grid tie vs non GT panels

shockman

Before I rush out and buy panels I should know what I'm buying. So I read that GT panels are cheapest per watt, what is the difference between GT and regular 24V panels?? Is wireing the same + & - wires? I think I read that voltage may be slightly different but should be okay through Classic 150?

inetdog

Re: grid tie vs non GT panels

shockman wrote: »

Before I rush out and buy panels I should know what I'm buying. So I read that GT panels are cheapest per watt, what is the difference between GT and regular 24V panels?? Is wireing the same + & - wires? I think I read that voltage may be slightly different but should be okay through Classic 150?

For use with batteries, *when using a PWM CC* you need to have the panel voltage closely proportional to the battery voltage, 18V Vmp for a 12 volt battery, 36 for a 24 volt, etc.
When you use a Grid tie inverter OR an MPPT type CC for batteries, you can use much higher panel voltages and can put together a larger, easier to install panel to be used in several series strings in an array to make up the power you want.
Since the panels are larger, and there is a higher volume market for them, the price per watt is lower. Since you use an MPPT CC like the Classic, you are free to go for whatever gives your the combination of price per watt and reliability you are looking for.

niel

Re: grid tie vs non GT panels

shockman,
you can recognize a standard pv by the number of cells in the module. for a 12v pv it usually consists of 36 cells in series. for other multiples of 12v just scale it by the 36 cells per 12v. this corresponds to 72 cells in series for 24v and 144 cells in series for 48v.

most of your gt pvs these days are using 60 cells per module, but this can change as it pertains to how many cells they can fit into a pv and still be a workable size physically.

Cariboocoot

Re: grid tie vs non GT panels

Or in the short form:

Standard panels have a Vmp of either 17.5 +/- 1 Volt (12 Volt) or 35 (24 Volt) +/- 2 Volts.
"Grid tie" panels will have Vmp outside of that range such as 26 or 30 +/- 1 or 2 Volts.

To use GT panels with battery-based systems you need to use an MPPT type charge controller, or else sacrifice a fairly sizable amount of power.

shockman

Re: grid tie vs non GT panels

is the hook-up the same?? thought I read something about inverters if that the right word?? not meaning the one at batts.

NorthGuy

Re: grid tie vs non GT panels

It is the same hookup with MPPT controller. Your strings should be sized properly.

When I was buying panels, I came accross the panels by Canadian Solar which were marked "grid-tie". I couldn't find any difference, but I thought that the warranty may be void if installed "off grid" because this is not an intended use. I sent an email to Canadian Solar asking them to confirm that the warranty is valid for "off grid" installation. They sent me a long response, but didn't really confirm that they will honor the warranty in this case. So, I ended up buying different panels.

Cariboocoot

Re: grid tie vs non GT panels

shockman wrote: »

is the hook-up the same?? thought I read something about inverters if that the right word?? not meaning the one at batts.

Panels don't care what you connect them to. The cells they're made of are the same. MC4 connectors are the same. Positive and negative are the same. There is no real designation difference in fact: you could use "off grid" panels on a GT inverter.

We just call them "grid tie" panels because of the off-ideal-for-battery Vmp.

A central GT inverter will run a string of twelve to sixteen 30 Vmp panels and get its 360 to 480 Volts from that. At the high end the Voc may exceed the 600 Volts max, especially in cold temps.
The same inverter utilizing "24 Volt off-grid panels" would be limited to thirteen due to the higher Voc reaching the 600 Volt limit sooner.

shockman

Re: grid tie vs non GT panels

The best advertised price I've seen in western ca. is about $1.10 per watt, but nowhere on the discription does it say a brand or where it's made, making me a little leary, also they did have Caadian Solar panels at about the same price?? How often is warranty required on panels??? Any suggestions where to purchase in western Can. and brands???

Cariboocoot

Re: grid tie vs non GT panels

"No name" panels tend to be "iffy". As in "if you're lucky they'll last".

"Canadian Solar" panels, btw, are Chinese like 90% of them.

You're right about prices: we pay through the nose here. I have yet to find any supplier in B.C. that is reasonable. Around the Vancouver area things are slightly better, but we end up paying shipping anyway ...

If you're buying a lot it may be worth getting them out of The States. Haven't bought any myself for a long time; not sure how much trouble/taxes it is to get them in. "Go green" the politicians scream at us, but when you try .... your green all goes to them.

As for needing warranty service, that's almost unheard of these days. Really the production techniques seem to have improved greatly and panel failure almost never happens. I wouldn't worry about it. Considering how low the prices are compared to then it's practically insignificant even if one should fail; you could probably replace it outright for less money than it would take to get the warranty service done.

Oh and before anyone suggests it: Kamloops is not a matter of "nipping across the border to the U.S." okay? Believe me; it's a couple of dedicated days of travel to do that!

NorthGuy

Re: grid tie vs non GT panels

shockman wrote: »

The best advertised price I've seen in western ca. is about $1.10 per watt, but nowhere on the discription does it say a brand or where it's made, making me a little leary, also they did have Caadian Solar panels at about the same price?? How often is warranty required on panels??? Any suggestions where to purchase in western Can. and brands???

You don't have to buy locally. I bought from Evolvegreen.ca. I contacted them (and about a dozen of other sellers) and they gave me the best deal.

There are lots of sellers in Ontario. If they've got panels that do not qualify for MicroFIT program, they may sell them really cheap.

Rybren

Re: grid tie vs non GT panels

Another option is to buy used panels. Kijiji and similar services often have listings for panels. I picked up 4 210W "grid-tie" panels for $0.60/W from a guy who was upgrading his grid-tie system to larger panels. They had seen less than 18 months of service and he transfered the remainder of the 25year warranty to me. Plus, I picked them up so no shipping fees.

Cariboocoot

Re: grid tie vs non GT panels

Gee, I thought I might have to delete that link as being in conflict with our no advertising NAWS competition policy but after seeing their prices they clearly are not competition.

Evolve Green's price for 240 Watt Conergy panel: $420 ($1.75 per Watt)
NAWS price for 245 Watt Conergy panel: $222.95 ($0.91 per Watt)

See what I mean?
We really get ripped here in the Great White North.

Rybren

Re: grid tie vs non GT panels

There is a place in Montreal that carries Canadian Solar 230W panels for $260. Don't know what shipping to Kamloops would be or whether I can (or should) post a link.

NorthGuy

Re: grid tie vs non GT panels

Cariboocoot wrote: »

Gee, I thought I might have to delete that link as being in conflict with our no advertising NAWS competition policy.

I'm sorry. I didn't know that. I'll try not to put in competing links. Although, NAWS prices are usually the best. When I try to figure a fair price for something, I go to NAWS.

BTW: Anyone tried to buy something from NAWS to Canada? They have a good price for XW MPPT80-600. Is that feasible to order it, or do I get ripped off by shipping companies and custom brokers?

Cariboocoot wrote: »

We really get ripped here in the Great White North.

I think that when Canadian dollar was going down, prices grew to compensate for the difference, but when it came back up, they just stayed there.

shockman

Re: grid tie vs non GT panels

Shipping panels across the country can be quite expensive! large and light, for me Alberta or B.C. would be areas of choice

Cariboocoot

Re: grid tie vs non GT panels

NorthGuy wrote: »

I'm sorry. I didn't know that. I'll try not to put in competing links. Although, NAWS prices are usually the best. When I try to figure a fair price for something, I go to NAWS.

That was sort of a joke: we have quite a bit of flexibility on the advertising policy. Mostly we don't want people pretending to be forum members and linking up businesses (whether solar related or not). Thread relevant product/outlet links by members is okay. We just try to keep the spam out. You wouldn't believe the volume of spam that gets stopped before it gets seen.

BTW: Anyone tried to buy something from NAWS to Canada? They have a good price for XW MPPT80-600. Is that feasible to order it, or do I get ripped off by shipping companies and custom brokers?

It never hurts to call and ask them directly. The biggest problem with getting things into Canada is customs brokering as you probably know. United Parcel Service are notorious in this respect: their fees and applicable taxes can easily exceed the value of the goods. Postal service is actually much better, but they have limits in size and weight. Panels inevitably will be truck shipped, and that costs. I used to get things moved within CA via Greyhound, but that's now gone up in price a lot too (fuel costs they say). Ask NAWS; they may be able to give you an accurate quote. Some of this stuff is supposed to be duty free, but the border people don't seem to know that.

I think that when Canadian dollar was going down, prices grew to compensate for the difference, but when it came back up, they just stayed there.

Yup. Like the price of everything else in Canada; excelsior!

shockman

Re: grid tie vs non GT panels

NorthGuy wrote: »

I'm sorry. I didn't know that. I'll try not to put in competing links. Although, NAWS prices are usually the best. When I try to figure a fair price for something, I go to NAWS.

BTW: Anyone tried to buy something from NAWS to Canada? They have a good price for XW MPPT80-600. Is that feasible to order it, or do I get ripped off by shipping companies and custom brokers?



I think that when Canadian dollar was going down, prices grew to compensate for the difference, but when it came back up, they just stayed there.

I've purchased several times from NAWS and found that if shipped USPS end result is very favourable. I ship alot of stuff from US and have figured out the ins and outs. DO NOT ship anything that is not made in North America as you will pay duty and that can hurt. Anything that does not get duty applied shipped USPS will have a flat rate (like $14.95) charge for brokerage and applicable taxes applied when you receive. My last order from NAWS I shipped UPS, which I swore a long time ago I would never DO. On the invoice USPS was $65 ish and UPS was $35ish ($300 order) so I thought Hey! I got $30 for the hose job for brokerage. Well they got me! brokerage was $57.00 + tax on that amount. Most US companys will ship courrier (UPS) if not told different.

westbranch

Re: grid tie vs non GT panels

Ya, you have to keep the parcel size down. I just got a $113.37 bill for broker fee ($63:grr) and taxes (no Duty) to get a Classic via UPS from MidNite's factory. Have to wait for actual shipping cost.

MN checked USPS and it was over $100 just for the shipping due to the size, so when the weight / size gets too big UPS is less expensive.
Also USPS have a max size for regular mail and a parcel can be by slow boat via China, WAIT we are on the same continent...

Cariboocoot

Re: grid tie vs non GT panels

westbranch wrote: »

Also USPS have a max size for regular mail and a parcel can be by slow boat via China, WAIT we are on the same continent...

Yep. With that wonderful North American Free Trade Agreement which eliminates all cross-border duties, taxes, and fees. Uh ... wait a minute ...

icarus

Re: grid tie vs non GT panels

I usually have stuff shipped to a location just at the border, then try to figure out who is going down when. Pain in the neck when UN a hurry, but most of us up north have enough contact with enough people who cross often enough to make it work pretty well. I know there re drop ship places in US border towns that specialize in this stuff.

We use a spot on the Ontario/Minnesota border. They charge $3-5 a package, ~$20 for a pallet. Someone told me they averqge 3000 packages per day! When we cross we simply declare what we have, pay the HST and off we go. Depending on the value and how long folks have been in the states there may be no HST all.

Tony

Tony

Rybren

Re: grid tie vs non GT panels

westbranch wrote: »

Ya, you have to keep the parcel size down. I just got a $113.37 bill for broker fee ($63:grr) and taxes (no Duty) to get a Classic via UPS from MidNite's factory. Have to wait for actual shipping cost...

....MN checked USPS and it was over $100 just for the shipping due to the size

Yikes! Ryan had said that it would be about $40 to ship mine to Ottawa via USPS. I was supposed to be in Chicago next week and had made arrangements to have them ship it to my hotel, but my conference was cancelled so I told them to ship it here via USPS.

I don't think that they've actually shipped it yet, so I just sent them an email asking them to ship it to a UPS store in upstate NY. Don't know why I didn't think of that right off the bat. I recently ordered an epanel and have it going to the UPS store as well. (it was $145 via USPS to Ottawa)

The store charges $5.00 per delivery and if you don't pick it up within a week, it's $5/week until you do.

NorthGuy

Re: grid tie vs non GT panels

icarus wrote: »

I usually have stuff shipped to a location just at the border, then try to figure out who is going down when. Pain in the neck when UN a hurry, but most of us up north have enough contact with enough people who cross often enough to make it work pretty well. I know there re drop ship places in US border towns that specialize in this stuff.

Good thing if you live close to the border. No way I can drive back and forth in one day.

Cariboocoot

Re: grid tie vs non GT panels

NorthGuy wrote: »

Good thing if you live close to the border. No way I can drive back and forth in one day.

Me neither. I can get to the border in one day. Then take another day to get across the border ....

(The wait times can be horrific at the BC crossings.)

inetdog

Re: grid tie vs non GT panels

westbranch wrote: »

Ya, you have to keep the parcel size down. I just got a $113.37 bill for broker fee ($63:grr) and taxes (no Duty) to get a Classic via UPS from MidNite's factory. Have to wait for actual shipping cost.
MN checked USPS and it was over $100 just for the shipping due to the size, so when the weight / size gets too big UPS is less expensive.

Sure it was $100 for shipping only?
MN may not have taken into account that the USPS quote included the broker's fee (although not the taxes.)?
I imagine they do it often enough to get it right though. :-)

westbranch

Re: grid tie vs non GT panels

Just did a look-up of USPS and parcel (Classic) is $83.55 plus Insurance and what ever the sender charges for filling out the form and taking it to the USPS office (Or do they pickup?) $83.55 + $4 + $42.81 (HST) = $130.36 minimum

UPS freight est. ~$44.... plus the $ 113 = $157