SilverLeaf said:
Panels typically last 20-25 years. Inverters typically last 10-15 years. I would prefer my inverter to go in a single instance, not sporatically over time. Micro-Inverters (or Tigo Maximizers) are preferable in instances of shading or other types of obstructions. If no obstructions, no need for Micro-Inverter.
Certainly not a "need" but they have a lot of advantages. Enphase specifically is warranted for 25 years with a 100% up time guarantee. So they'll replace a failed inverter, pay to have it installed, and pay for the lost production. Will your central inverter manufacturer do that? When something does go wrong instead of your entire system going down you just loose a panel.
Even in non-shade instances. Do all the panels output the exact same amount? Do they all age at the same rate? Does soiling happen evenly? Sure we aren't talking big numbers but
Being able to see per panel statistics is amazing. Would you even know if a panel failed? What if a panel failed in a way that took out the whole array. That sure wouldn't be fun to troubleshoot.
It seems that the efficiency ratings of the microinverters are often higher.
Doing it DIY dealing only with AC makes the system sooo much easier to design and install. Probably not the case for a professional.
Central inverters can be noisy, having them somewhere where you can hear them isn't pleasant.
Central inverters are big and bulky and need somewhere to go.
When you want to add more panels in the future it's likely to be much easier with micro inverters.
When you have multiple roofs at different angles, designing a central inverter based system can get trickier.
I think it's definitely obvious that microinverters are safer. With central inverters you have always live (in the sun) high voltage DC going from the roof to the inverter. I hear some jurisdictions require a disconnect on the roof.
There's a lot more rules when working with DC that to me seemed more difficult to get a grasp of compared to AC.
For small arrays microinverters will be cheaper. Obviously as you get larger and larger that gap goes the other way, but if you get too large then you need two inverters and they are cheaper again.
Anyway, that's my brain dump of why I like microinverters
If the Enphase M215 wasn't available when you got your tigos I can see why you made that decision though.
pjoseph said:
No micro inverter needed as it is integrated into the panel.
What do you mean not needed? That's like saying the LEAF does't need a battery because it's integrated into the automobile?
I have never compared Solarbridge to Enpahse. Where they really selling back in late summer of 2011? If I had heard of them they didn't even make it on my radar to compare. But my gut reaction is Enphase has a lot more experience in this area.
My assessment of these "AC Panels" is they are not much to get excited about. As far as I can see the only real benefit that they MIGHT be able to offer is cheaper material cost and cheaper install cost. With Enphase you have to consider the mounting of the inverter to your rack and the grounding of the inverter. This requires a little bit of extra hardware, planning, and install time. With the "AC Panels" that part of the process is done already. I'm not seeing any technology innovation here. It's just shifting some labor from the roof to the factory.
I suspect what is going to happen though is there is going to be a premium charged for this. The other issue is you can't pick out the cheapest PV panel. You are stuck picking from the manufacturers who have signed up to integrate these.
pjoseph said:
Wondering if anyone else is familiar with an integrated design (not Enphase).
I think the question you should be really asking is anyone familiar with SolarBridge. The integrated design doesn't change anything except the process to install it. It's not even "integrated". The only difference is it's mounted to the frame of the panel instead of to the racking and done at the factory.
What was the cost difference between your three quotes?
coolfilmaker said:
It seems like the two options I have would be getting either 17 square foot inexpensive ones for about $500 or 13 square foot sunpower ones that come out this month and will likely cost a few hundred more.
That's a bizarre way to think about the cost of panels. The number I want to see is cost/DC watt rating.