Choosing Kyocera 250 watt or 320 watt panels

[MineExplorer]

I'm about to have a new 7kW (DC) system installed at my house. The original bid was with 22 Kyocera KD320GX 320 watt panels. However, the installer is having trouble getting them and wants to use 28 Kyocera KD250GX 250 watt panels instead. The footprint would end up about the same but I'm inclined to wait and have less points of failure with fewer panels. The downside is another months electric bill (or more).

If anyone has any feedback on this I'd love to hear it.

Thanks!

[Naptown]

is the cost the same?

[MineExplorer]

My cost would be the same.

[Ian S]

It might depend to some extent on your electric rate structure. In areas where you have high usage in the summer months and depend on net metering (with a December annual trueup) to build up credits prior to the summer heat, then the sooner you get up and running, the better. Because my Phoenix system was delayed from December to the following May, I lost hundreds of $$ that I probably won't ever recoup.

To be honest, I see little point in waiting for the bigger panels except for that system being a tad larger power wise.

[Volusiano]

You may have a better chance to find another compatible 250W panel from another brand if you ever need to replace one later but Kyocera don't make them anymore, than to find another compatible 320W panel from another brand.

[J.P.M.]

I'm about to have a new 7kW (DC) system installed at my house. The original bid was with 22 Kyocera KD320GX 320 watt panels. However, the installer is having trouble getting them and wants to use 28 Kyocera KD250GX 250 watt panels instead. The footprint would end up about the same but I'm inclined to wait and have less points of failure with fewer panels. The downside is another months electric bill (or more).

If anyone has any feedback on this I'd love to hear it.

Thanks!

Some things to perhaps think about:

1.) Is one or the other or both panels being discontinued ? May be that if one of either size panel failed in the future, say 10-20 yrs., they'd both be hard to find, making selection based on replacement availability something of a moot point . Panel failure does not seem to be super big on most folks radar, but the track record is still a bit short on all/most of this stuff.

2.) String or micro on the 250's ? String on the 320's ? 22 seems kind of a funky #. 2 strings of 11 320's or something else depending on inverter type/setup ?? Micros or 4 strings of 7 on the 250's sounds more common maybe.

3.) Areas/layout will be a bit different. I'd check dimensions to be sure.

4.) The system w/ the 250's is just a bit smaller area wise (~ 5.0% ) and rating (~ 0.6%), but is about a 4% more efficient on a per area basis than the one w/ the 320's, all else being about equal. The labor and some material will likely be a bit more for the 250's, but if same price to you not to worry. The 250's published eff. at S.T.C. is a bit more than the 320's. The yearly output will probably be close either way if done well.

5.) I'd make sure everything is 1st quality and not sloppy seconds or closeouts, but I'd check for that anyway. Nothing wrong w/closeouts as long as Q.C. is intact and history/status disclosed to end user up front. May be a price consideration however.

6.) Est. how long is the wait for the 320's ? 4 weeks will have less impact on cost effectiveness than 4 months, especially if a warm climate and A/C / elec. bills go up.

[MineExplorer]

I've had a 40kW system with BP panels on my commercial building since 2003. We've had quite a few panels fail so that probably makes me a little sensitive. On the other hand, BP had an acknowledged diode issue with those panels and it's unlikely I'll run into something similar with Kyocera. The 250 watt panels are "standard" in size while the 320 watt panels are not. That could have a significant impact on future panel replacement. The system will use a SMA Sunny Boy 6000TL inverter (which supports up to six strings).

My cost for the system is the same either way and the layout is very similar. I'm using a reputable installer and all the components are new (no seconds, closeouts, blems, etc.).

The wait time could be a month or two versus having the system installed next week.

I'm starting to lean more towards the 250 watt panels at this point. I'll decide on Monday when they send me a revised layout.

Thanks for all the feedback!

[silversaver]

I've had a 40kW system with BP panels on my commercial building since 2003. We've had quite a few panels fail so that probably makes me a little sensitive. On the other hand, BP had an acknowledged diode issue with those panels and it's unlikely I'll run into something similar with Kyocera. The 250 watt panels are "standard" in size while the 320 watt panels are not. That could have a significant impact on future panel replacement. The system will use a SMA Sunny Boy 6000TL inverter (which supports up to six strings).

My cost for the system is the same either way and the layout is very similar. I'm using a reputable installer and all the components are new (no seconds, closeouts, blems, etc.).

The wait time could be a month or two versus having the system installed next week.

I'm starting to lean more towards the 250 watt panels at this point. I'll decide on Monday when they send me a revised layout.

Thanks for all the feedback!

Yes, the SMA 6000TL can handle up to 6 strings at combiner box but you can only run 2 strings of 14 panels. If you are placing all 28 panels on the same roof then you are fine.

[Solarsolutions]

Install 320 watt panel if its same price.

I don't really understand how it could be the same price. It was such a shocker I asked our local solar installers if this is possible and i was surprised because everyone said it couldn't be. 320 watt should be more expensive. if its same price, make sure the panels are new not used. make sure warranty is covered in full.

Harry
California Solar Solutions

[mod note - put your biz link into your profile as your home page, not in your .sig]

[J.P.M.]

I don't really understand how it could be the same price. It was such a shocker I asked our local solar installers if this is possible and i was surprised because everyone said it couldn't be. 320 watt should be more expensive. if its same price, make sure the panels are new not used. make sure warranty is covered in full.

Harry
California Solar Solutions
mod note - link removed

FYI:

1.) CSI SD-18450: 11/15/2013, 34 ea. KD250GX. 2 inverters, $3.59/Watt to the vendor.

2.) CSI-SD-20130: 01/14/2014, 22 ea. KD320GX. 2 inverters. $3.57/Watt to the vendor.

A real shocker.

Check the CSI database.

I wouldn't be surprised if #2 above is OP.

BTW: Same vendor. Search took about 5 min.

[Volusiano]

I don't really understand how it could be the same price. It was such a shocker I asked our local solar installers if this is possible and i was surprised because everyone said it couldn't be. 320 watt should be more expensive. if its same price, make sure the panels are new not used. make sure warranty is covered in full.

Harry
California Solar Solutions

[mod note - put your biz link into your profile as your home page, not in your .sig]

OP never said it was the same price panel per panel. If you read carefully, you'll notice that the OP was talking about 22 of the 320W vs 28 of the 250W -> there are 6 MORE of the 250W. OP is talking about the same TOTAL price.

[MineExplorer]

Correct.

OP never said it was the same price panel per panel. If you read carefully, you'll notice that the OP was talking about 22 of the 320W vs 28 of the 250W -> there are 6 MORE of the 250W. OP is talking about the same TOTAL price.