Can a "Solar power stations" be used as a UPS for a Server Rack?

I know that typical convention is to opt for reliability with conventional brands. However outside USA options for UPS can feel rather dated.

  • Lack of “LiFePO4” or “Li-ion” options (10 year battery replacements!), most are lead-acid battery based - especially past the 2kw level
  • Lack of alternative power inputs (Solar, etc)
  • Much higher price point (especially past the 2kw level)

Some “Solar Power Stations” include UPS options, so on paper it make sense. The only down side is the inability to rackmount. So for example…

  • The “Best li-ion” option from APC : APC Smart-UPS, Line Interactive, 3kVA

    • Max: 2700 W
    • Capacity: 2.88kVA
    • Cost: US$3,675 (before availability markup)
    • Battery type: Li-ion
    • Nearly impossible to find in some regions (including where I am)
  • EcoFlow Delta Pro

    • Max: 3600W
    • Capacity: 3600Wh
    • Cost: US$3,599
    • Battery type: LiFePO4

From what I understand Wh, and VA is interchangeable (i might be wrong)

The only main downsides I can find is : Switch over time is 20ms, APC maxes 10ms

However if “switchover time” is an issue, we can choose to run the “Power Station” in “on-line” mode. Where no switchover occurs : it still considerably competitive in price to value.

Wierd sizing be damn - Am I missing something? Or is this a case of, it aint broke dun fix it.

PS: I really want competition in the UPS space

PS: I really want competition in the UPS space

Relevant to your interests, this guy DIY’d his: https://xtremeownage.com/2021/06/12/portable-2-4kwh-power-supply-ups/

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Gotta love how ridiculously thick the power cord is (for good reason though!)

While not directly related, I am building a solar UPS with off the shelf parts.
Got a 2400w all in one charge controller, inverter, and transfer switch, 8x 395w panels, a combiner, and a pair of massive 3 KWh lead salt batteries.
total cost before the panel install was ~$4700

I have tested the low battery auto transfer to be 5-8ms on the controller I got.

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5-8ms is significant.

I could not fact check it, but many were loosely citing the ATX spec of 16ms. Which make the 20ms switch potentially an issue.

However I suspect the 20ms switch statement is more of them being safe on the legal side, and not actual benchmarks (as their target audience probably do not care as much).

What inverter and “transfer switch” you using? I would like to dive more into this.

There is. In fact, this manufacturer lists the top 10, themselves ranked #6, on their site:

For security reasons, some may choose to avoid certain vendors on that list, but there’s still plenty to choose from.

A few more things:

  • if fast switch-over is important for your equipment, use a online/double-conversion type UPS. The Wiki page explains more on the various differences.
  • if your company relies on a UPS to keep their data safe, do NOT do a DIY job, get a ready-to-run device instead. This is especially true if the DIY-creators/builders are more knowledgeable on PHP and/or network packages then Amps and wire resistance. A (faulty) 12V battery can easily kill you, if circumstances are right. Volts hurt (usually), Amps kill :roll_eyes:
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I have a MPP Solar LV2424. I’m using it more as an always online system, because the only time line power will be used is if there is no sun for a few days. The switch time is only a factor if you bypass the inverter, otherwise it just runs a charger and the inverter never shuts down.

My goal was to have my rack running only on solar power 90% of the time, being a UPS is just a nice secondary thing. Edit: also having the ability to run my freezer and well pump when the power is out were the other goals

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Might be a market segment issue then. In South-East-Asia, suppliers only seem to stock

  • APC (Schneider Electric)
  • ProLink

With higher end models being “on demand” - with long ETA due to supply chain issues.

To clarify exploring for home rack usage - my company DC providers already handles this. So I guess im ok with some non-fatal failures :sweat_smile: in my use case

But yea, even though i done EE in school. I heavily prefer the “Power Stations” over the DIY route, as I really do not want to be dealing with expose wires that may run 2kw, so would definitely get an electrician if it ends up that route.

As of now, the out of box nature of EcoFlow appeals to me in this regards.

Ahhh, any issues with your rack in that case? or does it “just work”.

Similar train of thought for me, as I am aiming to first try to offset energy consumption on peak sunlight mid-day. Before considering scaling up.

Due to my apartment location, I highly doubt I can scale any higher (due to blockage from other buildings, etc)

For the most part it “just works”.
everything I’m running right now works out to about 400w continues, and when my storage box has all disks spinning add another 200w to that. If I get good sun for more than 8 hours it will make it all night without using line power.

This has lead me down the path of optimizing for power use and having things spin down when not needed. I have swapped my unraid boxes CPU for a T variant, added a GPU for plex to encode, moved my always running network service stuff to a jailbroken chromebox that only uses 6 watts, and got 80+ platinum PSUs that hit peak efficiency at the typical load levels

As for the area, I have 16 sqm of panels total on a south facing roof. The rated capacity of the panels is just about 3200w but because of the angle and the latitude I’m at it peaks at a theatrical 2600w.

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I just spaced out a solar system for a client to run a rack with a security system. Depending on options for 24/7/365 operation with 24/hrs of batter backup it came out to $12k on the low end to $35k on the high end.

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Ive been thinking about building a shed and putting a solar setup on it… and moving my homealb stuff into it.

Dew it

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Depending on your locality it is considered “low voltage” and doesn’t require permitting or licensing to install it. Just don’t touch the black wire to the red one :wink:

as long as i dont try to grid tie… i should be fine.

i hear

Grid tie for battery charging and bypass is fine, its the feedback to the grid that will get you in trouble if you don’t get a certified inverter, you don’t have a professional installer, or your local utility co does not have meters/a program for it.

I think a UPS that is dependant on good weather would defeat the point.

Its going to depend on what controller is used, but in my case I have it set to transfer to grid power if the batteries fall under 35%. At that point there is still another 3-4 hours of runtime on my rack if I don’t shed any load and the grid power drops out.

You only need an electrician to hook it up not do the entire installation. So you can do all of the infrastructure and just pay an electrician for an hour to literally just plug it into the grid.

VA and W are interchangeable for DC or AC power with a power factor of 1.0 and are measuring power. Wh is a measure of total energy stored (power times time, or over a length of time).