SolarSystemDesigner.com - website for designing and visualizing pv systems

[solarsystemdesigner]

Hello - new to the forum. I started building a pv system, and after making some mistakes, I put on my programmer hat and made a website that I hope would help others to avoid the same. On solarsystemdesigner you can set your system size, voltage, panel type and battery type. It will dynamically create a system of arbitrary size showing all of the electrical connections. Because I'm relatively new to this, I would appreciate feedback on the site, especially if there's anything I got wrong. If you have a chance, take a look at solarsystemdesigner.com - any feedback would be appreciated! Oh of course it's completely free.

 

[sunshine_eggo]

To be frank, you haven't achieved even a minimal level of function. Whatever mistakes you may have made, your website output would allow a great number of mistakes.

Why only 4 panels size choices?
Why assume a panel has specific voltage and watts AND have them be wrong (you can't apply your "75%" to your output)?
Why only put two panels in series with 15 strings in parallel?
Where are the fuses/breakers/PV disconnects?
Why would you show an inverter connected to the load port of a charge controller. This is NEVER done.
Why insist on using 12V batteries?

IMHO, the output is completely useless and is likely to lead a beginner horribly astray forcing them to make multiple rookie mistakes.

Good luck.

 

[robbob2112]

Why limit the 48v batteries to 200ah, 304ah cells are easily availble and it would be easy for someone to do 16s2p or more. Some folks go completly nuts. Better to ask if the have ready made or diy then if diy allow entry in the format of #s#p and allow entry of cell size verse a drop down or you will forever be updating it.

For panels asks how many or calculate it from other bits. For mppt ask a brand and have specs on the popular ones. Then calculate optimal setup... and sub-optimal and let uses choose.

Batteries - select a voltage based on inverter size... 12v only makes sense for small van sized systems and not even then most of the time. Over 5kw the only voltage that makes sense is 48v. I chose 9 parallel 48x200ah and what it spits out is nothing like anyone uses.



Where are the busbars? How about calculating size for it from information?

Nomial system voltage?

Fusing, fusing, fusing. Combiner box? Breakers, SPD, lightning arrestors?

Account for ac coupled or dc coupled. On-grid or off-grid. Include grounding wires.

Line taps?

You really need to have a couple of basic designs to choose from that populate a basic blank canvas, the have equipment on the side to drag/drop..... like drawio, visio, or any of the others... more limited since only for solar.



I think you need to spend a month or 3 reading on here then start designing a website once you have an idea what is correct and what isnt.

Also some parts or the world use 3 phase power as the regular voltage. Account for it. 240 spli-phase like the us uses typically requires 2 or more inverters stacked in pairs, depending on the inverter

 

[solarsystemdesigner]

Obviously I came to the right place. Thanks so much for the responses. This is exactly the feedback I needed. I'm trying to make something actually useful and I clearly have a ways to go in my understanding of these systems. I will be following your advice for sure, reading up on these forums and I hope to make a visualization that more accurately reflects the realistic options in pv systems.

 

[sunshine_eggo]

You need to allow far more detailed inputs to illustrate to new users that there is NEEDED detail and complexity.

 

[Supervstech]

Search the site to find average schematics, formulas for low temp VOC correction, change the drop down to be an entry, you can adjust to include battery voltage, controller voltage limits amperage limits, fuse locations, etc.

Read a LOT of responses on those searched threads, and incorporate into your site.

You could turn this into a valuable tool, but right now it is dangerous and very short sighted...

 

[A.Fenderson]

I'm pretty new to all this as well. I like the idea, and the relative simplicity of the output and diagrams. I think to achieve baseline utility, you'll need to focus on these minimum criteria:
* allow user to specify the exact specs of their panels (all the numbers that appear on the label on the panel itself), and use those numbers in the calculations
* allow user to specify these specs of their charge controller:

* minimum PV input voltage​

* maximum PV input voltage​

* controller optimal operating voltage (not always specified by manufacturer, so allow skipping it as input and calculate it as something akin to Vmin + 0.75*(Vmax-Vmin) (note: this is a guess--someone correct me if this is a bad means of guesstimating it)​

* maximum PV input current/wattage (some devices specify one rather than the other/both, or occasionally neither)​

* allow user input of either a targeted kW production target for the array and then calculate how many panels they'll need and in what config, or allow them to specify the number of panels, and then calculate the production capacity and the likely-best array config.

I think once you have baseline utility, along with a disclaimer that you are not showing/calculating necessary safety devices, you can start incorporating some of the other features that would make it a far more useful and flexible tool.

Page layout considerations:
* for panels in series or batteries in parallel, don't stack them vertically with a width of one: alter the wiring to allow the array/bank to flow horizontally, left-to-right, to the page width, then wrap to a new line (since you're presumably targeting desktop on a website and not mobile via an app).
* as mentioned, show the inverter DC input attached to the battery bus bar, not the charge controller load output (which to my understanding may not even exist on many modern charge controllers). Along with this, instead of allowing the user to check "Batteries" at the top, maybe have them choose either "off-grid" or "grid-tied". The former pretty much assumes batteries, the latter pretty much assumes no batteries--again, this is for baseline utility of covering the most common scenarios, though, and not always true.

 

[robbob2112]

Oh yeah,

Calculate current going through every wire. Every wire should be sized 120% of expected current and fused 125% of expected current. This will prevent nuisance blows.

Read this thread and see if you can incorporate optimal position on busbars for uplink cable positions.

Calculation of parallel string battery currents

Hi, everybody! I'm a retired EE. I didn't want my EE skills to fade away after retirment, so I exercise them when I can. Whenever I see a non-trivial circuit analysis problem on one of various forums I frequent, I challenge myself to solve it. Recently I watched Will's video about current...

diysolarforum.com

Checkbox for overpaneling and then offer up safe options

 

[45North]

Could AI do this?
Has anybody tried?
As someone already mentioned AC electrical standards vary around the globe. Suggest you start with one (North America?) and start there.

 

[Supervstech]

Obviously I came to the right place. Thanks so much for the responses. This is exactly the feedback I needed. I'm trying to make something actually useful and I clearly have a ways to go in my understanding of these systems. I will be following your advice for sure, reading up on these forums and I hope to make a visualization that more accurately reflects the realistic options in pv systems.

I recommend you actually build a solar system so you see how items actually connect and what needs to be used.

I dont know anyone that connects inverters to solar controllers.

Solar controllers operate the battery charging. The load is for controlling some battery voltage device, like a light or a switch.
Inverters connect to the battery, as they draw far more amps than most charge controllers have.

 

[robbob2112]

First thing you need to do is put a large red label on the top of the website saying it is not for actual use and it is experimental and under development

 

[Skypower]

The OP is well meaning, but dear lord the variables are so numerous that it boggles the mind. Take panel sizing criteria. Cold weather voltage increase must be considered based on anticipated coldest local temperature. Then there’s “overpaneling”, something that I won’t consider with my third tier inverter because I’ve seen well above rated solar panel output due to “cloud edge effect” at least a dozen times a year. Thankfully I’m in a warmer climate so I don’t have the cold weather OCV issue so I can run closer to the voltage limit of the MPP ,however I’m well below the wattage limit of the system to allow for the occasional power jump so my cheaper system doesn’t go poof.
The OP should;
Have a disclaimer, “in development” because there will be mistakes and omissions. More blanks for more data points. Links to things that he hasn’t had a chance to incorporate data into the project. Add explanations, for example. Why it’s best for a 48 volt system to use 48 volt batteries, not four 12 volt batteries in series.
NOT GIVE UP!
The more information out there the better!

 

[solarsystemdesigner]

Thanks so much for the feedback. I have updated the site to include a disclaimer and removed the erroneous connection from the charge controller to the inverter. I will be doing more research and updating the site with more of your suggestions.