Advice on proposed equipment

[SatManager]

I prefer the Power One Micros over the Enphase. One thing Enphase has done consistantly since day one is run in the red. Power One has actually turned a profit and they are sized more correctly for the 285w panels. Enphase typically will clip around 225w. Is a string inverter an option?

They do have string inverters available from 2kw to 6kw. Power-One is being acquired by ABB so they will even have more resources.

[SoCalsolar]

I prefer the

I prefer the Power One Micros over the Enphase. One thing Enphase has done consistantly since day one is run in the red. Power One has actually turned a profit and they are sized more correctly for the 285w panels. Enphase typically will clip around 225w. Is a string inverter an option?

[SatManager]

That means very little - small differences in orientation, tilt, cleanliness, local morning mist etc can tilt the scales one way or the other.

I agree Russ, but if I didn't mention it, someone would bring it up that I didn't give all the information, so in the interest of full disclosure. The difference between my west and south facing panels for the past 30 days is less than 1 watt hour so as you pointed out, no real difference. The real factor was the wattage difference between the Power-One inverter (250w rated) and the Enphase inverter (215w rated) along with the panel wattage matching.

[russ]

Amazingly, I am monitoring a 20 panel enphase system (about 4.80kw using 240w panels) and I outproduce him most days. It is here in the Las Vegas valley like I am all panels are facing south. I have a 19 panel system, 17 facing south, 2 facing west. rated at 4.75kw. But most days by the afternoon, I am outproducing his system and total production is more.

That means very little - small differences in orientation, tilt, cleanliness, local morning mist etc can tilt the scales one way or the other.

[SatManager]

I too am having to make a decision on inverters and would like some feedback between enphase and PowerOne. I am going to use LG 285w panels (about 30), live in coastal SoCal. I don't know what the practical clipping would be on the enphase 215 and I have no idea when the 250 is coming out (which would be perfect).

Looking to sign docs next week.

Thanks for the advice for a new guy...

-jason

I have used the Power-One inverters now for the past 30 days and had one inverter fail on the system at the 10 day point but that was with the outside temps at 118 degrees helping keep things really toasty. Troubleshooting was quick and easy and they were able to replace the unit fairly quickly once a new one was received from Power-One. No other problems were seen on the other inverters so I would think that I got one that failed due to heat stress.

I am using Mage 255w panels with the 250w inverter and with perfect weather/sun conditions I have seen the power output to reach 250 - 260 watts for short periods (5 minutes or less). Power-One has the same inverter that is also rated for 300 watts that would be a closer fit for the 285 watt panel.

Amazingly, I am monitoring a 20 panel enphase system (about 4.80kw using 240w panels) and I outproduce him most days. It is here in the Las Vegas valley like I am all panels are facing south. I have a 19 panel system, 17 facing south, 2 facing west. rated at 4.75kw. But most days by the afternoon, I am outproducing his system and total production is more. At least once I got the one inverter back on line. Running on 18 made it an unfair fight. Anyway, I have been really happy with the system. We are in Monsoon season here so the daily weather isn't the continuous sun that you would expect in Las Vegas. You can see my public page: https://easyview.auroravision.net/ea...tityId=1491856

I have spoken to some of the customer service people in Phoenix about some of the monitoring capabilities and found them to be very knowledgeable and helpful. Your installer will have a great support staff available to help him if needed.

[russ]

sounds like you found the winner then.
I personally would do the Enphase as they are the oldest and most experienced of the two in this arena.
But that's just me

Naptown is saying "stick with the proven" - that is something we do in industry all the time - proven is far safer.

[jasonsc]

Inverter Decision

I too am having to make a decision on inverters and would like some feedback between enphase and PowerOne. I am going to use LG 285w panels (about 30), live in coastal SoCal. I don't know what the practical clipping would be on the enphase 215 and I have no idea when the 250 is coming out (which would be perfect).

Looking to sign docs next week.

Thanks for the advice for a new guy...

-jason

[Naptown]

I would still need to find a company that is willing to offer a string inverter system for the same price or less than what the one company is offering the micro-inverter system for. I have two companies that are at $4.00 a watt or less and everyone else is going up from there (all the way to $6.40 a watt). I can't force a company to lower the price. The company that is selling at 3.70 a watt is a very highly rated company, been in business for 15 years and is a large electrical company in the Vegas Valley with many large projects under their belt. They are the only company that has been upfront, not trying the games that some of the companies like to play with pricing, and has discussed options with me for sizing the system. That is why I decided that they would get my business. I was looking for more of everyone's thoughts in regards to the Power-One micro-inverters vs the Enphase micro-inverters.

sounds like you found the winner then.
I personally would do the Enphase as they are the oldest and most experienced of the two in this arena.
But that's just me

[SatManager]

I can understand the Sunpower being more expensive.
but you could still use the 19 panels with a string inverter and it would be cheaper. It would need to be a power 1 inverter for the two mppt inputs.
that is about a $2000 inverter cost to the contractor.
Wholesale on the enphase for 19 panels would be almost $3000.

I would still need to find a company that is willing to offer a string inverter system for the same price or less than what the one company is offering the micro-inverter system for. I have two companies that are at $4.00 a watt or less and everyone else is going up from there (all the way to $6.40 a watt). I can't force a company to lower the price. The company that is selling at 3.70 a watt is a very highly rated company, been in business for 15 years and is a large electrical company in the Vegas Valley with many large projects under their belt. They are the only company that has been upfront, not trying the games that some of the companies like to play with pricing, and has discussed options with me for sizing the system. That is why I decided that they would get my business. I was looking for more of everyone's thoughts in regards to the Power-One micro-inverters vs the Enphase micro-inverters.

[Ian S]

I can understand the Sunpower being more expensive.
but you could still use the 19 panels with a string inverter and it would be cheaper. It would need to be a power 1 inverter for the two mppt inputs.
that is about a $2000 inverter cost to the contractor.
Wholesale on the enphase for 19 panels would be almost $3000.

Actually the quote is for Power one micros. Might they be trying to muscle into the micro market by undercutting enphase?

[Naptown]

I can understand the Sunpower being more expensive.
but you could still use the 19 panels with a string inverter and it would be cheaper. It would need to be a power 1 inverter for the two mppt inputs.
that is about a $2000 inverter cost to the contractor.
Wholesale on the enphase for 19 panels would be almost $3000.

[SatManager]

Interesting. Maybe with increased competition among suppliers of micros, the prices are coming way down. What you've described looks like a decent deal so I'd say, go for it!

Thanks for the advice. I just sent him an email to schedule an appointment on Monday to sign the contract.

[Ian S]

Problem is getting a company to want to propose doing that. I had 5 companies come in and only 2 companies did string inverters. And the lowest price of those was the sun power vendor. The other came in with a quote of $32,000 for the system. The sun power vendor wanted $26,000. The 3 vendors with micro-inverters ran from the low of $17,580 to $23,000. All of the companies have very good records.

Interesting. Maybe with increased competition among suppliers of micros, the prices are coming way down. What you've described looks like a decent deal so I'd say, go for it!

[SatManager]

If you are really looking to save money, then, unless you have shading issues, a string inverter would still work. What might look undersized probably isn't and even a 5kW unit would probably not be too oversized. Fronius certainly makes units that would work for your power output. Maybe add another solar panel!

Problem is getting a company to want to propose doing that. I had 5 companies come in and only 2 companies did string inverters. And the lowest price of those was the sun power vendor. The other came in with a quote of $32,000 for the system. The sun power vendor wanted $26,000. The 3 vendors with micro-inverters ran from the low of $17,580 to $23,000. All of the companies have very good records.

[Ian S]

As you noted, from the initial price of $17,580 I would have the federal tax credit of 30%, then the annual utility bill savings of about $1,450, PEC (Production Utility Credits) payments (same as SRECS or RECS in other states) of about $500 a year. Add in inflation factors and it comes out to about the 5 year point.

Another thing that happened here in Nevada is that Nevada Power was approved by the state legislature to shut down all coal power generation plants and replace them with gas and renewable source generation plants. This is going to increase rates to (1) pay to close the coal plants, and (2) pay to build the new plants. And we better hope that natural gas prices don't head back up again as Nevada is now going to have most of its eggs in one basket (gas power generation). And to make it even better - Warren Buffett is buying Nevada Power under his Mid American brand. I think it is a good thing to get as close to 100% away from Nevada Power as I can! Makes those inflation factors above look very favorable.

And we are looking at our first day at 110 degrees. Makes that A/C work even harder.

If you are really looking to save money, then, unless you have shading issues, a string inverter would still work. What might look undersized probably isn't and even a 5kW unit would probably not be too oversized. Fronius certainly makes units that would work for your power output. Maybe add another solar panel!