ETFE Flexible Solar Panel Install on Ford Transit

[cargovanconversion]

It was finally time to install the flexible panels from Link Solar. I chose the 135W version as its length (59.5 inch), did fit the width of the Ford Transit's roof exactly. That meant optimal use of the roof area. Without a roof vent you'll be able to install 5 panels (675W), four (540W) if you have a roof vent installed and three (405W) like me, if you eliminate the front panel, because it is readily visible from the street. An Extended version of the Transit will support up to 6 panels or a whopping 810 watts.


https://youtu.be/3wdPW9I9S_Q?list=PLyrIiniKvmg5fw4iLGoeajpfCFETk2zT Y

I use 3M's VHB tape 5952 to create a leak-proof connection to the roof; the panels are virtually invisible from the street, except for the MC4 connectors.

You can read more on CargoVanConversion.com Flexible Solar Panel Installation | CargoVanConversion.com


https://youtu.be/p-ptxLDd9kw?list=PLyrIiniKvmg5fw4iLGoeajpfCFETk2zTY

[cargovanconversion]

The panels are now installed, the wiring laid on the roof; today I am placing the cable gland on the roof and pull an 8AWG MC4 cable through the roof.

View the video here

[BBQ]

.

Flexible panel is not my first choice,
but I am glad it works for you.

[cargovanconversion]

Originally Posted by BBQ

.
Flexible panel is not my first choice,
but I am glad it works for you.

I really don't know whether it will work for me. It's still a bit of a gamble. Preliminary tests show a good performance, but we'll have to wait and see.
Main reason is their stealthiness. Have waited years, but didn't want to buy the 'first generation' of flexible panels. Too many issues. These seem to be a lot better. I'll keep posting on their performance or issues that I may have.

Van Williams

[Phoebe3]

I have one 100 watt flexible Go Power! solar panel on my Transit. Seems to work very well. We have 210 ah wet cell capacity for the house and the panel keeps the DC refrigerator running.

Note that we do not have an inverter nor do we run much on battery power: refrigerator, roof fan, and some LED lights. The batteries do get run down overnight. Solar charging depends on sun and we also (usually) drive some during the day so I can't say how long we could go off grid. I'd guess, if there was sun, we could run the refrigerator indefinitely, but don't know about lights, fan and charging laptops. Right now, we just don't have the battery capacity. When these batteries die, I'll replace them with larger AGMs, then we'll know if we need to add another panel. YMMV.

As an aside, I will say that I would have preferred a rigid panel on a roof rack because it would shade the roof and reduce heat loading. I don't care about stealth, which is good because people come up and ask about the van all the time - there is no way I could pretend I'm not there.

[peteco]

Originally Posted by Phoebe3

As an aside, I will say that I would have preferred a rigid panel on a roof rack because it would shade the roof and reduce heat loading.

Can you tell the difference in temperature from before having the panel until now?

[GeorgeRa]

Originally Posted by Phoebe3

................
As an aside, I will say that I would have preferred a rigid panel on a roof rack because it would shade the roof and reduce heat loading. I don't care about stealth, which is good because people come up and ask about the van all the time - there is no way I could pretend I'm not there.

Indeed, one of those not often mentioned advantages of solar panels, they practically block IR from hitting the roof. Another one is the cooling effect by the airflow through the airgap underneath, solar panels are very sensitive to temperature and they do absorb a lot of radiation, but, if the stealthy look is in the driving seat everything can make sense. Time to invent an invisible paint, or a shrinking gun.

[cargovanconversion]

I still think that if you're not into stealth, that a rigid panel is a much better option. They're much less expensive and have a good track record.

Van Williams

[Phoebe3]

Originally Posted by Phoebe3

As an aside, I will say that I would have preferred a rigid panel on a roof rack because it would shade the roof and reduce heat loading.

Originally Posted by peteco

Can you tell the difference in temperature from before having the panel until now?

Our van came with the flexible panel so I don't have any before/after temperature comparisons. Because both the van and the panels are dark, I suspect there's not much difference. The panels are far too thin to provide insulation.

However, I once had a 1986 Mercury that was dark burgundy. We lived in the desert with daytime temps in the triple digits. The car was great but unbearably hot so we put a roof rack on it and and added a sheet of plywood painted white. VERY un-stealthy and would have reduced gas mileage except that in town, no speed limit was higher than 35 mph so there was little drag effect. We removed it if we went out of town.

I'd say it reduced the temperature inside the car by 10*F-15*F.

[BBQ]

Originally Posted by Phoebe3

I have one 100 watt flexible Go Power! solar panel on my Transit. Seems to work very well. We have 210 ah wet cell capacity for the house and the panel keeps the DC refrigerator running.

Note that we do not have an inverter nor do we run much on battery power: refrigerator, roof fan, and some LED lights. The batteries do get run down overnight. Solar charging depends on sun and we also (usually) drive some during the day so I can't say how long we could go off grid. I'd guess, if there was sun, we could run the refrigerator indefinitely, but don't know about lights, fan and charging laptops. Right now, we just don't have the battery capacity. When these batteries die, I'll replace them with larger AGMs, then we'll know if we need to add another panel. YMMV.

As an aside, I will say that I would have preferred a rigid panel on a roof rack because it would shade the roof and reduce heat loading. I don't care about stealth, which is good because people come up and ask about the van all the time - there is no way I could pretend I'm not there.

When you say "the batteries do get run down overnight",
did you start the night with a full charge?

Do you have room to add a panel?

[Phoebe3]

A second panel was an option on this model from Coachmen, but we bought off the lot. I don't know where they would put the second panel, but I have to assume there is space for one...

Yes, we start with a full battery (actually, two 105 AH wet cells), but since it isn't getting charged at night, naturally, it depletes. How much depends on how much dark there is (it appears as long as there is sun, the panel provides enough power to keep the refrigerator running without depleting the battery). In the winter, there is a longer period without sun and we also use the lights more.

So... the refrigerator uses 4.5 AH when it is running and the amount it runs depends on ambient temperature. I would guess 33% of the time, on average. That means it uses an average of 1.5 AH per hour so it depletes the batteries about 18 AH overnight. We have 205 AH to play with. The solar panel probably generates about 25-30 AH per day. Midday charging indicates about 3.5 AH.

So the single panel generates almost enough juice during the day to run the refrigerator AND top off the batteries.

Or, you know, we could just run the engine for, like, five minutes.

[booster]

One 100 watt solar panel used to be what "everyone" said was needed to cover the use of a compressor frig, but I fear the "everyone" who did the recommending didn't have one in the real world, especially now that they are getting bigger and using more power, and the fact that many suffer from poor installations so don't ventilate well and use more power than necessary.

Your 1.5 ah per hour is likely pretty close an estimate for moderate weather and would use 36ah per day. The typical estimate of decent recovery for a 100 watt panel is about 30ah per day in very good sun, so you will go downhill by the deficit for the frig and whatever else you use, every day. In clouds or rain, you could lose 25ah to the frig, so it counts up quickly.

I often tell people to forget about how much power you use during any given period of the day, unless you are searching to find reductions in use, and just look at your daily usage. Looking at smaller windows always seems to get folks way off in their calculations for some reason. My guess is that Pheobe3 would be using 50-70ah per day if they aren't big users of other power than the frig, so in poor solar conditions you could be out of power in two days, assuming you started totally full which is not likely for most people who are staying offgrid a lot, and even for some who do get shore power regularly but not great charging.

As has been discussed often here, the value of solar gets questioned a lot. I think some of it has merit, and some not so much, as there is not one answer for all that applies. If you are a low power user, it can be great if you have enough solar, if you use 200+ah per day as some do, you need other charging sources more than solar.

The one thing that is not normally considered with solar when the discussions turn to how much you should have, is if there is enough capacity to recover your usage, on average over good and bad days in conjunction with battery capacity actually available when you start the stay (could be full, or not, and also how deep you are willing to take the batteries). You also need to evaluate how much you drive and how much power you can get from the van charging system, which has been discussed a lot lately, and very important as you can recover usage fast than with solar, but not top off the batteries past 70-80% very well. The big benefit with solar is that it can do the long slow slog of the finish charging the lead acid batteries need once the major amount of charge has been replaced by other methods. In a typical van with something like 80 amps available from the engine and 220ah of batteries, you would still need to run the engine an hour nearly every day to recover usage only, so the solar can reduce that time. An overlooked big benefit in solar is the extending of time off grid, not necessarily being able to stay off grid indefinitely.

Our usage is similar to Pheobe3's, and we found that even 200 watts of solar was not quite enough to cover most of he conditions we see. 300 watts is much better as we can get two days of recovery in one good sun day most of the time so it averages out well. It is also enough to top off even 440ah of AGM batteries the last 20% in one day of charging after a quick capacity recovery by other methods. We tend to like to stay in one place substantially longer times than most B campers, and 5-7 or longer stays are very common for us, that is one of the reasons we have the big battery bank and high capacity charging systems so we can catch up when we do charge. Shorter stays would allow less battery capacity, smaller chargers for the engine and shore, but not less solar capacity.

One thing is the issue of how to know how much power you are using a day when solar messes up just reading your battery monitor to see. What you actually use per day will be the use from the batteries per the monitor, plus whatever the solar generates in the same 24 hours, so you need to get the solar output and add it on. It also makes some difference if the solar power was used to run things directly during the day, or if it went to charge the batteries, which wastes some of the power, so good to charge things during the day rather than at night. You hear it said that "solar doesn't actually run anything", which I would not consider that to be really the case, as the battery is just there for voltage stability when the solar is running at above battery voltage, so the solar is running everything at that point, directly from it's controller.

[BBQ]

Originally Posted by Phoebe3

A second panel was an option on this model from Coachmen, but we bought off the lot. I don't know where they would put the second panel, but I have to assume there is space for one...

Yes, we start with a full battery (actually, two 105 AH wet cells), but since it isn't getting charged at night, naturally, it depletes. How much depends on how much dark there is (it appears as long as there is sun, the panel provides enough power to keep the refrigerator running without depleting the battery). In the winter, there is a longer period without sun and we also use the lights more.

So... the refrigerator uses 4.5 AH when it is running and the amount it runs depends on ambient temperature. I would guess 33% of the time, on average. That means it uses an average of 1.5 AH per hour so it depletes the batteries about 18 AH overnight. We have 205 AH to play with. The solar panel probably generates about 25-30 AH per day. Midday charging indicates about 3.5 AH.

So the single panel generates almost enough juice during the day to run the refrigerator AND top off the batteries.

Or, you know, we could just run the engine for, like, five minutes.

Well... you have approx 100AH to play with, because for battery longevity you should not discharge them below 50% on a regular basis.

At whatever rate, 100AH net should tide you over for more than a day. There is something not right -- either the batteries are damaged, or you have some phantom draw that you are not aware of.

Maybe the batteries were not fully charged at the beginning of the evening?
Don't look at the Zamp panel... it shows the charging amp, not the battery state.

Those wetcells are pretty tough. Even if they are damaged, you can get them revived with a smart charger (desulphate).


Adding the second panel is easy. You can use 3M VHB tape to mount it. No drilling.


ps. sorry we are hijacking the op's thread.

[GeorgeRa]

I have 230Ah AGMs, 300W solar, 85l/3CuF Danfoss fridge, Espar D2 & D5 - 2-4 days without solar, with solar camping limited by other factors.Doing the conversion over again I would likely increase battery capacities to 300 to 400 Ampers , OK, Ah.

It was back in the eighties when I heard the Audi R@D manager visiting US answering a local reporter question: “Why did you pick 5 cylinders engines?” – well, because 4 was too small and 6 was too big.

[booster]

GeorgeRa is similar to our system and results, except we have about 2X the batteries and can 5-7days without solar.

[Phoebe3]

Originally Posted by BBQ

At whatever rate, 100AH net should tide you over for more than a day. There is something not right -- either the batteries are damaged, or you have some phantom draw that you are not aware of.

Adding the second panel is easy. You can use 3M VHB tape to mount it. No drilling.

I probably don't express myself well. What I meant to say was that the battery was lower in the morning than in the evening and then gets recharged via the solar panel during the day.

Booster is pretty accurate regarding our usage - probably 36 AH for the compressor fridge, 15 Ah for LED lights, 10 to run the computers, and another 5 for the water pump. If we run the Truma, the fan takes 3 or 4 per hour, so perhaps 10 AH to warm up in the morning. So, let's say 80 AH per day.

If we get sun, the panel takes that down to 50 AH. So, with one 100 w solar panel and 200 AH of batteries, we can go two days without starting the engine. One panel nearly doubles the amount of time we can stay off-grid.

[BBQ]

Originally Posted by Phoebe3

I probably don't express myself well. What I meant to say was that the battery was lower in the morning than in the evening and then gets recharged via the solar panel during the day.

Booster is pretty accurate regarding our usage - probably 36 AH for the compressor fridge, 15 Ah for LED lights, 10 to run the computers, and another 5 for the water pump. If we run the Truma, the fan takes 3 or 4 per hour, so perhaps 10 AH to warm up in the morning. So, let's say 80 AH per day.

If we get sun, the panel takes that down to 50 AH. So, with one 100 w solar panel and 200 AH of batteries, we can go two days without starting the engine. One panel nearly doubles the amount of time we can stay off-grid.

+1

Sounds all good !

[cargovanconversion]

I finished the installation of my ETFE Flexible solar panels.



You can view the latest video here

Van Williams

[medeevil]

Originally Posted by cargovanconversion

I still think that if you're not into stealth, that a rigid panel is a much better option. They're much less expensive and have a good track record.

Van Williams

I have subscribed as your a Van Master

[medeevil]

Originally Posted by cargovanconversion

I really don't know whether it will work for me. It's still a bit of a gamble. Preliminary tests show a good performance, but we'll have to wait and see.
Main reason is their stealthiness. Have waited years, but didn't want to buy the 'first generation' of flexible panels. Too many issues. These seem to be a lot better. I'll keep posting on their performance or issues that I may have.

Van Williams

going to do it based on the confidience I got from you