output between the grid tie and Genasun MPPT charge controller. The cheap grid tie electronics coupled with the advanced MPPT electronics should work quiet well for "running both at the same time" for my purposes. The Genasun's MPPT electronics will try to gobble up even as little as 8 volts to charge batteries. The very simple electronics of the grid tie inverter actually need more than 14 volts to start working well.

If that doesn't work then I just wont plug it in until later till after I know the battery is charged.
And no the battery voltage will not reverse feed through the charge controller.

Not too long ago I was going through some boxes in the out building and found my old 300 watt grid tie inverter I bought in 2008 to do some grid tie experiments with micro wind power.

That's my old 12 to 28 volt grid tie inverter. From what I can remember when testing on the wind turbine it made 20 to 30 watts at 12 volts. Then at 24 volts (only obtained through force feeding battery power to inverter) it made 240watts and over heated. That is why I hole sawed a 3 inch hole in the top of the inverter and covered it with a fan. I could not induce an over heating fault after that mod. The fan is powered with DC input voltage.
If you look closely you can see where I cut the wires so I could power the fan with 12v and feed the inverter 24 volts. All I need to do is reconnect the wires.
Since the power company installed a dumb smart meter that is so advanced it only knows how to count up, any power I produce this meter would count as consumption, that removes 2 huge threats to the power company. 1, people who steal power and 2, the people who generate and grid their own.
How to defeat the dumb smart meter: It just so happens I have most of my vampire loads on one circuit, I could easily move the rest over and this circuit. Also this circuit shares a wall to the garage and I already tapped into it so I would have an additional 120 volt circuit out in the garage to use. Now all I have to do is install the inverter, add some fusing and back feed power on to that circuit.
There you have it, vehicle meet grid; grid meet vehicle.

[JRMichler]

Originally Posted by oil pan 4

Take the solar panel and split the output between the grid tie and Genasun MPPT charge controller. ..... The Genasun's MPPT electronics will try to gobble up even as little as 8 volts to charge batteries. The very simple electronics of the grid tie inverter actually need more than 14 volts to start working well.

Also this circuit shares a wall to the garage and I already tapped into it so I would have an additional 120 volt circuit out in the garage to use. Now all I have to do is install the inverter, add some fusing and back feed power on to that circuit.

I think the first part will work, but the second part will not. All 120 volt circuits go back to the panel and the meter, so you will backfeed no matter where you connect.

Here's another idea. Store the excess energy in hot water. Install an electric hot water heater in line before your existing hot water heater. Then run the electricity from the panel into the first hot water heater. 240 volt elements will work just fine on 120 volts, they just pull less power. This approach depends on the solar panels not producing enough power to boil the water, which should be the case here. Worst case, the relief valve pops.

[oil pan 4]

Ultimately I just need to call the power company and get a smart meter that knows how to count up and down. But I have a sneaking suspicion they will surcharge me more for that kind of meter.
The ghost load cluster is made of TV, DVR, Modem, laptop and various wall warts. I could move another big ghost load over to the garage circuit, just by plugging the fridge into another outlet. Got to love 1960s wiring, everything 120 volt powered was on 4 circuits.
The fridge likes run an 70 or 80 watt deicing element after the fridge turns off, then it will draw 10 to 20 watts for what seems like hours on end for the magnetic seal warmers.
All my hot water heating is natural gas.

I can get a fairly cheap 2 way inline power meter that will let me know if I am pushing any current back to the meter.

[oil pan 4]

Well it works, tested on a solar panel.

I rigged up an 80 watt mono panel that I will not be putting on the vehicle.
The Genasun MPPT charge controller is installed under the air comprssor.
Then I just kind of stuck the grid tie in there on a kill-a-watt meter just to see if it would all work and it did.

The grid tie is on the input side of the charge controller. Once the battery is full the grid tie will soak up more power.
The grid tie is just sitting in there, its permanent place will not be in the vehicle.

With out the grid tie inverter connected it was doing this:
The genasun MPPT controller was doing its MPPT thing for sure. It had 15 volts, 3.1 amps going in from the solar panel and 12.9 volts and 3.5 amps going out.
If this were a regular PWM controller, it would be 3.1 going in, and maybe 3 going out.
Its sorcery.

With the grid tie and charge controller going the solar panel was sending 3 amps to the charge controller and 0.6 amps to the grid tie (and 0.1 amps to the fan).
With the charge controller disconnected (simulating full battery) the grid tie put out up to 30 watts.

The solar panel I am putting on the suburban are 17ocv. I reckon I will series up 2 of them for a max voltage of 34 volt, which is the max input voltage on the genasun.
This will work better with the grid tie.
I think if I put all the "12 volt solar panels" on there in parallel I am thinking that I would only get 50 watts. With the panels wired in series parallel for "24 solar panel volts" it will push more like 100+ watts on to the power grid. That is if I need more than 100 watts on my houses vampire circuit.
EDIT, the panels are actually 21 to 22 volts OCV and I wired them all up in parallel because if I put them in series they would send up to 44 volts to the charge controller which would fry it.

[Daox]

Fun mod!

I take it the genasun doesn't have a 'dump load' feature?

[oil pan 4]

It only has the solar panel input and battey output.
Its working perfectly for my needs.

[oil pan 4]

The first 10 out of 14 small 10 watt solar panels are here and I have the weekend off.

[oil pan 4]

I got the panels in and I am in the process of testing/playing with them.
So far they put out 21 to 22ocV and can push a half amp through a 12.2v battery when orthogonal to the sun and 0.4 amps when laying flat.
I have some of them hooked up to the grid tie inverter, 3 panels push 17 watts on to the power grid while laying flat.

Next I just need to get more pematex high temperature orange RTV and start drilling holes. I used pematex orange high temp last time so I know it lasts at least 3 or 4 years.

Edit: I hooked up all 10 panels together and its working better than I expected. 10 panels are making 55 watts of power. I am thinking 14 will make maybe 70 watts.
I can get a few more watts if I depower the fan. The tiny little 1 inch by 1 inch fan it had originally worked fine up to about 100 to 150 watts. Anything more than 150 watts it over heated and shut down pretty quickly.
The "12 volt fan" is running on 15 volts. I think I could put a 24 volt fan on there or add a resistor.
The fan is gobbling up 5 to 10 watts more than it needs to.

[hootis]

I don't see the point of using the solar in your car to go back to your house. I am thinking about putting two 100 Watt solar panels on my car, adding a second or larger battery then after some testing remove the alternator. I estimate I will, on average get 100-125 watt/hours during the day, out of the 200 watt system because they will never be angled correctly towards the sun. If you are just charging a car battery you don't need an inverter. So lets just say you never drive your car you have 200 watts of panels and they are angled perfectly towards the sun. This would be the best case. This is not going to happen. But in that case you would get 10 hours of sun a day avg that would be 1400watts. If I buy that much electricity it would cost me $0.25. So how much time and money will you sink in to get $.25 a day? It is not worth it, to buy the inverter and try to figure everything else out.

If you want to get solar on your house it is worth it defiantly. But you put those panels in the proper position so they get full sun light and it will equal the cost of buying electricity after a few years. Absolutely does not make sense to feed back from your car to the grid.

TLDR;I think its also worth putting some solar on your car, simply because the sheer inefficient of alternators, the complexity and limitations of the systems are not a good idea together.

[oil pan 4]

The point of the grid tie is to make use of the solar panels after the battery is charged. I work 12 hour shifts so I am only at work 13 or 14 days out of the month. This will make some use of the solar capacity during those off days when I don't drive it.
I am putting a lot of solar capacity on there, 100 watts right now, 40 more watts worth are in the mail and I may expand it further up to 200 watts.

I bought the grid tie inverter in late 2008 for wind power experiments. The results of the experiment were obviously not favorable to small wind power production so the inverter has been shelved since early 2009. I didn't buy it for this project.
Not using the inverter would be a waste of money and I already figured everything else out.

This is the deal I offer to the ecomodde community. I will get it figured out so you don't have to. That's it.
Now all anyone else has to do is copy what I did and scale it up or down for their own ends.

The solar panels are going on there to support the electrical system when I do an alternator delete. The way solar is, when you think you have enough capacity you always fall short. I am going to over do it so I always get the battery fully charged and have extra power.
I would also like to be able to have some power for away projects, camping and anything else that might come up so I don't always have to drag this thing around:
Home made solar inverter generator hybrid - EcoRenovator