Solar Panel / Inverter Recommendation For Hot Garage Roof.

[Vegelen]

Can anyone recommend any solar panels with high efficiency and low temperature

coefficient, similar in size to Sanyo 240 HITS?

I'd prefer the solar panel to be mono crystalline, efficient, reasonably priced, with a

decent warranty / product quality.

9 solar panels need to fit onto a hot summer garage roof in a 3x3 landscape array.

Solar panel width can be between 750mm and 875mm.

Solar panel length can be between 1450mm and 1715mm.

Garage roof is 2.68m x 5.20m.

Solar panels may be paired with a system that accommodates variable

shading at different times of the day.

Am considering using Solar Edge Inverters with power maximisers, Enecsys micro

inverters or Fronius IG inverters with decent solar panels.

 

[Somecamel]

Why not just use the Sanyo's?

 

[Vegelen]

Sanyo's are good in bright light but aren't very good in low light conditions.

They are too expensive for what they are.

Better solar pv alternatives exist with better price, performance metrics.

I am familiar with lots of good inexpensive panels, but many are typically 1650 x 992 in size.

I am trying to find an inexpensive,smaller, monocrystaline panel with an efficiency in

the range of 15.5 - 18%.

Suntech have recently released pluto technology solar pv panels like "Suntech

Hiperforma Pluto Ade - 200".

They have an efficiency of 15.7%, a temperature coefficient of -0,38%/K and

excellent weak light performance resulting in a 2% - 5% better energy output than

earlier Suntech panels without Pluto technology.

I wondered if anyone knew of a better alternative.

 

[Vegelen]

JA Solar JAM5(L)-72-215/SI
Power	215.0
Maker	JA Solar
Model	JAM5(L)-72-215/SI
Size	1580mm x 808mm (11362cm[SUP]2[/SUP])
V[SUB]mpp[/SUB]	38.16V
V[SUB]oc[/SUB]	46.1
I[SUB]mpp[/SUB]	5.63
I[SUB]sc[/SUB]	5.79
α	0.0004
β	-0.003
K	-0.0044
Efficiency	16.84%

- Ranked 6th Most efficient mono crystalline panel in Mid 2011.

 

[Vegelen]

Trina Solar TSM-210DC80.08 Power 210.0 Maker Trina Solar Model TSM-210DC80.08 Size 1581mm x 809mm (11383cm[SUP]2[/SUP]) V[SUB]mpp[/SUB] 38.8V V[SUB]oc[/SUB] 46.6 I[SUB]mpp[/SUB] 5.42 I[SUB]sc[/SUB] 5.78 α 0.0005 β -0.0035 K -0.0045 Efficiency 16.4%

- Ranked 7th Most Efficient Mono Crystalline Panel in 2011.

 

[Del Boy]

Was just doing a quick bit of maths, and I think if you are using SolarEdge (which I think would be best with the shading issues) then using Sanyo 240s would cost an extra 25% on the total install price. For that you'll get 20% more peak power on the roof, and you will have 50% less losses from the heat off your hot roof.

I think Sanyo/Panasonic also advertise HIT as being good in low light. My understanding is that HIT is a hybrid containing thin film, and thin film outperforms mono in low light... and outperforms mono at high temps.

Just my thoughts, but you are right, they are expensive! But for smaller roofs with expensive inverters I think the outlay will probably pay itself off.

 

[SolarCity]

Vegelen, you do understand that being ranked by efficiency is a bit misleading?

It simply means that you get more watts per square metre. Utterly irrelevant on roofs where space isn't limited.

 

[Earthstore]

How come this roof is hot?

 

[Vegelen]

Roof space is limited, as stated: 5.20m x 2.68m.

Efficiency of solar panels is relevant in confined spaces.

 

[Vegelen]

Using Sanyo 240s would cost an extra 25% on the total install price. For that you'll get 20% more peak power on the roof, and you will have 50% less losses from the heat off your hot roof.

Sanyo 240 HITS wont give 20% more peak power over many excellent, efficient,

cheaper, solar panels out there sited in North West England.

It is closer to 8-12% (dependant on the weather).

I've seen many good quality, inexpensive, efficient solar panels outperform Sanyo's

HITS in real world conditions, with decent inverters.

Certain JA Solar panels, paired with Fronius inverters comes to mind.

The very low temperature coefficient of -0.3 of Sanyo 240 HITS will improve

generation when the weather gets warm and the roof hot versus alternative panels,

but it wont give any appreciable gain in generation over some

newer alternative panels which are inexpensive with fairly low

temperature coefficients approaching -0.38 (from the typical -0.45).

Sanyo /Panasonic Hybrid HITS claim to be good in low light and high light due to

their hybrid status, but do they outperform many far cheaper panels in low light

conditions like the Suntech STP250S-20 Wd Plus?

Not in my experience, having seen lots of data showing otherwise.

They tend to outperform in hot weather with bright sunlight, but

they also loose ground over many cheaper panels in lower light conditions and bad

weather which we seem to have a lot of in Blighty.

I like Sanyo 240 HITS but wish that Panasonic would make them cheaper, to

increase their take up in the market, before its too late and better technology

arrives to surpass it.