1 megawatt solar power

[Searching_Ut]

beach house,


I like the way you think when it comes to your control system for your solar. I really like the way the bogart SC2030 controller trimetric system works when it comes to battery charging, which can't be beat. Managing the solar is just icing on the cake. I went with the trimetric/sc2030 system with two controllers each connected to 5 grape 100 watt solar panels. My peak output on occasion has put the controllers to a stage where they back down from 64 or so max amps to about 58. Seems they back off a bit when they go into a protection mode for overcurrent. That said, most of the time my peak output is slightly below 60 amps and you can tell the system isn't protecting itself. I generally park in shade, or partial shade which is why I went larger than most folks think necessary for 4 gc batts following having started with a 400 watt system. One of the things that has surprised me the most is how much output I get in total shade, heavy overcast, and the early morning and late evening hours. No where near the mid day reading, but significant enough to make a difference.

[beach house]

Originally Posted by Searching_Ut

beach house,


I like the way you think when it comes to your control system for your solar. I really like the way the bogart SC2030 controller trimetric system works when it comes to battery charging, which can't be beat. Managing the solar is just icing on the cake. I went with the trimetric/sc2030 system with two controllers each connected to 5 grape 100 watt solar panels. My peak output on occasion has put the controllers to a stage where they back down from 64 or so max amps to about 58. Seems they back off a bit when they go into a protection mode for overcurrent. That said, most of the time my peak output is slightly below 60 amps and you can tell the system isn't protecting itself. I generally park in shade, or partial shade which is why I went larger than most folks think necessary for 4 gc batts following having started with a 400 watt system. One of the things that has surprised me the most is how much output I get in total shade, heavy overcast, and the early morning and late evening hours. No where near the mid day reading, but significant enough to make a difference.

Searching_UT,

I fully agree with you and am experiencing the exact same things your are, including having adequate amps in shade, heavy overcast, fog and rain. And all this from a PWM system to boot! Actually, because of the size of the system, I was convinced that I needed an MPPT charge controller, but a good friend of mine, with great effort, managed to convince me to go with Bogart's setup. I was very reluctant, but finally gave in because of the redundancy (costed less too), and boy did the system ever exceed my expectations! Handy Bob was not kidding when he said that Bogart's system will outperform many MPPT controllers. I know one full timer who has 700W on his Airstream, with a MPPT controller (I can't remember, I think Renogy) that only puts out a maximum of 25 amps. Half of my system (480W) puts out 29-31 amps during peak sun. Hopefully this thread will convince him to make some changes. Also, one of the less noticeable things that also surprised me, is the controllers at full capacity are still fairly cool. You can feel the cooling fins/heat sink get warm, but you can hold your hand on the heat sink with out it feeling uncomfortable.

All in all, a big thumbs up!

[Itinerant1]

Originally Posted by beach house

Itinerant1,

I have the same panels, but only 6 of them (960W). They are wired in parallel but split up in two groups of three panels, fed into 2 Bogart Engineering SC2030 charge controllers, that are tied into and controlled by the Bogart Engineering Trimetric 2030RV battery monitor. The panels and the whole setup exceeded my expectations, considering that those are PWM controllers. The panels often exceed the amperage they are rated for. The highest output I ever seen was 63 amps. In the summer time the system consistently puts out 58-59amps. In the spring it's 52 amps. These numbers are during peak sun, around noon, give or take an hour. Per panel, our output numbers are pretty much the same, which makes sense considering we have the same panels. The one feature I do like with Bogart's setup, is it has built in redundancy. Even though the charge controllers are tied in and controlled by the Trimetric, they are still two completely separate systems. So if one controller dies, or a panel shorts out, 50% of my system will still work. If the Trimetric dies, the charge controls will still charge in basic mode.
All in all, you just can't beat silent power when you're out in the wilderness!

Thank you to all who posted your numbers! It is great to see how well your systems are performing.

It almost appears that the panel performance is very close between our systems with one being PWM and MPPT controlled.

I see many post and ask about peak performance at noon +/- when in reality I think of the performance starting when the sun hits the panels and charging starts to happen.

Today for instance in South Dakota 8am clear skies, 55f and it's already charging 30a another hour or so it will be near 50a and keep increasing fast by 10 or so it cruising along at 65a + and before noon top out near 80a +/-.
Now during this time (8am +)the fridge has been turned over to electric, computers are plugged in, Magnum inverter is always on plus misc draws so there while be 33-40a draw with the balance going into the batteries for charging. By 12-1 batteries are full and floating the rest of the day.

So if some think that solar is a scam so be it I'll take this kind of scam all day long.

[oatmeal]

Originally Posted by beach house

You also need to count in the maintenance cost and the wear and tear cost of the generator.

Aah, I figured out how to make your comments not blue. (And BTW, putting your comments within the quote makes it really hard to quote you).

Anyway, I was just pointing out that it's not real accurate to say, "I saved $15 because I have solar and could take a dry site instead of an electric one" because the same could be said by someone with a generator, who also saved $15 by taking a dry site instead of an electric one.

And at the very least, when calculating the out-of-pocket savings by selecting the dry site, you have to account for fuel used for the refrigerator and water heater (if any). And you can really get into the weeds with amortizing the cost of the equipment, and if you're talking about the effect on the environment, you have to take into account the production of the solar panels and the environmental "cost" of the batteries, which you need more of if you're taking a dry site instead of an electric one.

I'm all for simplicity, so I'm not enthusiastic about being in the weeds, but I do appreciate accuracy. Every day I boondock I know I've had to pay for about 1/2 gallon of propane for my refrigerator, and some amount for propane for my water heater if there hasn't been enough solar to be diverted to it on electric.

Originally Posted by beach house

Unless you are running a diesel, the more you load the generator, the more fuel it will swallow, especially if it is a propane fueled generator. It is much less costly to run the refrigerator and HWH propane, then to load the generator running those items. So, you don't save anything, if anything you are spending more...

Actually, my generator is a diesel; I didn't know propane generators use that much more power when loaded down.

BTW, how much propane does a water heater use? I've been able to test my refrigerator by using only the refrigerator on propane for an extended time and then refilling the propane and thereby knowing how much propane it used over that period of time. I've never been able to do it with the water heater and would love to know. I have a 10-gallon one now that needs replacing, and I think I'm going to switch to a 6-gallon one, which will be easier to fully heat when boondocking. I'd like numbers for either one, for how much propane it uses to fully heat a tank of water when it's about 70 degrees outside.

Also, if you're paying over $3/gallon for propane, you might try looking for Tractor Supply locations. Many of them have propane and can fill onboard tanks, and it's usually right around $2/gallon.

Originally Posted by McRod

My post wasnt about solar vs other forms of power generation.

But it kind of was because you didn't acknowledge that solar isn't the only way to take advantage of cheaper non-electric sites.

Again, I'm as pro-solar as a person can be, but I really do think the bottom line should be "Do I want to go solar?" and not "Is solar going to pay for itself?" because the calculations are so complex.

[babock]

I love solar and the fact that it's quiet but let's get real about the "green" aspect as it pertains to an RV. There is no way that using an RV is a very "green" activity considering how much fuel is burnt. Hardly a good way to reduce you "carbon footprint" is using an RV.

[astrocamper]

The greenest part of solar for RV is the blissful quiet of your campsite. Second is not having to deal with a fuel can to fill up your portable generator.

If you are camping where you don't need an air conditioner and you are keeping the windows open, the silence is greatly appreciated by you and your neighbors.

[beach house]

Originally Posted by Itinerant1

It almost appears that the panel performance is very close between our systems with one being PWM and MPPT controlled.

I see many post and ask about peak performance at noon +/- when in reality I think of the performance starting when the sun hits the panels and charging starts to happen.

Today for instance in South Dakota 8am clear skies, 55f and it's already charging 30a another hour or so it will be near 50a and keep increasing fast by 10 or so it cruising along at 65a + and before noon top out near 80a +/-.
Now during this time (8am +)the fridge has been turned over to electric, computers are plugged in, Magnum inverter is always on plus misc draws so there while be 33-40a draw with the balance going into the batteries for charging. By 12-1 batteries are full and floating the rest of the day.

So if some think that solar is a scam so be it I'll take this kind of scam all day long.

Intinerant1,

You make a great point, but it's hard enough to get people to post their simple peak numbers, even harder to get numbers of what they get in the mornings or during overcast/rainy days, so I just try to at least get the basic numbers to compare and know if my system is doing well, or has room for improvement. If someone numbers are really low, it's usually a sign of a poor setup or a inferior charge controller.

In the mornings, my per panel numbers also match yours, but I would guess that during pretty cold sunny days your system would be putting out more per panel, than mine. Searching_UT also has similar numbers and results as my system, but he has different brand and size panels. So it seems like one of the most important parts to setting up solar is to have a true quality controller, and the only way to know which ones are good and perform as claimed, is to share/post real life numbers. So far it seems like Bogart's charge controllers coupled with the Trimetric is in a league of its own. Way ahead of other PWM controllers and just a hair behind quality MPPT controllers like your Magnum or a Morningstar.

I fully share your sentiment regarding your last sentence!

[beach house]

Originally Posted by babock

I love solar and the fact that it's quiet but let's get real about the "green" aspect as it pertains to an RV. There is no way that using an RV is a very "green" activity considering how much fuel is burnt. Hardly a good way to reduce you "carbon footprint" is using an RV.

babock,

That statement does not apply to all RVers and gives many an unfair and bad rep. Many RVers stay stationary for two weeks or longer, then mosey on a hundred miles to a new location. Those type consume less fuel than an average person commuting to work. Now for the RVers who travel every couple of day, yup, they do go through a lot of fuel. In actuality, the ones that don't move around much and boondock, they have the smallest foot print, as they use little fuel, water, and usually have solar. Just think, how much water does an average person waste that lives in a sticks and bricks home vs a fulltimer...

[babock]

Originally Posted by beach house

babock,
That statement does not apply to all RVers and gives many an unfair and bad rep.

Agreed...it doesn't apply to all. But if you are driving a 38' motorhome or a 5th wheel driven by a 3/4T Diesel pick up, you are far from having a small carbon footprint.

[VoiceNinja]

Originally Posted by babock

But if you are driving a 38' motorhome or a 5th wheel driven by a 3/4T Diesel pick up, you are far from having a small carbon footprint.

But my neighbor says he gets 18 mpg in his 43' Diesel pusher!

(We have a 40' DP and have no illusions that we're environmentally friendly when we travel...Solar doesn't repay our Diesel fuel sins, but it also doesn't cause more CO2 sin!)

[beach house]

Originally Posted by oatmeal

Aah, I figured out how to make your comments not blue. (And BTW, putting your comments within the quote makes it really hard to quote you).

Anyway, I was just pointing out that it's not real accurate to say, "I saved $15 because I have solar and could take a dry site instead of an electric one" because the same could be said by someone with a generator, who also saved $15 by taking a dry site instead of an electric one.

And at the very least, when calculating the out-of-pocket savings by selecting the dry site, you have to account for fuel used for the refrigerator and water heater (if any). And you can really get into the weeds with amortizing the cost of the equipment, and if you're talking about the effect on the environment, you have to take into account the production of the solar panels and the environmental "cost" of the batteries, which you need more of if you're taking a dry site instead of an electric one.

I'm all for simplicity, so I'm not enthusiastic about being in the weeds, but I do appreciate accuracy. Every day I boondock I know I've had to pay for about 1/2 gallon of propane for my refrigerator, and some amount for propane for my water heater if there hasn't been enough solar to be diverted to it on electric.




Actually, my generator is a diesel; I didn't know propane generators use that much more power when loaded down.

BTW, how much propane does a water heater use? I've been able to test my refrigerator by using only the refrigerator on propane for an extended time and then refilling the propane and thereby knowing how much propane it used over that period of time. I've never been able to do it with the water heater and would love to know. I have a 10-gallon one now that needs replacing, and I think I'm going to switch to a 6-gallon one, which will be easier to fully heat when boondocking. I'd like numbers for either one, for how much propane it uses to fully heat a tank of water when it's about 70 degrees outside.

Also, if you're paying over $3/gallon for propane, you might try looking for Tractor Supply locations. Many of them have propane and can fill onboard tanks, and it's usually right around $2/gallon.


Again, I'm as pro-solar as a person can be, but I really do think the bottom line should be "Do I want to go solar?" and not "Is solar going to pay for itself?" because the calculations are so complex.

Oatmeal,

I do realize the point you were making and I agree with it, as far as the perceived $15 savings vs full hookups without counting in the propane usage and other misc things, but I don't really see where the savings is, to run a generator to save $15, with the exception of maybe some really fuel efficient small generators. It is one thing of splitting hairs on costs, but some costs are very obvious and potentially large, that often get overlooked, and the big one is the cost of generator maintenance/repair and wear and tare on the generator. If it is only occasional use, than it is irrelevant, but if it is a constant or common use, than maintenance and wear and tear can't be ignored, it would be foolish not to account for that reality.

For the record, I did not mention the environmental factor, but a few others did. Since you mentioned it, and even though I don't look at it at this angle, I have to say that lead acid batteries have been around for ages and they sure ask heck get recycled, so there is not much environmental impact as I see it, plus battery banks are on most all RVs weather they have solar or not, and since most RVers do a mix bag of boondocking and full hookups, the size of the battery bank is on the large side, and has been for quite some time. As for solar panels and the impact to create them, I don't know the exact science, but to build oil rigging, well drilling equipment and drill and extract oil, refining, and transporting the oil/fuel, etc. Not to mention environmental spills, it is probably a wash with what is involved with making solar panels. The difference is in the aftermath of usage, solar at that point is very clean, generators not so much. Unless we want to live in the dark ages, the reality is, most of anything we need in this modern lifestyle has a negative impact, so the attempted goal should at least be to have the products we need, to be at least friendly during the usage stage.

I understand the accuracy, but when there are a lot of variables, all one can do is estimate. As for how much the refrigerator uses propane, I have had a couple of friends complain that their refrigerator consumes a lot of propane. I was surprised, as mine seems to take very little. I did notice that both of their units were new Norcolds (standard/common size 7cu/ft?) and mine is a bigger (10 cu/ft) old Dometic. Maybe the burner design or nozzle size has changed, I don't know. I can say that last summer I used 37 gal in 2 months, with the refrigerator on gas the whole time, generator usage while driving, and during the last 30 days, we were using the furnace at night, every night. We were in the Rocky Mountains and it got cool at night. The funace did not run a lot, but kicked on at least twice every night for those last 30 days. It seemed like normal consumption to me, but after hearing other complaints, maybe I just have a fuel sipping refrigerator?

As for you possibly switching your HWH to a 6 gal, have you considered switching to a tankless instant hot water system. There is less water to heat, but I'm sure the burner is bigger, so I don't know if it would bring you saving, I guess it depends on how much you use it.

As far as calculating HWH consumtion? That is probably the hardest to calculate, way to many variables. Does one leave the HWH on all the time, or shut it off at night? How much hot water do they use? How big is their tank? Is it foam or fiberglass insulated? And the list just goes on.
One last note on the HWHs, not all of them run on electric, some are propane only, so this yet again adds to the campground expense variable. In short, everyone needs to assess their own needs, situation, equipment, expenses and budget, but they also can't forget that generators (especially the bigger ones), cost money to maintain, repair and replace/rebuild when they are used daily. Yes, solar involves maintenance and repairs, but those costs are much smaller.

Anyone who needs to or chooses to generate their own power needs redundancy. This means at least two power sources. For me, solar works great as a primary source with the generator as a last resort backup. Since going solar, I have only needed it to run the generator to run the a/c unit while driving in really hot weather. This gives it just enough exercise to keep it in good working order.

Thank you for the tip of TSC propane. Even though I'm aware of it and predominately use them for my propane needs, many out there are not aware of how much less their propane costs. That said, in my region, TCS price per gallon was $3.29 since last fall, it only now has finally dropped to $2.89 gal. Many other suppliers charge $1 to $2.50 more than TSC. Its a racket and I don't know how they get away with such price disparity in the same vicinity.

Yes, I agree with your last statement, even though in certain situations, it's not rocket science to figure out that the solar will pay for itself.

[rarebear.nm]

I think we in the RV life style group should be careful about splitting hairs too much about our energy use and being green. I got a large solar system more for what it allows us to do than for the carbon footprint reduction. However, any engery reduction is good. But our total environmental impact is still quite large. It’s a life style we chose. People in most of the world do not even have that choice. We are very lucky.

[oatmeal]

Originally Posted by beach house

As for how much the refrigerator uses propane, I have had a couple of friends complain that their refrigerator consumes a lot of propane. I was surprised, as mine seems to take very little. I did notice that both of their units were new Norcolds (standard/common size 7cu/ft?) and mine is a bigger (10 cu/ft) old Dometic.

I did the measuring when I had a 2002 Norcold 1200LR (the 4-door one), which I think is 12 cubic feet. It so happened that I filled and refilled my propane tank such that it was only refrigerator use during that time (or, actually, two times), 24/7 while boondocking, and it used 1/2 gallon per day. Almost every other calculation I've seen also has water heater use in the mix, so it's impossible to isolate the refrigerator use. I also had the advantage that I didn't realize I had good data until after the fact, so I didn't inadvertently modify my behavior during what turned out to be the experiment--I just lived as I usually do when boondocking.

Originally Posted by beach house

As for you possibly switching your HWH to a 6 gal, have you considered switching to a tankless instant hot water system.

I think the tankless water heaters run on propane, and since I have on onboard propane tank on a 40-foot motorhome, refilling propane is always a chore I'd rather avoid.

Also, I think the tankless heaters require a minimum amount of water to be passing through them to work, and when we're boondocking the showers are on super low flow.

Also, we modified our water heater so it can run off the batteries. Once the batteries reach "float" stage, the excess solar is diverted to the water heater, and I'm keeping that no matter what. It is often enough to fully heat the ten gallons, but it would be easier to heat six gallons. Also, when using propane, it is more efficient to heat six gallons than ten.

If water heaters had internal thermometers on them it wouldn't matter--I could merely heat the water to the desired temperature and just not mix any cold water with it. But that's not possible, so unless I've had some dumb luck, the hot water will need to be mixed with cold, and the energy used to get it hotter than it had to be is wasted. Assuming the water gets fully heated, six gallons will be more efficient than ten gallons, even though even then, if we're seriously boondocking only about a gallon or maybe two of hot water will be used. But there's only so much a person can do.

Originally Posted by beach house

As far as calculating HWH consumtion? That is probably the hardest to calculate, way to many variables. Does one leave the HWH on all the time, or shut it off at night? How much hot water do they use? How big is their tank? Is it foam or fiberglass insulated? And the list just goes on.

Actually, I don't need it to be anywhere near that complicated. I just want to know how much propane my water heater is using per unit of time when it's heating the water. Lord knows I can hear it, so it would be easy to put a stopwatch on it and just do the math.

But I want real numbers, not theoretical like propane uses X numbers of something to produce Y BTUs or whatever.

Originally Posted by beach house

Thank you for the tip of TSC propane. Even though I'm aware of it and predominately use them for my propane needs, many out there are not aware of how much less their propane costs. That said, in my region, TCS price per gallon was $3.29 since last fall, it only now has finally dropped to $2.89 gal. Many other suppliers charge $1 to $2.50 more than TSC. Its a racket and I don't know how they get away with such price disparity in the same vicinity.

Are you in the northeast? That's where I've seen some seriously high propane prices.

But I just looked at my records, and I haven't filled my tank at Tractor Supply in a while. It was $1.99 for a long time, and it's now $2.49 in the southwest. It's also $2.49 at a TSC near Denver, and at the co-op 2 miles away from there, it's $3.50.

That's one reason I find buying propane annoying--since I'm fulltiming, I don't have a known cheap local place.

Originally Posted by beach house

Yes, I agree with your last statement, even though in certain situations, it's not rocket science to figure out that the solar will pay for itself.

I had the misfortune of installing solar when it was really expensive, but that also means I've enjoyed a long payoff period. Right now I'm at 920 nights where I didn't have electrical hookups. That could be an overnight stay between campgrounds, or it could be part of a 2-week stint of boondocking, so even that number isn't exact.

A while back I came up with $5/day for fuel for the generator as a decent approximation (and I did sometimes use the generator while driving, but very rarely while stopped and never overnight). That $5/day puts my solar "savings" at $4,600.

My RV came with the required batteries and inverter, and wouldn't have been any cheaper without them. But I had to buy the panels and controller (but saved money by not paying for installation) and that totalled $5,370. (This is for 1,050 watts of panels, in 2005 and 2006, when they were expensive.) And a few years ago I had to replace the controller, so that would have to be added to the cost, but note that it wouldn't be represented if I happened to crunched the numbers right before I bought it--further muddying the waters.

So I don't think my solar has paid for itself. And the $5 may be low, but I forgot to account for propane for the refrigerator and I don't know how to account for propane for the water heater and furnace while boondocking (sometimes either or both are used even when on shore power, so total propane usage isn't accurate), so the $5 might not be too far off.

And even though I very rarely use my generator, it still requires a base level of maintenance, with oil changes and belts; no way would I be without a generator, even with a decent amount of solar.

In my case, I think it would be inaccurate to compare generator usage or wear and tear because on many of these boondocking stints, I simply wouldn't have done it if I'd had to rely on my generator. I've got a big diesel one, but I'll be honest--it's not that annoying when I'm inside, and if my only guide were the rules on generator hours, I would probably be okay with listening to it. But I also use innocent victims having to listen to it as my guide, and solar wins that one every time, and it means I stayed places I wouldn't have stayed if I hadn't had solar. I know for sure that one place I've spent many, many days would be off the table if I had to use my generator, so while those days are in my boondocking category, they simply wouldn't exist in my generator category.

When we were deciding whether to go solar, we were looking at every consideration, especially the financial one, and finally said, "If we want to do it, then do it." In retrospect, I think that really was the right way to look at it.

[Reed Cundiff]

Astrocamoer

Am with youb100% with quietude
. Wildlife and birds basically ignore your presence without a generator

As noted earlier, we have only plugged in with 5th wheel once in four years and never used generator.

Did plug into power on beach in Yucatan and again in San Miguel de Allende since our 2002 Dometic fridge was very difficult to light at night after using solar all day.