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Comment promising future for ARM (Score 1) 21

The 'thermal headroom' appears to indicate that ARM CPUs have a lot of room for increasing performance, 'simply' by using more power. The question may be if CPU compute performance will remain the single most important parameter to measure 'bang for the buck', or if memory bandwidth is going to be just as important.

The computing landscape is changing rapidly with the arrival of large language models, but 24+ GB GPUs are way too expensive. It is possible to utilize system memory for running LLMs even today, but memory speed is definitely holding back performance. Thus, multi-channel memory controllers is likely a must even on 'low-end' CPUs if CPU manufacturers are going to remain even slightly relevant in this space.

Comment Re:A: Yay. B: Dang! (Score 1) 90

https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fwiki.pine64.org%2Fwiki%2FO... states:

Network

        2.4GHz 1T1R WiFi 802.11 b/g/n
        Bluetooth 5.2
        Zigbee
        10/100Mbps Ethernet (optional, on expansion board)

But, as others have mentioned.... linux with 64MB RAM? Sounds slightly inadequate....

Comment On the perspectives of meetings (Score 1) 75

To many managers, being present at meetings is their job. It is what they *do*. It is the actual job. To sit in meetings and (presumably) make decisions.

While to the managed, meetings are overhead. It interferes with doing their actual job. They have routines, tasks, jobs, missions whatever. It is a fountain of plenty, and meetings either result in more of the stuff you already don't have time to do, or it is to benefit some other guy.

Meetings are important to some. But so, so much overhead. How many meetings could have been avoided with a phone call, an email, an SMS.

Comment Pros and Cons (Score 1) 350

Pro/Con for hydrogen

Pro:
- potential for long range

Cons:
- no infrastructure in place for distribution of hydrogen for automotive/transportation use
- none of the hydrocarbon infrastructure is reuseable for the purpose of distributing hydrogen. (apart from roads and drivers)
- need space and money to build a completely new hydrogen distribution network, which needs to co-exist with current hydrocarbon distribution systems for year
- compressed hydrogen in confined spaces is a really, really bad idea (garages, tunnels)
- cost of production and distribution of hydrogen cannot compete with ditto for electricity
- wasteful. 2-3 times more energy spent per distance*weight, compared to battery EVs.
- maintenance costs (time and money)
- longevity of tanks and fuel cells unproven

Pro/Con batteries:
Con:
- battery cost
- energy density
- 'refueling' is slower than hydrocarbons/hydrogen

Pros:
- energy distribution network already in place, allows for much better utilization of an already existing (and paid for) infrastructure
- energy efficient
- performance
- potential for utilizing own energy production
- multiple possibilities for utilizing the battery in the car as an energy buffer

Frankly, none of the battery 'cons' carry much weight to me. But they are there.

Hydrogen for personal automotive use is dead, dead, dead. EVs won, get over it.

Hydrogen for long-haul transportation may have a chance. Maybe. But without being propped up with politics, I have serious doubts about the economics of hydrogen as an energy carrier.

Comment Re:Why Hydrogen? (Score 1) 146

Pretty much every serious proposal would use electrolysis to obtain hydrogen. Right now the best electrolyzers are about 85% efficient (compared with the theoretical best) and it's reasonable to expect around 80% efficiency for industrial models.

This is workable, and methane storage can be scaled up much cheaper than batteries. It's not unreasonable to store enough methane on site for several days of autonomous work for a power plant, with batteries it's entirely out of the realm of possible.

80-85% efficient. Provided you can utilize excess heat.
And *then* you need to transport the hydrogen somewhere.

And last but not least, get your energy back from the hydrogen, which carries its own losses. What is a plausible net return of energy with state of the art actual technology these days?

Comment Re:Using hydrogen as an energy carrier is a scam (Score 1) 195

And I claim that we would be better off burning LNG as is, rather than going via hydrogen.

1. The hydrocarbon infrastructure is in place and largely paid for. Hydrogen infrastructure does not exist in the scale we are talking about here. And I am glad that you agree that hydrogen isn't a viable solution, long term.

2. Investing wast amounts of money in infrastructure for hydrogen as an energy carrier ensures that we will have yet another energy carrier to phase out and replace in our lifetime. Much better to invest that money in high voltage lines or batteries or pumped hydro or fucking *anything* useful in a society built for electricity. Building infrastructure for hydrogen in 2019 is mindblowingly short-sighted, unless you're sitting on ginormous amounts of hydrocarbons and have a sinking feeling its value is diminishing day by day.

Converting energy to hydrogen is wasteful. Invest for the future, for long term ROI, and for the environment.

Comment Using hydrogen as an energy carrier is a scam (Score 3, Informative) 195

tl;dr:
Using hydrogen as an energy carrier is a scam, it is stupid and it is wasteful.
Unless you have a very specialized use case.

Let's say you have 1 standard m3 of LNG. That is ~11 MWh of energy.

Spent in a ship engine with 50% efficiency, you get ~5.5 MWh of net propulsion.

Convert the samme Sm3 of LNG to hydrogen via steam reforming, and you get 250kg of hydrogen. Burn that in an engine (at 50% efficiency), and you get ~3.6 MWh net propulsion.

Use 7 MWh of electricity and create 100kg hydrogen via electrolysis, and get 1.5MWh of propulsion.

See a pattern here?

Converting any energy to hydrogen is a lossy process. Then lossy *again* when you spend the hydrogen. The lost energy is lost as heat. *May* be partially recovered via some machinery (requiring space, construction, maintenance, resources and recycling) for *potential* use in some process.

Say you get 80% efficent electrolysis and 65% efficient fuel cells. I believe that is pretty rad tech these days. If what you need in the end is electricity for driving an engine, you just started out by converting half of the energy to heat. Which you need to recover and find use for.

And at the same time: if what you *had* initially was electricity (wind, solar, hydro, nuclear) and what you wanted was heat, a heatpump will return 5x the energy you put into it.

Put 7 MWh (not 11) in a battery, and you get 6,5 MWh of propulsion in an electric engine.
Battery technology is here today providing >6000 cycles, before the battery is down to 90% efficiency.

Hydrogen as an energy carrier does not make the slightest common sense. And I have not even mentioned distribution and storage, for which none of the hydrocarbon infrastructure is reusable. (Apart from drivers and roads.)

Comment emojis.... (Score 4, Insightful) 40

I'll admit to being a relatively old fart. Can someone please ELI5 the industri-wide obsession with emojis? To me, it rates a divison or two lower on "picks my interest"-scale than a new font. And I generally find fonts quite uninteresting. obl xkcd link

No, honestly: I would like to know. I see no innovation in adding more emojis, no basic need covered and it is not as if a world of new possibilities suddenly opens itself because 157 new emojis were added. I am not against the very idea of emojis. I just don't understand the general hype and attention to emojis.

I actually feel a slight bit of secondhand embarassment for this hangup. Is it just me?

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