What can we really expect with solar?

[native pepper]

The 435w from 460w was the best, on average it would be closer to 380w - 400w peak most sunny days on the bus. In winter at home, it's not unusual to be getting 4kw and over for most of the day from 4.5kw of panels. In Summer more like 3.5k+w, but the longer days 16 hrs of sun makes a difference. The panels are orientated to the winter solstice day, when the sun is low and we are lucky to get 7 hours of sunlight.

The 460w on the bus in winter in Tas used to struggled to get enough into the gel, lifepo4 made a difference and when we got the bulk charger, heaps of difference. When it's 1000w, should handle it well.

This morning when checking the portable pack being charged, it was only getting 135w from a 250w panel. Put this down to the orientation of the panel, in winter it regularly produces between 195w and 210w. On the boat there is 200w and it regularly produces 180-190w, which can be put down to reflection off the water and the normal cooling breezes, which help.

[Wilbor]

1050 watts solar
109v & 833 watts coming off the MH roof
62.3amps
Fly turd under 80%

Best I have seen is 64 amps but I didn't look at the watts

Midnight classic mppt controller

[T1 Terry]

1050 watts solar
109v & 833 watts coming off the MH roof
62.3amps
Fly turd under 80%

Best I have seen is 64 amps but I didn't look at the watts

Midnight classic mppt controller

The battery voltage when the 64 amps were coming in would be very interesting. Midnight Classic would be one of the top performing MPPT controllers, up there with Outback Solar and as they both started from the same base it's to be expected. I think the Midnight MPPT has a higher series string solar input voltage and few features like snow melting back feed into the panel string when required. Interesting that the output from the solar itself is only 80%, I would have thought this would be where the figures were the highest, before the controller used up some of that harvested energy to power itself.

T1 Terry

[Wilbor]

1050 watts solar
109v & 833 watts coming off the MH roof
62.3amps
Fly turd under 80%

Best I have seen is 64 amps but I didn't look at the watts

Midnight classic mppt controller

The battery voltage when the 64 amps were coming in would be very interesting. Midnight Classic would be one of the top performing MPPT controllers, up there with Outback Solar and as they both started from the same base it's to be expected. I think the Midnight MPPT has a higher series string solar input voltage and few features like snow melting back feed into the panel string when required. Interesting that the output from the solar itself is only 80%, I would have thought this would be where the figures were the highest, before the controller used up some of that harvested energy to power itself.

T1 Terry

Battery was 13.3v with the 62.3amps. I was making it work with a 75amp load on the inverter. Roof panels are not flat due to the shape of the roof. The two centre ones are flat and the two left hand side ones are on an angle facing out and the three right hand side ones facing out the other way so I don't get the best sun angle at all but I do get enough

[T1 Terry]

1050 watts solar
109v & 833 watts coming off the MH roof
62.3amps
Fly turd under 80%

Best I have seen is 64 amps but I didn't look at the watts

Midnight classic mppt controller

The battery voltage when the 64 amps were coming in would be very interesting. Midnight Classic would be one of the top performing MPPT controllers, up there with Outback Solar and as they both started from the same base it's to be expected. I think the Midnight MPPT has a higher series string solar input voltage and few features like snow melting back feed into the panel string when required. Interesting that the output from the solar itself is only 80%, I would have thought this would be where the figures were the highest, before the controller used up some of that harvested energy to power itself.

T1 Terry

Battery was 13.3v with the 62.3amps. I was making it work with a 75amp load on the inverter. Roof panels are not flat due to the shape of the roof. The two centre ones are flat and the two left hand side ones are on an angle facing out and the three right hand side ones facing out the other way so I don't get the best sun angle at all but I do get enough

109v and 833w so that must have been on the input side, so 7.65 amps coming in? 833w coming in and 828w coming out, can't complain about that and I wouldn't mind betting there are few that can match that sort of efficiency through their MPPT controller. Over all efficiency is 78.9% and as you say, not all the panels face the sun at the best angle at the same time, so quite a good output that would hold for a lot longer through the day.

T1 Terry

[Wilbor]

Yeah T1, I am happy with the output and it's been working very well down here in Tassie with the cool to cold weather and long days. I have been getting 20 amps at 0730hrs and still getting 10 amps 12 hours later

[bagmaker]

so on the data here, Native Pepper, Peter & Sandra (and T1 to a lesser extent) are getting a 15% better result than the rest of us, stuck around a surprisingly even 80%. A few points here or there could be said about wire sizing, panel type and angle, sun intensity, heat, etc. But 94% is way off the curve.
How come? Guys can you share some insights? Any lurkers care to add their figures?

[bagmaker]

Might be a while before it hits main stream, but check this out http://www.altadevices.com/technology/ 31% efficiency as far as I understand it means 310watts from every sq mtr of solar cells. This means the roof area of an 11mtr motorhome could harvest 34kWh of electricity each full sun day by using the 5 hrs peak sun per day formula, that is around twice the power used by the average home per day in Australia.
Considering the first commercial cells were 2% efficient back in 1955 at a cost of US$1785/watt we have come a long way at around $1/watt being seen quite often these days. Where will the sq mtr efficiency/$$ per watt be in another 5 yrs? I wonder what the required efficiency would be to actually generate useable energy during a full moon?

T1 Terry

my dodgy maths reckons their advertised 260w/sq.m is a bit less than that
still beats the current 160-odd watts / sq.m though. A decent bus roof could pull 5 kw......

[Peter and Sandra]

Bagmakers last comment re full moon is funny, we've had a very small charge on moonlit nights and even when parked in a shed with clear panels in the roof.

[Dot]

Full moon and solar??? Oh boy we are sitting on a goldmine so they say