Hyundai vs LG vs Sunpower

[hansrx7]

Hello,

I am considering solar at my House in San Diego. I got a couple of quotes from some reputable installers for a 6.5kW system:

1. Solar Panels: Sunpower E20 327W
Inverters : Sunpower built-in micro inverters
Cost: $3.35/W
Warranty: 25 years on panels and Inverters

2. Solar Panels: Hyundai HIS-S290RG-BF
Inverters : SolarEdge - SE7600A-US
Cost: $2.9/W
Warranty: 25 yrs on panel/12 yrs on inverter


I am in the proess of getting another quote on LG panels and I am estimating they will come somewhere arounf $3/kW. My instinct is to go with Hyundai panels due to cost but I do unsderstand that they offer lower effeciency in the long runcompared to Sunpower. My questions are:

- Any feedback on Hyundai panels?
- Are sunpower panels worth the higher cost?
- Is warranty and effeciency is a real concern? Sunpwoer apparently offer warranty on service too (whereas LG and Hyundai do not)
- Do microinverters offer any real advantage over Solaredge inverters apart from aesthetics (no panel for microinverters)?

Thank you in advance!

[ButchDeal]

Those prices are $/w not $/kw unless you managed to get the worlds best deal ever.

also you didn't mention the size of the two options #1 and #2. If they are the same size or close then #2 is far better. If #1 is larger then the difference becomes a bet less clear, is the extra production worth the extra cost?

[max2k]

Hello,

I am considering solar at my House in San Diego. I got a couple of quotes from some reputable installers for a 6.5kW system:

1. Solar Panels: Sunpower E20 327W
Inverters : Sunpower built-in micro inverters
Cost: $3.35/W
Warranty: 25 years on panels and Inverters

2. Solar Panels: Hyundai HIS-S290RG-BF
Inverters : SolarEdge - SE7600A-US
Cost: $2.9/W
Warranty: 25 yrs on panel/12 yrs on inverter


I am in the proess of getting another quote on LG panels and I am estimating they will come somewhere arounf $3/kW. My instinct is to go with Hyundai panels due to cost but I do unsderstand that they offer lower effeciency in the long runcompared to Sunpower. My questions are:

- Any feedback on Hyundai panels?
- Are sunpower panels worth the higher cost?
- Is warranty and effeciency is a real concern? Sunpwoer apparently offer warranty on service too (whereas LG and Hyundai do not)
- Do microinverters offer any real advantage over Solaredge inverters apart from aesthetics (no panel for microinverters)?

Thank you in advance!

if you don't have shading I'd consider variant with string inverter.

[J.P.M.]

The annual output from equal size arrays in the same location and service is pretty much independent of which panel is used. All 5 kW panels, for example, using either Hyundai or Sunpower, or any other quality panel for that matter, in the same location and orientation, will produce about equal annual output. Don't believe me ? Check PVOutput for arrays close to one another geographically with similar array orientations.

As for warranty, panels very small failure rate (so far ~ 10 years on) seems to be mostly confined to infant mortality. All panel's warranties cover such situations.

So, the question that might better be asked is : Besides the idea that it takes up less room on a roof, why spend extra for Sunpower when no real or measurable benefit will result ? Seriously.

Sunpower's good stuff, but for the large upfront price premium, using Sunpower doesn't get anyone (except the maybe the vendor) anything more for the extra $$ except bragging rights, but they don't know it. Drink the Sunpower Kool-Aid if you wish and know you're paying more than you're getting and leaving money on the table.

[emartin00]

if you don't have shading I'd consider variant with string inverter.

Most installers are moving away from standard string inverters these days. Microinverters or optimizers are a much easier way to comply with rapid shutdown requirements.

[max2k]

Most installers are moving away from standard string inverters these days. Microinverters or optimizers are a much easier way to comply with rapid shutdown requirements.

for installers ... After they leave and take their money what happens when those micros start to fail? Who is going to climb the roof to replace them and at what cost?

I deliberately didn't mention optimizers here as they seem to be more reliable in that sense based on the messages on this board. SE inverters seem to have problems from time to time but it was hard to tell if it was just 'infant mortality' / installation error / much larger installation base or something else.

My point still remains- central inverter produces simplest possible system even with RSS included theoretically leading to less maintenance.

[J.P.M.]

for installers ... After they leave and take their money what happens when those micros start to fail? Who is going to climb the roof to replace them and at what cost?

I deliberately didn't mention optimizers here as they seem to be more reliable in that sense based on the messages on this board. SE inverters seem to have problems from time to time but it was hard to tell if it was just 'infant mortality' / installation error / much larger installation base or something else.

My point still remains- central inverter produces simplest possible system even with RSS included theoretically leading to less maintenance.

+1. With no shade, string inverters, to me anyway, seem a better concept in terms of design, maint. and reliability, if only because there are fewer failure points - generally 1 string inverter per array - rather than 1 micro per panel. And anyway, outside of some added cost, provided it's done correctly, what's so bad about rapid shutdown ?

If I was still a peddler, I'd be using rapid shutdown requirements and mandates as a red herring excuse and price it very high to make it easier to shift customers to micros that are easier to install and less expensive to obtain. Then, when micros started failing, or any other micro problems, the vendor could easily say: "Well, Mr. Phanork, as you may recall, I suggest a string inverter, but you insisted on micros after you found out a sting inverter would cost $X more because of the big, bad big brother rapid shutdown requirements that impacted cost in a very bad way. My hands were tied", or some such bogus crap.

[max2k]

+1. With no shade, string inverters, to me anyway, seem a better concept in terms of design, maint. and reliability, if only because there are fewer failure points - generally 1 string inverter per array - rather than 1 micro per panel. And anyway, outside of some added cost, provided it's done correctly, what's so bad about rapid shutdown ?

RSS is still an extra element in the power path and carries about $350-$400 price tag in parts. In case of SMA it is simply remotely controlled extra switch in the power path powered from the solar itself. SMA system can be used with any other central inverter as it is not integrated with inverter in any way. It has its own 12V power supply inside roof box which powers its own electronics and 'remote controller'- small wall mounted box with buttons & LEDs. As a result the wiring to the remote controller is 12V and low current so any cable rated for outside meets the NEC requirements. Single SMA RSS box can control up to 2 independent strings if they go into different MPPT inputs of the same inverter.

If I was still a peddler, I'd be using rapid shutdown requirements and mandates as a red herring excuse and price it very high to make it easier to shift customers to micros that are easier to install and less expensive to obtain. Then, when micros started failing, or any other micro problems, the vendor could easily say: "Well, Mr. Phanork, as you may recall, I suggest a string inverter, but you insisted on micros after you found out a sting inverter would cost $X more because of the big, bad big brother rapid shutdown requirements that impacted cost in a very bad way. My hands were tied", or some such bogus crap.

you are good BTW, it provides follow up employment to the company as well, future proofing their business: just installing solar is working on the shrinking market but if you got big enough customer base you could live off the maintenance. From this point of view there's no reason for installer to use most reliable design/components- just 'reliable enough' so to visit their customers once a year or so.

[ButchDeal]

RSS is still an extra element in the power path and carries about $350-$400 price tag in parts. In case of SMA it is simply remotely controlled extra switch in the power path powered from the solar itself. SMA system can be used with any other central inverter as it is not integrated with inverter in any way. It has its own 12V power supply inside roof box which powers its own electronics and 'remote controller'- small wall mounted box with buttons & LEDs. As a result the wiring to the remote controller is 12V and low current so any cable rated for outside meets the NEC requirements. Single SMA RSS box can control up to 2 independent strings if they go into different MPPT inputs of the same inverter.

That does not fully meet NEC 2017 RSS though, and only shuts down the conductors leaving the array.
Primarily why SMA purchased tigo optimizers is to fully meet NEC 2017.

[max2k]

That does not fully meet NEC 2017 RSS though, and only shuts down the conductors leaving the array.
Primarily why SMA purchased tigo optimizers is to fully meet NEC 2017.

correct, it depends on location. Orange County CA is still on 2008 NEC. When they switch to 2017 only new installations or major changes to the existing installations requiring new permits will be subject to 2017 requirements.

[sensij]

correct, it depends on location. Orange County CA is still on 2008 NEC. When they switch to 2017 only new installations or major changes to the existing installations requiring new permits will be subject to 2017 requirements.

Huh? Orange County's code page suggests they adopted NEC, 2014 edition.

[J.P.M.]

you are good BTW, it provides follow up employment to the company as well, future proofing their business: just installing solar is working on the shrinking market but if you got big enough customer base you could live off the maintenance. From this point of view there's no reason for installer to use most reliable design/components- just 'reliable enough' so to visit their customers once a year or so.

Well, good is a relative term and a long, boring story. If you mean good in the sense I've seen/learned enough from 10 + yrs. in a prior iteration of life as a peddler before re-education (and a pay cut BTW) to engineering to know some tricks and be able to think outside the box on ways to spot opportunity to game a system, so be it. But, part of the trick of peddling is keep your integrity while not becoming a complete cynic about humanity. That's always a work in progress.

[Mike90250]

Most installers are moving away from standard string inverters these days. Microinverters or optimizers are a much easier way to comply with rapid shutdown requirements.

Cheap and easy for them, they are not going to be around in 3 years when repairs are needed. The middle panels run the hottest, and those are the modules that will fail first, so you have to remove 2 or 3 panels to get to the dead unit. Any original savings is now lost.
Not a good idea in the long term.

[max2k]

Huh? Orange County's code page suggests they adopted NEC, 2014 edition.

my bad, thanks for correction. The point I was trying to make- it is not subject to 2017 RSS requirements yet.

[emartin00]

No one is subject to 2017 RSS requirements yet. The requirements don't take effect until 2019, even if you have adopted the latest code.