Enphase Micro-Inverter

[crlare]

Greetings:

What is the opinion of the Enphase Micro-Inverter? What I understand is it is a inverter per module, connects AC outputs per module therefore eliminating the need for high voltage DC. Typically such distributed components increase costs. The ad says it provide greater efficiencies. What are the trade offs? Is this just hype?

[Bruce]

Here is a great link that I found on this website:

http://www.arttec.net/SolarPower/7_Installing_Inverters/index.htm

The guy who has this site is a member on this forum. he used enphase and writes about it.

[russ]

If I understood correctly, Mike has said many times that they look neat and may be but they are also totally new with no track record.

You pays you money and you takes yous chances whereas other types are well proven.

[Green Ying Yang]

enphase

advantages of micro inverter:

~eliminates the need for a central inverter.
~allows you to miss and match modules.
~eliminates any shading issues. just cause one modules is shaded the whole string will not get affected.
~if the service panel is far from the solar panel then the enphase will eliminate the voltage drop that would occur from sending DC electricity from a long distance. AC can travel much further without voltage drop.
~enphase created a management solution called the envoy, it allows you to track module preformance.


disadvantages:

~expensive
~new on the market and still needs to be proven on the market.
~inverter will be exposed to outside temperatures

[Mike90250]

eliminate the voltage drop that would occur from sending DC electricity from a long distance. AC can travel much further without voltage drop.

~enphase created a management solution called the envoy, it allows you to track module preformance.

AC or DC, it's not the type of power, it's the VOLTAGE.
A PV loop with 500VDC will have less loss than a 120VAC loop.

High voltage DC transmission lines are in wide use, with actually less loss than for an AC line (even after rectification and inversion, the capacitive losses at high voltages add up)

And that Envoy solution will cost you after the first year, it does not report to you, it reports to enphase, and you read your data from them. Neat revenue stream!

[philpaine]

And that Envoy solution will cost you after the first year, it does not report to you, it reports to enphase, and you read your data from them. Neat revenue stream!

Didn't quite understand that. How does that work? Can you elaborate?

Thanks

Phil

[Mike90250]

Didn't quite understand that. How does that work? Can you elaborate?

Thanks

Phil

You have to dig in the enphase manuals and see their website for monitoring

[ChrisPSolar]

So if I'm not mistaken from my reading on the subject you could wire as little as one panel, 230W, one inverter and tie it to the grid. As far as impact this wouldn't be huge, but for folks looking to start small, pardon the pun, this is big. This means you can spend around $1000 and generate power that can be fed to the grid. The minimum used to be about $6000-8000 becuase grid tied inverters were so expensive. Or am I missing something?

[Mike90250]

So if I'm not mistaken from my reading on the subject you could wire as little as one panel, 230W, one inverter and tie it to the grid. As far as impact this wouldn't be huge, but for folks looking to start small, pardon the pun, this is big. This means you can spend around $1000 and generate power that can be fed to the grid. The minimum used to be about $6000-8000 becuase grid tied inverters were so expensive. Or am I missing something?

Nope, that's about the idea. And when you plug each panel into the grid, thats AFTER the city inspection, and after the power producer agreement with the electric company. Gets boring after 3 or 4 times.

[solar_geoff]

Greetings:

What is the opinion of the Enphase Micro-Inverter? What I understand is it is a inverter per module, connects AC outputs per module therefore eliminating the need for high voltage DC. Typically such distributed components increase costs. The ad says it provide greater efficiencies. What are the trade offs? Is this just hype?

We have started to install these inverters on a limited basis, and there are certain advantages (i.e. smaller systems possible, shaded roofs, etc.) but there is a pretty good premium on the price vs. a traditional central inverter. Typically it has been running in the neighborhood of $.50 to $1 additional per watt. There are certain applications where they are well suited, but I still think that a properly designed central inverter system is the way to go most of the time. The enphase inverters are also not compatible with all modules due to thier DC voltage window so it is important to carfully check your equipment combination before buying. My $.02.

[philpaine]

Nope, that's about the idea. And when you plug each panel into the grid, thats AFTER the city inspection, and after the power producer agreement with the electric company. Gets boring after 3 or 4 times.

Yes - bureaucracy and solar energy seem to go hand in hand!

Is it not possible to short circuit (pardon the pun) the process after installing and connecting the 1st panel?

Ignoring the paperwork etc, it sounds like a great alternative - shame about the additional cost. Can we expect the cost of micro-inverters to come down in the near future?

Phil

[newenergy]

I would only use them on a very small system. I have to warranty a system for 10 years and inverters are the most likely thing to fail. I don't know how much Enphase will pay me to do a replacement, but I'd be worried that it wouldn't be enough to replace some inverter in the middle of an array. I'd definitely charge more for the extra risk as well as the extra purchase price.