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Comment by ejolto | Hacker News Reader

You should read up on heat pumps, they are several times more efficient than electrical resistance heaters.

26% of heating in Canada is electric baseboard, much of it in buildings that can't or won't allow heat pumps. https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=381002...

Even for those who can, it would take several years for the investment in a heat pump plus the waste of the old heating system to become carbon neutral, let alone cashflow positive.

Don't feel bad. This entire thread is filled with people who think they know better. Must be why UX is in such high demand these days.

I get the enthusiasm though, head pumps are really neat.

Depends on what other value you get from your “heater”. My PC, running at full whack, draws about 700W, which all gets radiated as waste heat. It’s enough to maintain the temperature in my (well-insulated) living room when it’s 20C colder outside.

Still inefficient, but I guess that's power you were going to draw anyway.

You sure it's drawing 700W? Are you running multiple GPUs or what? Is that a server? Have you measured?

That's kinda the point though, that heat is doing work anyway, and they may not have the ability to use/install a heat pump. Of course it would be more efficient, but for example, my condo has three separate electric wall heaters. Instead of using them, we just rely on our computers to heat our space enough. Works until it is about 4-5C outside.

Someday if I ever get to build a custom house, I plan to install a full 42U rack that is tied into the houses central air to optionally heat the house with the waste heat.

Also, if your rig goes over, say, 400 watts of power it is definitely worth it to get an 80+ efficiency rated power supply. There are quite a few tiers, bronze, silver, gold, platinum, titanium, etc., but that's the equivalent of extra 9's uptime where just the 80+ rating is the first 99%

I doubt they use a non-80+ power supply with their modern high end CPU and GPU seeing as the standard was introduced in 2004, with Energy Star certification requiring it in 2006.

But not only is the efficiency rating important but the specific model’s efficiency curves at cold loads and hot loads, 20%, 50%, and 100% loads. Paying attention to your components and what level of power usage they will be at for most of their usage will dictate what the most efficient specific model of power supply (at a reasonable price point for you). This of course makes reviewing and purchasing power supplies quite complicated.

My personal experience has been that people skimp on the power supply, it's the one area where direct performance isn't affected so the features that the power supply provides are not directly correlated to the overall performance of your machine.

Many people, especially in mid-tier or lower builds where every dollar for price vs performance has been calculated to the decimal point will opt for the cheapest power supply that meets the wattage and connector requirements their particular build requires, efficiency and longevity be damned.

My opinion is that getting a guaranteed 80% power conversion efficiency rating (as compared to, say, a 75% conversion efficiency rating) on a 500 watt PC will save you 25 watts of power over the years that you use it, plus a manufacturer that actually goes through the process of getting the approval will probably have also put a little extra care into their manufacturing process and so probably has a better reliability rating than one that did not.

Unless you are scraping to get any PC together it may well be worth an extra $10 in price variance, all other things being equal, for that piece of mind and minor electricity savings to boot.

My point was, in the past few years I have been buying computers, I have never seen a non-80+ psu. Not that they do not exist, certainly there are unlabeled white boxes for dimes and nickels on the dollar compared to a quality one.

I went out of my way to research my current power supply to make sure that given my usage and components, it would operate in peak efficiency (I believe mine is at nearly 95% efficiency at average load, would need to measure it more thoroughly, it has been a few years).

I feel a power supply is like tires. They are the only thing that actually touches the road(electricity). They are worth paying for something halfway decent, not bottom of the barrel.

I do agree, but I would be shocked to see a non-80+ psu at a reputable store like Micro Center.

True. It's been about 5 years since I built a new computer and so my information apparently is a little but outdated, but a quick search through newegg's cheapest power supplies shows things like this:

https://www.newegg.com/p/1HU-0027-00010?Item=9SIAXE5EGG6813&...

650 watt, no-name non-80+ power supply for $40. That's the sort of thing I'm talking about. There are 80+ rated power supplies in the same price range or 80+ from reputable companies for $10 more but it's still a thing worth looking for when you're a newish builder or if you have any concern for the overall efficiency of your computer.

After all, base 80+ rating still means that for every watt your PC actually gets to use you're converting .2 watts directly into heat. That's not a big deal for a workstation that may only draw 100 watts under load but if you have a beefy PC with 3090s and an overclocked 12 series i9 processor with a lot of fans, you could be burning 100 watts or more just to power the thing, so it would definitely be worth it to go for gold or platinum 80+ rating just to save the money in waste heat and in cooling that waste heat after the fact.

RTX3080 and a 12 core i9-12. Yeah, I’m obsessive about power consumption as we’re off-grid - it’s more like 650W at peak, when running a modern game at 4K on maximums. Doing nothing much it draws about 50W.

Got it. Only reason I asked is that I've seen crazy figures thrown around (specially when PSU sizing) that never matched reality - specially when you look at the claimed cooling solutions. Dissipating 700W is no small feat.

Particularly as I have it on a mini-itx, in a cupboard - the radiator lives outside the case, outside the cupboard. It’s actually proven dead handy, as the weather gets too warm for running the log stove, but too cold at night to not have any heating - so using the waste heat from entertainment to keep the place cosy seems like an efficient approach.

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