StandAlone. Plenty of inconsistencies :(

[tecnun]

Dear team,

I am sorry to say that your stand alone simulations are very poor. At "the time of truth" (i m involved in a energization of an island) PVsyst is completely failing:

1) Hourly results are inconsistent. Whereas report says e.g that my system covers 45% (55% generator) when i make excel tables with hourly results it seems that hourly energy load is equal to energy for the user --> hour by hour along the whole year my system covers 100%

2) When I set a generator, magicly the smaller i choose it the better my system fullfils the loads along the year.

3) Sometimes when i add more batteries the results are better, or said in other words, sometimes i reduce for ex. a subsystem of 168 batteries (48 V system with 24 x 7) to only 3 parallels, and the result is almost the same...should we save now battery investment or again there is an inconsistency??

The fact is that i un capable to design the microgrid of this island, there are lots of money and prestige in this "game" and definitely I cannot rely on PVsyst.

CAN YOU TEAM SOLVE SOMETHING OF THIS? Please Andre i wish you could work it out...maybe in new releases.

BR José (Tecnun)

[tecnun]

A correction in my explanation:

"Sometimes when i add more batteries the results are WORSE"

Best Regards J

[André Mermoud]

I don't understand well what you mean. We should take the questions one after the other with more details.

1. - E_Load is the energy needs, E_User is the energy really provided to the user. If you have a back-up generator, it is quite normal that these values are equal. A part comes from the PV, and another part from the Genset. The PV yield is named "E_Avail" (available solar energy).

2. - If you have a back-up generator, if it is sufficient it will fulfill the user's needs in any case. I don't see how your load is not fulfilled with big generators. Please give more information.

3. - The battery size stores the produced energy, but doesn't produce any energy more... If you over-size the battery pack (over, say 5-8 days of autonomy, depending on your climate) you don't have any additional yield: the results will indeed be about the same. Now if the batteries are highly oversized, they may have losses which compensate the storage benefit.

In the present time I don't see any dys-functioning in the topics you are mentioning.

[tecnun]

Thanks André,

There are a lot believe me, not quite severe but in my opinion not proper for the best PV software of the Market, being fair there are also "tricks" for overcoming them but you have to work them out.

For instance, i ll say one: The smaller the genset is, the better coverage you obtain, i mean in terms of solar fraction (direct or stored). Please try with examples. Of course I finally got rid of any generator and in the final tree I suppose all is left can be supplied by the generator, then I go to the hourly analysis and the rest is a good use of excel management, iterations and patience.

If you let me go farther with these inconsistencies I can explain some more, specially in the hourly files (offgrid and ongrid)

Best Regards

Jose

[tecnun]

My apologies to the first error I said in my first message, I thought E user was renewable not complete with genset, I found it redundant frankly.

BR

J

[voarn2]

Dear team,

I am sorry to say that your stand-alone simulations are very poor. At "the time of truth" (i m involved in the energization of an island), PVsyst is completely failing:

1) Hourly results are inconsistent. Whereas the report says, e.g. that my system covers 45% (55% generator) when I make excel tables with hourly results, it seems that hourly energy load is equal to energy for the user --> hour by the hour along the whole year my system covers 100%

2) When I set a generator, magically, the smaller I choose it, the better my system fulfills the loads along the year.

3) Sometimes, when I add more batteries, the results are better, or said in other words, sometimes I reduce, for ex. a subsystem of 168 batteries (48 V system with 24 x 7) to only three parallels. The result is almost the same...should we save battery investment now or again there is an inconsistency??

The fact is that I un capable of designing the microgrid of this island. There are lots of money and prestige in this "game," and I cannot rely on PVsyst.

CAN YOUR TEAM SOLVE SOMETHING OF THIS? Please, Andre, I wish you could work it out...maybe in new releases. Escape Promo Code

BR José (Tecnun)

can any explain some more, especially in the hourly file