A grab-bag of viewer follow-ups from my recent builds — including the trick that lets a golf cart battery dump a full kilowatt into a Bluetti like it’s solar.
What I Re-Answered
This Q&A volume pulls together follow-ups from four recent videos: the Bluetti fridge-power “fake solar” hack, the no-name UDPOWER S2400 review, the Mammotion LUBA mini 2 robot mower video, and the mixing-battery-brands video. Rather than re-shoot any of those builds, I’m clarifying the questions that keep landing in the comments and pointing you back to the deep-dive videos in the description for the full walkthroughs.
Why It Works — The Bluetti “Fake Solar” Trick
The most-asked question was about the Bluetti fridge-power unit. Its XT60 DC input accepts 12–60 V at up to 1,000 W. A correctly configured golf cart battery sitting in that voltage window looks like solar to the Bluetti, so it’ll happily pull a continuous 1,000 W from the pack — the maximum the port can take.
The follow-up question was whether you can also dump 2,000 W of solar into that same golf cart battery via an MPPT charge controller while the Bluetti is sipping its 1,000 W. Yes:
- 2,000 W of solar feeds the golf cart battery through the MPPT.
- 1,000 W flows out the other side into the Bluetti.
- The remaining ~1,000 W banks into the golf cart battery for later.
- If the Bluetti is full, the entire 2,000 W stacks into the golf cart battery so it’s ready when the fridge calls for more.
The point of all this is to break past the Bluetti’s 1,000 W solar input ceiling without modifying the unit.
Mini-Split Power — Does the UDPOWER S2400 Work?
Another viewer asked whether the UDPOWER S2400 from my “no-name power station” video could be swapped in for the Bluetti Elite 300 in my hybrid AC mini-split build. Short answer: yes. The S2400 has the same inverter size as the Elite 300 (just a smaller battery), and any power station with at least an 1,800 W inverter is a viable substitute for that mini-split approach. The S2400’s standout trait, by the way, is its UPS — UDPOWER has that part dialed in.
Zero Export and the Plug-In Solar Question
Several of you asked about the elephant in the room with balcony / plug-in solar: zero export. I have a full video on this, but the short version:
- Balcony solar systems do not get reimbursed for exported power right now.
- Some utilities will push back hard if you backfeed.
- Two systems I’ve tested extensively handle this two different ways:
- EcoFlow Stream microinverter — cheaper, but no zero-export feature. Only viable in states (like Utah) that allow a small amount of unmetered backfeed.
- Craftstrom Solar — pricier, but ships with a smart power meter and current sensors that throttle the inverter output before any power leaves the panel. Works in states that haven’t legalized casual backfeed.
If you want the deep dive, watch the full plug-in solar video linked in the YouTube description.
Mixing Old and New Batteries
A viewer asked about paralleling a brand-new LiFePO4 (90–100% capacity) with an old one that’s degraded down to 20–50%. My take: don’t. The resting voltages drift too far apart, and honestly, getting a LiFePO4 cell that degraded is uncommon. A better play is to retire the old battery to a standalone job — solar yard lights, an outdoor project, anything where it can finish its life cycle on its own — and buy a fresh battery to pair with your new one. LiFePO4 prices are low enough that mixing across that big a gap isn’t worth the headache.
What I’m fine with is the realistic case: a brand-new battery paralleled with one that’s been cycling a couple of years and has maybe 10% degradation. The older cell will work a little harder because it’s missing the top end, but the spread isn’t big enough to cause problems at this point in the technology curve.
Robot Mower Overlap
Quick one from the LUBA mini 2 video: yes, the 50–70% overlap you noticed is normal, and there’s an overlap setting in the app. I had mine cranked higher than usual because my grass was extra long.
Pros & Cons of the Fake-Solar Trick
- Pros: breaks past the Bluetti’s 1,000 W solar input ceiling; lets a golf cart battery act as both buffer and “fake solar” source; no modification to the Bluetti.
- Cons: adds an MPPT, a battery bank, and wiring complexity; only worth it if you actually need more than 1,000 W of daytime charging headroom.
When To Use This vs. Alternatives
- Use the fake-solar buffer if you have more solar than your power station’s input can swallow and you don’t want to upsize the unit.
- Skip it if a single power station with a higher native solar input would cover your usage — simpler is better.
- For mini-split runs, pick any 1,800 W+ inverter station; the S2400 is a strong UPS-friendly option.
Bottom line
These Q&A volumes exist because the comments keep surfacing the same sharp follow-ups — and tricks like the Bluetti fake-solar buffer only get more useful when we work through the edge cases together. Keep the questions coming.
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