Subjective listening impressions of alternate power (solar, generator, battery)

[sdolezalek]

I went through this decision process about a decade ago -- so my data could well be out of date.  At the time I had the benefit of working directly with the CTO of SunPower so we carefully considered the variables and decided to go with larger inverters rather than on-panel microinverters because they produced a cleaner wave form.  Even though I also have a Tesla S, we decided not to do Powerwalls, leaving the solar system as grid connected.  I separately added a gas generator, but only sized to power the core of the house so that we had heat, ability to cook and refigerate food.  Most importantly though I ran completely separate circuits for a) the part of the house that used the generator (which uses a manual transfer switch), b) for just the audio room, and c) for the rest of the house.  I also ran a dedicate underground cable in conduit from the street.  I can tell no difference whatsoever between when the solar system is generating power or at night.  Compared to my previous house on the same street, I now get complete silence on the audio system at full volume compared to a varying degree of background hiss in our prior home depending on how loaded the neighborhood circuits were. 

[sdolezalek]

11 minutes ago, PeterSt said:

 

Yes, this is something to just "know". Solar panels which get hot (and they logically will) become way less efficient. So they actually should be cooled.

In winter they are the most efficient, but not much sun in winter times ...

Unless you live in areas where the temperature gets very hot (over 100 degrees Farenheit on a regular basis) the temerature effect is not that large.  See table below.  The temperature coefficient is the percentage decrease in energy production for each increase in degree Celsius over 25, or 77 degrees Fahrenheit. The reduction in output is minimal, so you will probably not notice your solar panels performing any worse.  For reference, the temperature coefficient from major solar panel manufacturers’ data sheets is below. 

Panel	Brand	Temp. Coefficient	Rated Max Output
X21-350-BLK	SunPower	-0.29%/°C	350W
HIT N330	Panasonic	-0.26%/°C	330W
CS6K-300	Canadian Solar	−0.39%/°C	300W
TSM-PEG5-285	Trina Solar	−0.41%/°C	285W
Q.PEAK-G5 310	Hanwha	−0.39%/°C	310W

[sdolezalek]

29 minutes ago, PeterSt said:

But ...

If 0.3% is per degree Celsius, then a delta of say 40 degrees, means well over 10%. Mind you, the 40 degrees would be from the heat/hotness the panel gets. Not the air temperature. So I'm afraid it can be even quite some more (like 60 or 70).

 

The rating can't be for air temperature (or ambient) because it would exclude the collecting of heat. Step in your car on a hot day and you know what I mean.

No the rating is for ambient temperature.  Yes, the panel gets quite a bit warmer than that, but in order for consumers to be able to use the rating they need it in the form of ambient temperature so they can compare for the temerature ranges of where they live.