Hi.
We are being quoted at the moment for a 4kW PV install, with 16 x Sanyo HIT250 panels. Roof is approx 45 degrees and south facing. Location is North Hampshire. Partial shading of some of the panels in the morning and some others in the afternoon.
The installer is recommending a SB 3800V inverter with 2 strings of 8 panels. Both obviously going to the single MPPT. S
unny Design seems to indicate (as far as I can tell) that a SB 4000TL with 1 string going to each of the MPPTs would give a greater output. I would also expect this would better handle the partial shading issues. The installer is willing to fit this if I insist, but believes that it will be less efficient. I believe that the startup voltage is lower on the 4000TL, so this would mean that it would be generating quicker at the start of the day?
A possible issue with the 4000TL is that the DNO might have objections as it could theoretically produce more than 16A. Does anybody know if Scottish and Southern are likely to be friendly or not regarding this?
If we do have to restrict the 400TL to 3.68kW, I am not sure what effect this would have on the predicted production figures as I have not been able to model this in Sunny Design.
I welcome opinions on which inverter I should specify.
We are being quoted at the moment for a 4kW PV install, with 16 x Sanyo HIT250 panels. Roof is approx 45 degrees and south facing. Location is North Hampshire. Partial shading of some of the panels in the morning and some others in the afternoon.
The installer is recommending a SB 3800V inverter with 2 strings of 8 panels. Both obviously going to the single MPPT. S
unny Design seems to indicate (as far as I can tell) that a SB 4000TL with 1 string going to each of the MPPTs would give a greater output. I would also expect this would better handle the partial shading issues. The installer is willing to fit this if I insist, but believes that it will be less efficient. I believe that the startup voltage is lower on the 4000TL, so this would mean that it would be generating quicker at the start of the day?
A possible issue with the 4000TL is that the DNO might have objections as it could theoretically produce more than 16A. Does anybody know if Scottish and Southern are likely to be friendly or not regarding this?
If we do have to restrict the 400TL to 3.68kW, I am not sure what effect this would have on the predicted production figures as I have not been able to model this in Sunny Design.
I welcome opinions on which inverter I should specify.
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