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Solarpunk is happening in Africa

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Re: Solarpunk is happening in Africa

#611

Post by kragen »

potato3732842 wrote: post #453
jjcob wrote: post #413

Earlier quoted context omitted.

> So you are looking at powering DC only appliances! Is there anything you actually need AC for? The big advantage of AC is that you can easily transform it for long range transmission. If you don't need that, AC is not really necessary, is it? I guess the bigger issue is the limited power -- you probably can't use a small scale solar installation for cooking or washing, not because it's DC, but because it just wont…

Ignoring the cost of the battery how much does a cordless drill that'll break your wrist cost? A non-trivial amount more than the corded one that's for sure. You're gonna see comparable cost difference in just about every "final appliance" that actually turns the jiggling electrons into results (whether those results are work or heat). Alternating current is substantially easier to step up/down in voltage, much nicer…

I don't think this is correct. Drills use "universal" motors which don't care if they're running on AC or DC, because 60Hz AC motors are limited to 3600rpm, which isn't nearly fast enough for a drill, and also because it's not okay if the drill stops working if it hits resistance and slows down. (Most AC motors run at a fraction of that.) You can run a cheap electric drill off 120Vdc just as easily as 120Vac. Getting it to run on 48Vdc or 30Vdc involves rewinding the motor with the same amount of copper in the form of thicker wire.

Fancy drills already have a lot of electronics that do care about the polarity of the applied voltage, but they usually want it to be DC. Once you get anything more sophisticated than phase-angle control with a TRIAC, you're using MOSFETs anyway, and you can often use half as many of them if you're using DC, because MOSFETs like DC.

Re: Solarpunk is happening in Africa

#612

Post by ViewTrick1002 »

mensetmanusman wrote: post #594
ViewTrick1002 wrote: post #575

Earlier quoted context omitted.

That is construction of new plants. In terms of actual coal burned in those and already existing plants it is declining.

China burned more coal at power plants between January and July of 2025 than at any time since 2016. https://www.realclearenergy.org/2025/08/29/china_burning_coa...

I think you should find authoritative sources rather than relying on blogspam misrepresenting the source article.

Your article is a single paragraph:

> China burned more coal at power plants between January and July of 2025 than at any time since 2016, despite massive renewable capacity, according to new environmental research report.

Then they link the source DW article:

https://www.dw.com/en/china-boosting-coal-capacity-at-record...

Which was updated due to not correctly presenting the underlying report.

> Correction: The article initially referred to China burning coal at record high levels and had other inconsistencies with the original CREA report. This has been edited to reflect that the study highlighted an increase in coal power plants, rather than burned coal, after being contacted by the research institution.

Which is what I have been telling you again and again. China is building tons of coal plants but in absolute terms the coal usage is declining.

Why is it so hard to accept that?

Re: Solarpunk is happening in Africa

#613

Post by jodrellblank »

ethbr1 wrote: post #604
jodrellblank wrote: post #596

Earlier quoted context omitted.

> so about 0.5kwh It takes 1.16 Watt-hours to raise a litre of water by a degree. Say 85Wh for 15C room temp to 100C boiling. Assuming your large meal for three is 3 litres, that's 255Wh to get the water boiling. There's energy loss from battery through inverter, through induction. Loss in the pot losing heat to the air. This doesn't count keeping it simmering, or heating the other ingredients. I don't have any idea…

> 'pot cosy' to insulate the pot and stop radiated heat loss Is this a product that exists? The closest I could find was ceramic fiber insulation [0], which could presumably be cut to shape and fastened (high temp fastener?) into pot shape. [0] https://www.amazon.com/s?k=ceramic+fiber+insulation

Yessss, more or less. I learned of the idea from this guy's content[1] who bikepacks ultralight and wants to save camping stove fuel, and he made his own. And from my dad who habitually wraps a thick teatowel around stew pots, on principle (he doesn't measure for a difference in power use. Electric cooktops only, not flame ones). Since it has to be snug on the pot, making one is probably the common way forward.

A few products do exist in that ultralight camping world, the Toaks D95 Pot Pocket[2], the Trangia Pot Cozy[3], Glacier Minimalist "pot with insulating sleeves". In standard size maybe the "So-Vida Sous Vide Insulation Band and Mat for Pots - Protects Your Work Surfaces and Saves You Electricity From Increased Insulation"[5] which is out of stock.

The Wonderbag[6] marketed as for communities in Africa and not available in the USA. From the Wikipedia page on Thermal Cooking[7], in a normal size kitchen people probably go with a vacuum flask cooker, popular in Asia.

[1] https://www.tristanridley.com/post/2019/01/21/diy-pot-cosy-t...

[2] https://www.toaksoutdoor.com/products/coz-m

[3] https://trangia.se/en/shop/pot-cozy/

[4] https://gsioutdoors.com/products/glacier-minimalist

[5] https://www.amazon.com/stores/SO-VIDA/page/BB00BAE8-07C8-4B4...

[6] https://en.wikipedia.org/wiki/Wonderbag

[7] https://en.wikipedia.org/wiki/Thermal_cooking

Re: Solarpunk is happening in Africa

#614

Post by lambdaone »

Ray20 wrote: post #357
lambdaone wrote: post #199

There's also nothing stopping African communities from building peer-to-peer microgrids if they want to.

The same thing that's, you know, stopping them from having real power grids.

A microgrid lets you power your neighbors, or receive power from them.

This paper cites several examples of peer-to-peer electricity trading: https://www.sciencedirect.com/science/article/pii/S030626191...

Re: Solarpunk is happening in Africa

#615

Post by [deleted] »

prmph wrote: post #599
ta20240528 wrote: post #597

Earlier quoted context omitted.

No, I'm saying their/our societies are broken. Wrong values, wrong incentives w.r.t. to the skills required to build modern, well-maintained cities with roads, schools, hospitals, etc. when compared to similar peers in e.g. Asia. Of course they are intellectually capable of laying asphalt, but they end up spending it on salaries, ridiculously enriching small elites, etc. Its not unique to Africa, but its certainly en…

> Wrong values, wrong incentives > Of course they are intellectually capable of laying asphalt, but they end up spending it on salaries. > Only one decided it was important for their families and grandchildren to pour said asphalt. Are these statements not supporting what I originally said: that there is a difference between ability and motivation?

[deleted]

Re: Solarpunk is happening in Africa

#616

Post by gffrd »

typpilol wrote: post #317
gffrd wrote: post #296

Earlier quoted context omitted.

I believe Parent is talking about trust in the ability to deliver on promises, not in handling of IP.

Oh I agree. But I'd say trust is the wrong word They're reliable, but would you really trust them? I think there's a bit of nuance there to differentiate the 2 though. Maybe I'm jaded from working with overseas factories though in ways others wouldn't be.

That's a good clarification.

Trust implies shared values/worldview and past experiences where outcomes match expectations. Also respect.

Trust is not possible when there are regularly incongruous outcomes, or where definition of respect / values are just aren't aligned.

Do you think your counterparts overseas believe themselves to be as trustable as you are, and it's just a cultural rift? Or is that too charitable?

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