Dollars per watt

[DavidVC]

I have a very simple question:

Does the "dollar per watt" cost that is always mentioned incorporate the efficiency of a panel or not? In other words: spending the same amount of money on 2 panels with the same dollar per watt price, will they produce the same amount of electricity?

That's the way I always thought it was but some people made me doubt... Also, since First Solar is producing at say 0.75 $/W and SunPower at 1.7 $/W...can anyone explain to me how come there's still competition? Because I don't think the space factor is that much of an issue, right..?

Thank you very much!

[s.xavier]

I have a very simple question:

Does the "dollar per watt" cost that is always mentioned incorporate the efficiency of a panel or not? In other words: spending the same amount of money on 2 panels with the same dollar per watt price, will they produce the same amount of electricity?

That's the way I always thought it was but some people made me doubt... Also, since First Solar is producing at say 0.75 $/W and SunPower at 1.7 $/W...can anyone explain to me how come there's still competition? Because I don't think the space factor is that much of an issue, right..?

Thank you very much!

I'm not sure what your question pertains to but to begin with First Solar and SunPower use two completely different technology so they will have fundamentally different cost structure. Production costs will vary so try to use it as a benchmark because the only way to calculate real costs is if you were part of their management team... You have to realize that a lot of the numbers out there are published with a marketing spin to it. In other words, you will have to do your own research and come to your own conclusion on the matter.

The debate between thin film and crystalline modules will continue indefinitely but imo competition is a good thing because it will force companies to continue to innovate. SunPower makes pretty neat modules likewise FirstSolar. When you refer to space are you talking about usable area? Depends on your installation site and yes it matters. Take a look at this article on thin film solar panel vs crystalline solar panel

Continue to read up on it and you will find out the difference between them and come to your own conclusion. As for myself, the higher costs using First Solar doesn't work for me. They are indeed more efficient (depends on your criteria) but they are just a touch too pricey imo...

[DavidVC]

Thanks for your reply! Even though I was more expecting a really simple yes or no answer

I have been studying all the different PV technologies full-time for a month now so I think I got the basics covered. When doing my company presentation today though, everyone was expecting c-Si to be more expensive per square meter but making up for it by providing higher efficiency and thus having a lower cost per watt. Instead, even on cost per watt the less efficient thin film technologies prevail by far, so they were asking if perhaps the efficiency was not yet incorporated in the cost per watt...

[Naptown]

I would stay away from the thin film the stuff generally does not hold up well or for long. Use hard crystal only if you want it to last.
Now to answer your question. A 200 watt module is a 200 watt module and a Sunpower 200 watt will produce the same amount of electricity as any other 200 watt module. There are 2 differences though. the Sunpower will be physically smaller due to the high efficiency and carries a premium price tag to go along with it. If space is not a problem then I would not suggest using Sunpower or any of the high efficiency modules as you are wasting your money.

[DavidVC]

I would stay away from the thin film the stuff generally does not hold up well or for long. Use hard crystal only if you want it to last.
Now to answer your question. A 200 watt module is a 200 watt module and a Sunpower 200 watt will produce the same amount of electricity as any other 200 watt module. There are 2 differences though. the Sunpower will be physically smaller due to the high efficiency and carries a premium price tag to go along with it. If space is not a problem then I would not suggest using Sunpower or any of the high efficiency modules as you are wasting your money.

So it's the expected "yes" answer, thank you!

It's basicly what I thought all along but I just got confused by my bosses hehe.. So theoretically, assume a panel A with 20% efficiency costing 2 dollars per watt and a panel B with 10% efficiency costing 1 dollars per watt. Covering my roof with panel A would cost 4x more than covering it with panel B? Neglecting system cost of course...

[s.xavier]

So it's the expected "yes" answer, thank you!

It's basicly what I thought all along but I just got confused by my bosses hehe.. So theoretically, assume a panel A with 20% efficiency costing 2 dollars per watt and a panel B with 10% efficiency costing 1 dollars per watt. Covering my roof with panel A would cost 4x more than covering it with panel B? Neglecting system cost of course...

Lets say this... For example, you have the following:
1) 240w First Solar thin film - $540
2) 240w SunPower - $540

The challenge is that for the First Solar module you will need 3x of the F3 series meaning the footprint will be larger. Even at a lower cost, does it make much sense if you need 3x as much to achieve a certain output? If the First Solar module had an identical footprint as the SunPower module then you can say yes it makes more sense using the thin film (just one criteria though).

Personally imo i think the best question to ask is if you were to have a limited space what would make the most financial sense for maximum energy output.