Pitch and orientation

[Jordn]

Hi everyone & Valentin,

we're creating an orientation and pitch chart to show others clearly the kind of performances to expect. Like a compass - difference in Orientation axis follows around the chart, and difference in pitch runs from the centre to the circumference in smaller to larger circles (0 degrees to 80 degrees pitch). So the first circle from the centre represents 10 degrees pitch, the second circle from the centre represents 20 degrees pitch and so on. It's quite smart and will hopefully give clarity to others than Northern facing systems still produce an acceptable level of generation. This is what we've made so far as an example;

 

...All we've done above is estimated what we think the chart would look like.

We'd like to make a PV Sol experiment on what the chart would actually look like. So to do this I'm noting down the PV Sol PV Generator Energy (AC Grid) value for every different combination of orientation and pitch. I've made one for Newquay UK using 14 SunPower Maxeon2 350 panels and a solis 3.68kw inverter (no shading). Just as an illustration;

 

Just using my simple head I would have initially thought East and West orientations would mirror eachother down the South line, as in East and West would give equal or similar energy - lets say 20° due West would provide the same amount of energy as 20° due East.

But then this is Newquay, there's the ocean to the West which would skew the results to favour the West though a big water body Albedo.

 

So then I tried other locations; Baldhu UK, Norfolk UK, Riyadh SA and PV Sol shows West orientations generate more PV Generator Energy (AC Grid) than East orientations.

Couple of questions please;

• is there a location in the world where East and West orientations match PV Generator Energy (AC Grid)?
•  am I missing something here... generally speaking is it normal for West orientations to generate more than East?

 

Thank you everyone!!
 

Yours,

 

Jordan

 

[developer_mh]

Hi Jordn,

this is a very interesting project you are working on there! Thank you for sharing this.

In general, the climate data used to simulate the PV system have the strongest influence on the symmetry of the results. Other influences can come from the models used to calculate the irradiance on the tilted plane and so forth, the synchronity of the sun's coordinates with the climate data and the like.

I just checked this for some locations and climate data sources, and compared the orientations 90° (East) and 270° (West) with 180° (South), all at 30° inclination.

• Berlin with data from DWD: East brings 82,4 %, West 80,6 %
• Berlin with TMY data, also DWD, but different source: East brings 82,7 %, West 77,7 %
• Severn England, SAP 2012 dataset: East brings 82,6 %, West 81,9 %
• Newquay UK, interpolated in PV*SOL with Meteonorm 7.2: East brings 82,6 %, West 81,4 %

So, in contrast to your results, we have a higher irradiation on the East facing systems. This seems strange to me, could you provide a project file, perhaps? You can also send it via private message. Which version of PV*SOL are you using?

Kind regards,

Martin

[Jordn]

Hi Martin,

Thank you for your response!! Aye I've attached the file I've been using. Using version 2020.5.130. I'll take a look at the Severn England climate data. Thanks again!

Yours,

Jordan

PV Sol Orientation and Pitch.pvprj

[Jordn]

I checked out the Severn England SAP 2012 dataset and these are the results;

14 x SunPower Maxeon2 350 + Solis 3.68kW (no external shading)

 

		Orientation from South (Clockwise)
		90	105	120	135	150	165	180	195	210	225	240	255	270
Pitch	60	3861	3489	3105	2742	2423	2175	2070	2116	2317	2599	2919	3260	3599	60	Pitch
	50	4090	3732	3357	2999	2691	2497	2417	2443	2593	2862	3176	3508	3836	50
	40	4286	3961	3622	3301	3053	2902	2833	2849	2955	3165	3488	3748	4047	40
	30	4445	4176	3903	3648	3455	3334	3278	3287	3363	3516	3737	3984	4236	30
	20	4568	4376	4186	4013	3870	3777	3734	3739	3794	3899	4047	4219	4401	20
	10	4640	4541	4446	4359	4288	4237	4210	4211	4239	4290	4361	4448	4544	10
	0	4640	4640	4640	4640	4640	4640	4640	4640	4640	4640	4640	4640	4640	0
	10	4640	4735	4819	4887	4935	4959	4957	4932	4884	4817	4734	4641	4544	10
	20	4568	4747	4906	5034	5123	5167	5166	5120	5033	4909	4756	4584	4401	20
	30	4445	4694	4913	5091	5213	5272	5272	5211	5093	4924	4718	4483	4236	30
	40	4286	4585	4847	5060	5207	5279	5277	5206	5067	4865	4618	4341	4047	40
	50	4090	4420	4712	4946	5106	5191	5186	5101	4954	4733	4458	4156	3836	50
	60	3861	4208	4505	4751	4921	4999	4996	4916	4754	4526	4245	3926	3599	60
		90	75	60	45	30	15	0	345	330	315	300	285	270
		Orientation from South (Clockwise)

 

And then turned them into %'s using the largest value as 100%.

 

		Orientation from South Clockwise
		90	105	120	135	150	165	180	195	210	225	240	255	270
Pitch	60	73	66	59	52	46	41	39	40	44	49	55	62	68	60	Pitch
	50	77	71	64	57	51	47	46	46	49	54	60	66	73	50
	40	81	75	69	63	58	55	54	54	56	60	66	71	77	40
	30	84	79	74	69	65	63	62	62	64	67	71	75	80	30
	20	87	83	79	76	73	72	71	71	72	74	77	80	83	20
	10	88	86	84	83	81	80	80	80	80	81	83	84	86	10
	0	88	88	88	88	88	88	88	88	88	88	88	88	88	0
	10	88	90	91	93	93	94	94	93	93	91	90	88	86	10
	20	87	90	93	95	97	98	98	97	95	93	90	87	83	20
	30	84	89	93	96	99	100	100	99	96	93	89	85	80	30
	40	81	87	92	96	99	100	100	99	96	92	87	82	77	40
	50	77	84	89	94	97	98	98	97	94	90	84	79	73	50
	60	73	80	85	90	93	95	95	93	90	86	80	74	68	60
		90	75	60	45	30	15	0	345	330	315	300	285	270
		Orientation from South Clockwise

 

And then rounding each value into a range;

 

		Orientation from South Clockwise
		90	105	120	135	150	165	180	195	210	225	240	255	270
Pitch	60	75	70	60	55	50	40	40	40	40	50	60	65	70	60	Pitch
	50	80	75	65	60	55	50	50	50	50	55	65	70	75	50
	40	85	80	70	65	60	60	55	55	60	65	70	75	80	40
	30	85	80	75	70	70	65	65	65	65	70	75	80	85	30
	20	90	85	80	80	75	75	75	75	75	75	80	85	85	20
	10	90	90	85	85	85	85	85	85	85	85	85	85	90	10
	0	90	90	90	90	90	90	90	90	90	90	90	90	90	0
	10	90	95	95	95	95	95	95	95	95	95	95	90	90	10
	20	90	95	95	95	95	100	100	95	95	95	95	90	85	20
	30	85	90	95	95	100	100	100	100	95	95	90	90	85	30
	40	85	90	95	95	100	100	100	100	95	95	90	85	80	40
	50	80	85	90	95	95	100	100	95	95	95	85	80	75	50
	60	75	85	90	95	95	95	95	95	95	90	85	75	70	60
		90	75	60	45	30	15	0	345	330	315	300	285	270
		Orientation from South Clockwise

 

And then quickly transferring (inc. handling the results to make symmetrical for illustration purposes) the results to the previous chart (using Microsoft paint);

 

Yes so it looks much better using the Severn dataset, thank you. (Unlike my inception of that chart ahha).

 

Quick question if anyone is up for it please; speaking to my colleagues we suggest Eastern orientations should generate more kWh than West generation because the panels experience less heat losses as they're cooler in the morning. What else would suggest a difference in generation between the East and West orientations? I'm guessing this is a solar designer elementary question. Thank you!