[RE-wrenches] PV Powered vs SMA

[Hans Frederickson]

Nice thread... inverter pros/cons is something I spend a fair amount of time
pondering, since they are the weak link in the grid-direct installation.

Overall, I like them both (PVP and SMA).

Performance: On page 44 of the Dec/Jan issue of SolarPro, there is a list of
specifications for grid-direct inverters. Current PVP and SMA inverters have
similar CEC weighted efficiency ratings. Some of the older PVP inverter
models (1100, 2000, 2800, 3000) have slightly lower efficiency.
 
Reliability: I like that the PVP inverters have no moving parts, whereas the
SMA inverters use a fan to assist with the cooling. PV Powered does a lot of
marketing around their reliability efforts, for whatever that's worth.

Customer Service: I have not needed to utilize PV Powered customer service.
I've found SMA customer service techs to be easy to reach and knowledgeable.

Other issues: I like that PV Powered inverters are made in the USA. I also
find the hardware and manuals to be easier to work with, most likely because
they're produced in the USA for our market. The PVP inverters ship with a
full-size mounting template which comes in handy, especially when planning
the rough-in wiring and support framing during new construction.

I have a preference for the PVP inverters, and use SMA occasionally if it's
a better design fit. I agree with Wayne Irwin's comment about the durability
of the inverters with the heavy transformer designs, as opposed to the newer
"light-weight" designs (including the newest SMA products). I just feel that
in the long run, lower counts for electronic components is a good thing. I'm
not an expert on component reliability, but I know from my somewhat limited
experience that capacitors dry up and transistors are susceptible to a
variety of failure modes. The fewer of these things, the better. Also from a
reliability standpoint, I prefer to put inverters inside in a well
ventilated area, if possible. My gut feeling is that over the long haul, any
inverter will be better off in a location that is protected from moisture
and large ambient temperature swings.

-Hans
________________________________

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Keith Cronin
Sent: Tuesday, December 01, 2009 1:04 PM
To: RE-Wrenches
Subject: [RE-wrenches] PV Powered vs SMA


Hi colleagues

Do any of you have a preference, PV Powered vs SMA in the residential space-
2k-5k grid tie inverter zone?

Comments on performance/reliability/customer service etc?

Any feedback on their monitoring vs SMA's webbox?

Thanks

Keith