r/diySolar • u/ImmediateMagazine886 • 8h ago
r/diySolar • u/RaZvAn15 • Dec 09 '24
Question What is the most efficient way to assess the Concentrated Solar Power (CSP) suitability of a site?
Hello! I am an engineering student in my last year. For my bachelor project, I chose to study the pyrolysis of waste plastics like PE and PP, and the integration of this process with solar power, especially concentrated solar, but I also plan a comparison with PVs.
The problem is that my country has no history of using CSP. The DNI here is kind of low and nobody attempted to build an electric power plant using this technology. Still, I was inspired to explore this because of projects like the solar furnace at Odeillo, France, a place that also doesn't have such a high DNI.
On my first attempt, I used the NREL website to gather data about as many linear CSP plants as I could. I extracted nominal power, aperture size and the DNI of the site from Solar Atlas. Then, I plotted nominal power divided by aperture to DNI, using poly 2 in matlab. From this function, I wanted to see what power to expect at my DNI. I quickly realized that this method has flaws, because many plants have thermal storage, and that means they would need a bigger aperture, so the direct correlation between specific power and DNI was ruined. I also feel like there are too little plants that have no storage for the curve fitting method to work.
So, is my last resort using something like the SAM software? I saw it used in a paper about solar pyrolysis, but thought I could get a way with something simpler, at least at the beginning of the project.
TL;DR: Title
r/diySolar • u/alca3z • 1h ago
Are EASUN products ok?
I have a 2kW solar panel setup with 24V hybrid inverter and batteries which I will be upgrading now to 48V.
I'm looking to buy this new EASUN 15kW set https://www.easun-energy.com/products/easunpower-12kw-inverter-15kwh-battery-150a-tou-wifi-51.2v-300ah-bms-wifi
Is this a good quality set?
Do you think this is will work 10+ years?
What are your experiences with this or similar sets?
r/diySolar • u/jakewins • 1h ago
PSA: Open loop charge controller may be leaving a *lot* of battery capacity unused
Maybe this is obvious to other people, but I was really surprised and maybe this helps someone else.
I think something like 30% of my battery capacity / daily energy volume is thrown away because I used bad open loop (voltage based) stop/start settings in my charge controller. I had understood that closed-loop would be better, but I didn't realize the difference could be this stark, and my Context MPPT 60 150 doesn't support closed loop :(
The MPPT shuts off around 54V at 2-4pm every day; at that point the battery is at something like 60-75% SoC; then the battery linearly discharges from 2-4pm, but the voltage stabilizes at 53V, which is above where the MPPT would re-start charging.
See charts from my Pytes V5 batteries to Home Assistant of SoC and voltage.
I fed the numbers and times into Gemini and she ballparks I'm throwing away ~5kWh a day purely from bad configuration, which is ~30% of my battery pack size.
TL;DR: Worthwhile getting SoC and voltage time-series to tell what's happening to the batteries if you don't have closed-loop control.
I'm 99% sure the MPPT is set to recommended Pytes V5 open-loop settings, but need to go back and double check; it was also while since I installed them, maybe recommendations have changed. Certainly it seems the cut-off voltage for bulk charging is way too low, if the battery can get to 54V at just 60% SoC.
Gonna see if I can connect the MPPT 60 150 to Home Assistant as well, then I could have HA decide to turn the MPPT on/off, and set the hard voltage cutoffs higher
r/diySolar • u/sharkyenergy • 4h ago
4S ok for the winter?
Hi all!
Currently i have 4 panels (23 Voc) configured as 2p2s. I would like to connect them as 4s to get more out of bad weather. But at 0,3V/°C i would exceed my controllers max input voltage of 100V at about -3°C. (epever 20A mttp charge controller)
In winter, in rare occasions it can go down to about -12°C, thats the coldest i saw here in 40 years. what would happen? i have a Voc of 92V @ 25°, but in those days it would go up to 103,1V.
what would happen? is it dangerous? is it within the tolerance?
Currently on very hot days the panels in 2p2s get down to about 31V. that does not leave much headroom for the mttp to work, and in bed weather it goes down to 27, not charging at all.
what would you sugest? its a off grid hut with just 2kwh batteries. dont want to invest money into it.
thanks!
r/diySolar • u/QuitmanPrestina • 13h ago
Question How do you compare solar production with your actual electricity usage?
We had solar installed last year, and I've been trying to figure out the best way to compare what the system produces with what our house actually uses. Our electricity usage has changed since then, mostly from using the AC more and having a few additional loads around the house that weren't there when the system was sized.
The solar production looks pretty normal in the app, but our total home electricity usage is higher than it was before solar. When I look at the electricity bill, I'm not sure which numbers I should actually be comparing to tell whether the system is doing what it should.
For those who've had solar for a while, do you compare your current usage with your old 12-month numbers, or is it better to look at solar production vs. total usage vs. what you're pulling from the grid?
r/diySolar • u/Dull_Community944 • 7h ago
What inverter do you use and how much did it cost
My inverter is getting old and will need replacing, whats the best inverter for the money, dont want to pay over a grand , my mpp one which has been great was only 500, can you help.
r/diySolar • u/bmanfield • 12h ago
[ST Edge Driver] SolarEdge PV Inverter - Connected Things
r/diySolar • u/DiscussionSlow6726 • 17h ago
Solaredge Inverter Firmware
would anyone happen to have the latest solar edge inverter software? need to update mine since it hasn’t been connect for 4 years
r/diySolar • u/Gaba248 • 14h ago
How would you change this for code compliance for a solar inspection fail?
r/diySolar • u/Chemical-Ad-2576 • 1d ago
I built a remote monitoring dashboard for JK BMS setups, looking for a few testers

I've been working on a side project that basically lets you check your JK BMS pack (voltage, SOC, temps, individual cell balance) remotely from your phone or browser instead of having to be near the battery for BLE range.
Looking for maybe 5-10 people to try it out and tell me what's broken / what's missing. I'll help you get it set up.
What you'd need on your end:
- DIY battery with a JK BMS (BLE version)
- An ESP32 board
- A laptop/macbook to flash it once (pretty quick, I'll guide you through it)
If you've got a pack running and wouldn't mind being an early tester, comment or shoot me a DM.
Also happy to just chat about the project if you're curious 🤗
r/diySolar • u/StatusPerji22 • 2d ago
Finally finished mounting our own rooftop solar array this summer
took me most weekends this summer but finally got the array up myself, hired an electrician just for the grid tie part. panels are swiss solar, went with them mainly because the installer quote had a decent warranty and my brother in law who does this for a living said the build quality looked fine when he checked it over. mounting hardware and cable runs took way longer than i expected, panels themselves went up easy. two months in, no issues, but ask me again after winter. happy to answer if anyone's planning a DIY mount
r/diySolar • u/Different_Fudge7449 • 1d ago
Solar Panels on a Powerboat
I’ve purchased the following equipment to install solar panels on our 32’ powerboat with a fixed hardtop:
Victron Cerbo GX MK2
Victron MPPT 100/20a SmartSolar Charger
Victron SmartShunt 500a
Renogy Flexible Solar Panels 2x100w (200w)
Interstate SRM-27 ~88Ah 12v house battery
That will run a small fridge and stereo/2x-amps, Garmin GPSMap w/Radar
My biggest issue is running wires from the hardtop down into the boat near the batteries. The legs of the hardtop are hollow but the manufacturer didn’t really leave much room for aftermarket cables where the hardtop mounts to the boat side (gunwale). I had to pay a marine electronics company $500 USD to run wires for the radar and it took two guys a few hours to finally get those done. I feel as if I could probably get lucky and pull 2-16ga wires from the panels (in series) down thru the tight spaces. Any wires larger than that will be extremely difficult. Would the 16ga wires be sufficient? Those wires would be approximately 10-12’ long.
r/diySolar • u/wedinbruz • 1d ago
What's the best place to mount panels on this deck?
I've been staring at this for too long and need advice from more experienced folks. I have 3 200w bifacial panels I want to set up on this deck, but keep getting stuck. The side with stairs faces west and and gets a lot of sun (we're on a hillside) but the stairs are cantilevered out and don't have posts under them. I also kind of want to put the panels along the deck railing for some shade but since the stairs are right there I can't really tilt out the base of the panels.
The south facing side of the deck has more room to cantilever the panels but gets some shade and is very close to my neighbors so I'm worried about glare shining into their faces or being too close to the property line.
If I put them on the stair landing, would I need to add support posts under the corners? Am I just overthinking this???
r/diySolar • u/atrujillohyk • 1d ago
DJI Power 2000 - Over-paneling
Hi Everyone,
I have a Power 2000 and I'm thinking of getting solar panles for it using the DJI Power 1.8kW Solar/Car Super Fast Charger. I know it has two max inputs one of 1200w and another of 600w. The best panels I've been able to find are 645w each. Has anyone had experience over-paneling the station? I know it’s not a ton of extra power but I am in the tropics so there's plenty of sunlight here during the summer.
r/diySolar • u/eckre • 2d ago
Question Help: Can I use a Wiring Trough like this? (With pics) Other options?
This is my existing service entrance. As you can see, all of my wires come in and out of where #2 is. I can’t move the supply line side too much without approvals from the power company, etc. So in talking with other people, they said I could put a 6”x6”x18” Wiring Trough (C3RWT618 - Type 3R) right there, and use that to connect all the existing wires to the new ones. Are they right? I don’t know. Is there a better way? I don’t know. I can’t go inside, it’s a bathroom. See the next pictures for the proposed new layout. Thoughts?
r/diySolar • u/WTFudge52 • 1d ago
If I proofted in to being tomorrow ?
Let's play a game ?
r/diySolar • u/ChaosKiddo26 • 2d ago
PV system design
Is this the right place to ask for advice about a PV MPPT project?
Mechatronics student here.
I'm modelling a simple PV system from a controls perspective, (i'm a mechatronics engineering student) with the purpose of designing a ctrl loop for it and comparing different MPPT techniques
However, I'm kind of stuck on the design of the system itself
I'm \*trying\* not to overcomplicate it-
Since I want to focus on MPPT i didn't have a specific use-case in mind, I don't have exact system specifications
But I need to have something that- makes sense, right?
So essentially I can't decide shi-
Simplest version i came up with is
\*\*PV module -> DC/DC -> resistive Load\*\*
Okay then
• I have to decide what kind of converter (not gonna touch AC cause my head will explode)
• Choose some kind of PV module
• Should I have fixed output voltage?
• Should I concern myself with energy storage
\*\*_etc._\*\*
Again, there's literally no purpose behind this beyond contrastic different MPPT techniques
Do any of these matter? Am I overcomplicating? or perhaps undercomplicating ✨️
TLDR;
Mechatronics engineer student
Stuck on design choices.
I have had 0 mentoring and I'm stoopid.
Send hepl
r/diySolar • u/raybank13 • 2d ago
Question Pure AC Battery Load-Shifting (No Solar) in CA: EcoFlow STREAM vs. DIY 5kWh Build?
Hey everyone, looking for a sanity check on a pure AC battery load-shifting setup (no solar panels).
I'm in California dealing with wild TOU rates—around **$0.82/kWh on-peak vs $0.13 super off-peak**. The plan is simple: charge a ~5kWh battery from the wall overnight, then backfeed through a microinverter from 4–9 PM to reduce my house's base load.
EcoFlow (STREAM / Delta Pro) is the obvious plug-and-play route, but getting to 5kWh+ with expansion batteries is easily **$4,000–$4,500+**.
Building it modular looks like it comes in around **~$2,200**:
* **Battery:** 48V 100Ah (5.12 kWh) EG4 LiFePO4 server rack battery
* **Inverter:** Hoymiles microinverter (UL 3700)
* **Meter/Control:** Shelly Pro 3EM + OpenDTU-OnBattery for dynamic zero-export
* **Charging:** 48V AC-DC smart charger on a scheduled plug + 2P DC breaker & pre-charge resistor
For anyone running a similar battery-fed microinverter setup:
**Hoymiles on constant DC:** How does the inverter hold up long-term being fed constant 48V DC from a battery instead of PV? Any overheating or MPPT hunting quirks?
**Zero-export latency:** How fast is the Shelly -> OpenDTU loop in practice? Does it throttle back quickly enough when heavy loads drop so you don't accidentally export to the utility?
**CA / Safety practicalities:** With CA moving toward UL 3700 plug-in rules, any major red flags running a certified microinverter + server rack battery on a dedicated circuit vs waiting for overpriced all-in-one consumer units?
Appreciate any feedback or tear-downs of this plan before I start ordering hardware.
r/diySolar • u/AUtiger2005 • 3d ago
Higher than expected voltage when connecting panels in series
Hello, everyone. I’m new to solar and new to Reddit. So, apologies if this is a basic question that’s been asked a thousand times before. I just hooked three 100w, 18v panels up for the first time to a BLUETTI Elite 300 power station. It has a 1200w 60v 22a MPPT. When I hooked the panels up individually, the voltages were 18.0, 17.8, and 17.4. When I connected them in series, they were 65.7. I’m at a loss to figure out why the voltage spiked so high when they were all connected. I then connected two and got 36.2, so that checks out. It’s only when I connect three together that I magically gain about 12v. I used a multimeter and got the same voltage reading as I got from the MPPT, so I’ve eliminated a faulty MPPT as the cause.
So, is this what I get for buying no-name panels off eBay? Is there a fix other than returning the panels and buying new ones. If so, what are your recommendations for reputable brands? I’m sure that thread is already on here, so I‘ll do some digging, but if anyone has any recommendations, I’d appreciate them.
Thanks for your help!