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Data centers are transitioning from AC to DC

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Re: Data centers are transitioning from AC to DC

#272

Earlier quoted context omitted.

Well, having spent some time operating a 12VDC system last year when I moved into some shacks, I will say that I find it a lot more convenient to run 120VAC. I end up converting stuff anyhow, because all my loads run at different voltages- even though I had my lights, vent fan, and heater fans running on 12V I still ended up having to change voltages for most of the loads I wanted to run, or generate a AC to to charg…

Do you have a website with your system on it? I have an off-grid building I need to add solar to in the next year or so. After I fix the foundation and roof, of course. Naturally I’m exploring options for item 387 on the todo list instead of think about how I’m going to jack the building up.

It's a pretty simple system:

4KW of panels, 400W 48V EG4 6000XP charge controller/ inverter 3x EG4 LifePower4 48V batteries a raspberry pi running solar assistant

I feels like a bit overkill, and there is still a whole mppt unused on the 6000xp so I could still double my panel input. Also solar assistant tells me that I rarly go below 75% battery storage. If I just wanted to run my fridge and assorted convenience loads (and ran things like table saws off a generator) then I could get away with a lot less of a system.

But I'm operating a recording studio, and there were a couple days this winter where I had a full-band session and a couple days of storms and got down to below 50%.

Re: Data centers are transitioning from AC to DC

#273

Is there anything left in a modern home that really needs or is better on AC? We have some old ceiling and exhaust fans, but I know those can be replaced. Our refrigerator is AC, but extended family with an off-grid home has a DC refrigerator that cycles way less, probably due to multiple design factors but I’m sure the lack of transformer heat is part of it. I’m not as sure about laundry machine or oven/cooktop opti…

Any appliance with strong motors should be more efficient with AC supply. But almost anything else can be regarded as a heater that doesn't care much as long as it is fed with the correct voltage. Which is actually the core issue.

A DC household would have to choose a trade-off between multiple lines with different voltages or fewer voltages that need to be adapted to the appliances. And we're right back at the AC situation, but worse since DC voltages are more difficult to change.

But consumers like datacenters can very well plan ahead and standardize on a single DC voltage. They already need beefy equipment to deal with interruptions, power sourges, non-sinus components, and brownouts, which already involves transformers, condensators, and DC conversion for battery storage. Therefore almost no additional equipment is required.

Re: Data centers are transitioning from AC to DC

#274
post #214

Earlier quoted context omitted.

That’s still not running out. It’s still there, just more effort to get.

Effort high enough to consider that material lost to any practical purpose like a tv.

Cost scales with refinement effort, so it just results in more expensive TVs. That said, pretty sure we'll have drowned the planet in landfilled TVs long before this becomes a serious issue

Re: Data centers are transitioning from AC to DC

#276

Earlier quoted context omitted.

Whilst I agree that Keanu is a most excellent human, he was hardly responsible for the concept of the Matrix. In my opinion, Philip K Dick was a major influence (I'm a fan and consider him the prophet of the modern age), though Gibson's Neuromancer was likely a big influence too. (Also, there's the old Doctor Who episode "The Deadly Assassin" which features the Matrix). It always seems to me that the far right are be…

> the far right are bereft of original ideas and always co-opt other pre-existing concepts. That's not unique to them: Good artists copy; great artists steal.

"It is only the unimaginative who ever invents. The true artist is known by the use he makes of what he annexes. And he annexes everything."

- Oscar Wilde

Re: Data centers are transitioning from AC to DC

#277
post #266

Is there anything left in a modern home that really needs or is better on AC? We have some old ceiling and exhaust fans, but I know those can be replaced. Our refrigerator is AC, but extended family with an off-grid home has a DC refrigerator that cycles way less, probably due to multiple design factors but I’m sure the lack of transformer heat is part of it. I’m not as sure about laundry machine or oven/cooktop opti…

Of grid homes are vastly more concerned with the energy efficiency of their appliances and thus DC refrigerators generally have more insulation. Most AC customers prefer more internal volume for food over slightly increased efficiency. AC motors are using way more power than the puddly control boards in most home appliances. So you lose a little efficiency on conversion but being 80% efficient doesn’t matter much whe…

I agree with everything you said, except it seems like a false dichotomy. We can clearly build DC refrigerators with more or less insulation. We can clearly build them large or small. If you want to prioritize volume, then surely you could do that with DC. Right?

I know that a long time ago DC-to-DC voltage converters were very large in size, which meant AC would win on space efficiency. But unless I’m mistaken, that’s no longer the case. Wouldn’t a DC refrigerator with equivalent insulation and interior volume have nearly identical exterior dimensions as an AC refrigerator?

Re: Data centers are transitioning from AC to DC

#278
post #160

Earlier quoted context omitted.

Does that mean when we run out of Ga there are no more LED TVs?

Except for gaseous hydrogen and helium, and some spacecraft, all other atoms remain on the earth and are recoverable with enough energy and effort.

One more exception: uranium. It actually splits into smaller atoms when it's used as fuel.

Re: Data centers are transitioning from AC to DC

#279
post #160

Earlier quoted context omitted.

>It is absolutely stupid to talk about this as edisons revenge. If Tesla had the modern high power transistors needed to get high voltage dc out of the ac produced from a spinning turbine he would be all for high voltage dc too. This! The soon people realized these facts the better. The pervasive high rise buildings did not happen before the invention of modern cranes. Exactly twenty years ago I was doing a novel res…

Does that mean when we run out of Ga there are no more LED TVs?

[deleted]

Re: Data centers are transitioning from AC to DC

#280
post #262

Earlier quoted context omitted.

From your earlier comment, your curiosity was more about what happens after we run out. In your question you stated the running out as a given fact ("When" we run out, not "if"). If that was what you wanted to say I can't tell you, but that's definitely how it was received and thus you also got the harsh response. Since it reads a lot like doomsday thinking. (Example: Does that mean when we run out of oxygen there ar…

Yes, my curiosity was about when we run out, because I didn’t know if we would run out. That was the whole point of the question. Have some leniency, we’re not all experts about everything.

> my curiosity was about when we run out, because I didn’t know if we would run out

You still seem to be missing the point.

If you talk about "when we run out", you are presenting yourself as an expert stating "we will run out" and asking about the aftermath.

It would be appropriate, and better received with more leniency, for you to ask whether we would run out.

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