DC-AC-DC-AC-DC Conversion Loss for Computers/Electronics

Is there a way to avoid all this wasteful conversion? You've got solar panels sending DC to an inverter, which converts to AC, goes into the breaker, to the outlet where my server rack UPS is plugged in, which converts to DC for UPS battery storage. When the power goes out, the UPS converts DC battery to AC to the servers' power supply, ultimately converting back to DC to run the servers.

1) If I have solar+batteries, do I still need the UPS? I can monitor the UPS and automatically shut down the server once 50% of the battery is gone.
2) Can I run DC to my outlets and swap out a DC-DC power supply in the server?

I do that with a washing machine using a modified inverter. Panels go right int the inverter high voltage section. It is very efficient. When a cloud passes the high voltage boost section of the inverter turns on just enough to make up lost power and responds instantly. There are some that do this same blending with inverter AC. It is pretty neat to watch. I don't know what people do at BINsolar (buy it now), I only do DIY.

I have a similar question, but for charging batteries for tools, ebikes, etc.

I have a Lectric bike and asked Lectric if they could produce a DC to DC charger with a solar controller. They wrote back and said they would pass along the idea. I am not holding my breath.

But is there a DIY solution?

I did find a couple of YouTube videos on YT, but not specific to Lectric, and nothing here on DIYSolar (well, this thread).

If the charger is an SMPS, it likely rectifies 120Vrms to 170VDC, then bucks that down to desired voltage.

You could select a series string of PV panels that won't deliver excessive Voc (even in cold weather) and try feeding that directly to the DC bus, or through the AC pins. Needs to be oversize PV array, will not have MPPT function (so you'll waste a lot of watts, but get simplicity.

We've successfully fed DC into SMPS, even PF corrected ones.

They often contain fuses or breakers, rated for AC. Best if you replace that with suitably DC rated ones.

Oh, and even more reason to do your charging where it can't burn the house down.

DrewLoker said:

I have a similar question, but for charging batteries for tools, ebikes, etc.

I have a Lectric bike and asked Lectric if they could produce a DC to DC charger with a solar controller. They wrote back and said they would pass along the idea. I am not holding my breath.

But is there a DIY solution?

I did find a couple of YouTube videos on YT, but not specific to Lectric, and nothing here on DIYSolar (well, this thread).

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Charger is 54.6v @ 2 amps. Might be able to use standard 48v solar stuff.

I usually see multiple contacts for lithium tool chargers. In some cases that may be per-cell contacts, others could be communications including temperature.

I think that is definitely "Danger Zone!" if you connect foreign charging equipment to the battery. I'd rather let the matching charger handle it, just feed it something other than the A/C it was looking for.