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kaon_2 | 3 months ago

I worked in this industry as a software developer. Companies like SunCulture (who used to be a customer of ours) started maintaining all their customers on spreadsheets. But with high volume low-value sales, you need to have good software to manage this. We were a player.

I once had to do a mobile money integration with a Zimbabwean bank. A dozen skype calls led to nothing. Then I visited the country, bought a local cell phone, made a few phone calls, and within several days I'd reached the developer I needed. He said: "Wait all I need to do is add this string?". "Yes.". He did so at midnight and our integration worked. Next evening we partied.

It shows how integrations are often more of a human/organizational navigation more than anything technical.

As for the article; the tone is hyped, and it is also somewhat true. Hundreds of millions will be using electricity. Still I want to point out one thing: This is all Solar powered DC electricity. No inverters! So you are looking at powering DC only appliances! Inverters are generally simply too expensive for this. Also the impact on income is very limited; you can't really do anything significantly more productive with the electricity, as several reports have shown. But I don't want to downplay the impact; The quality of life improvement is hard to overstate. Maybe somewhat comparable to say; you are forbidden to use any form of transport (bike, car, bus) to suddenly having all 3. Life becomes so much more convenient. For example: You don't have to take the bus anymore to town to charge your phone - yes people do this.

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jjcob|3 months ago

> 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 offer 1000W power.

amluto|3 months ago

Battery powered induction stoves exist, although they are not cheap enough yet. They are, however, truly excellent products. The one from Impulse Labs is not a case of “wow, I can get decent performance without the monster electric hookup it used to require” — it’s “wow, this seems to be the best stove of any sort on the market by a considerable margin, and it’s nifty that it happens to run off an integral battery, too.” If you’re so inclined, you can cook an entire meal or three on it while unplugged.

If someone wants to make them work in rural areas like this, I think the necessary ingredients will be:

1. Cheaper batteries. These are likely coming.

2. More energy. A meal might require 1 kWh or more. (Or less — scrambled eggs won’t require much energy at all.) This is solvable with more panels.

3. Copper. The coil itself is a decent sized hunk of copper. I assume this is part of why cheap little portable induction cooktops still cost $50 or more.

4. Power electronics? I’m not an expert, and I have no idea how much of the cost comes from the power electronics, but integrating the battery and the induction heater seems like it should result in a dramatically simpler system than, say, producing AC from a battery and then converting that AC into a form that will power the coil. The current list price of the Impulse Labs stove includes a hilariously high power output, and a stove targeting rural Africa could be 1/5 as powerful and would still be fantastic.

I wouldn’t be surprised if someone could squeeze the cost of a decent battery powered stove down to $200 in a few years if they had appropriate scale.

snickmy|3 months ago

AC makes power distribution easier (because you can have modulated phases). So it's correct to say it's easier to move it over a long distance. Additionally, and i'm really simplifying, at parity of nominal voltage, you can move a lot more power, at a lower dissipation cost. This has resulted in few high power electronics to be AC native (ie.: no AC - DC - AC conversion). Think about motors in the various appliances, etc. It doesn't need to be like that, investment in DC car motors have pushed the industry to optimizes design, and get similar power output of the motor at lower energy consumption.

That said, if you are a manufacturer of an appliance and you have an addressable user base of billions with AC, and a 'potential new user base' with DC... you might just want to swallow the cost and add a DC / AC converter for the sake to not have to produce two variants of the most complex / costly item (the motor in this case).

mschuster91|3 months ago

> 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 offer 1000W power.

Your average lead-acid starter battery can easily do that - 1 kW is less than 100 amps at 12V, less than 50A if you wire two in series. 200 Ah means about four hours worth of runtime.

The problem is switching off higher DC voltages and currents. AC is easy, it traverses through 0V 100 (or 120 in the US) times a second. But DC? The arc is just going on. That's why most electrical equipment, from switches over automated breakers to fuses, has distinct ratings for AC and DC, with DC ratings sometimes being half the AC rating.

Additionally, larger DC networks tend to have issues with weird current flows and electrochemical corrosion.

kaon_2|3 months ago

Thought provoking question! I am not an electrical engineer, but arguments I heard went along these lines: Almost all existing appliance markets are AC. Are we really going to be building a complete parallel appliance market? You wouldn't be able to sell a TV from the city in the country side and vice versa. I would be keen to hear what an electrical engineer on hackernews has to say!

Interestingly, when I visited the countryside, I saw some AC electrical appliances. One elder couple had an enormous 80ies style stereo-set gathering dust in the shed. I was told they were a wedding gift.

kragen|3 months ago

Thermal energy storage solves the problem of cooking and washing.

I have a half-liter thermos bottle that leaks about 0.3 watts at ΔT ≈ 50° (635g of water dropped from 71.9° to 69.8° over five hours and 8 minutes), so any power supply averaging over about a watt would be sufficient to boil water in it—eventually. If you needed to do it in the 4 hours the sun was near peak on a single day, you'd need at least 15 watts. (I don't live in Africa, but I do live in a third-world country. Blown-glass thermoses are pretty widely available because, although they're fragile, they're light and never wear out, just shatter.)

Sand batteries are potentially extremely cheap and can easily deliver cooking temperatures. A super-low-tech version of this approach is "salt frying", where you preheat a few kg of table salt (melting point 800.7°) to frying temperature, then stir dry food into it. Most of the salt won't stick to the food, but the few grains that do won't cause the edibility problems that sand would.

TCES potentially offers much greater storage density and much greater controllability than these sensible-heat energy-storage technologies, since you can store the "heat" indefinitely.

Phase-change thermal energy storage is another potentially appealing possibility, potentially offering a stable cooking temperature for many hours, although I don't know of any suitable materials. The MgCl₂-KCl–NaCl eutectic, for example, doesn't melt until 401°. Maybe something like calcium stearate (m.p. 150°–180°) would work, but its heat of fusion isn't great, I'd be worried about long-term stability, and although it's easy to get anywhere in the world, it's probably a lot more expensive than salt. (Table salt is US$100/tonne, but the eutectic mentioned above would be closer to US$400/tonne.)

potato3732842|3 months ago

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 to anything that modulated current flow and has a lot of convenient aspects for motors. Like for like the DC solution costs just a little bit more every step of the way.

Even if you're not doing long distance transmission the cost of all those things that are worse about DC are going to be bore across the entirety of your economy that uses AC. DC makes sense here because the supply chain is so dysfunctional that making the "better" solution work would actually cost more than the "12v doodads from china" style solution. Eventually as electrification continues the choice of DC will become a drag though.

duckmysick|3 months ago

> Companies like SunCulture (who used to be a customer of ours) started maintaining all their customers on spreadsheets. But with high volume low-value sales, you need to have good software to manage this.

That's pretty interesting. Can you tell us more what kind of problems your software solved and how you convinced them to move from the spreadsheets?

I tried something similar (in another industry) and it's a mixed bag. Companies often straight up refuse to move past the spreadsheets even though it creates a significant backlog on their side.

kaon_2|3 months ago

Happy to oblige. Basically we digitized a company from spreadsheets or paper to ERP. We'd introduce accounting software, stock management software, help desk software. But the biggest thing you need is some kind of "Loan Account Management Software" which is the center piece.

This centerpiece tracks the outstanding loan amount that each customer has. It sutomatically sends payment reminder SMS messages a few days before payments are due. It connects to the hardware with internet-of-things to turn it off if payments aren't made. It connects to the bank to ensure payments are there, and confirms when payments are made. Really fun software to build with many different parts.

There were SaaS providers for this. In the beginning (2015) there was only 1 player, Angaza (Reed Hastings mentioned in the article is one of their sales guys). Nowadays there are a handful; PaygOps, BBoX pulse (not sure if that still exists), and a few smaller ones. They charge like $2-$7 per device managed on the platform.

Convincing customer to take this up was not hard at all. You pretty much needed it to run your operations on anything more than 100 customers, and as the above article shows, scale had big advantages. Moreover; if you could show to investors that you had the software infrastructure scale, they were significantly likely to give money. It was boom time until corona hit. Everyone was expecting 30% YoY growth like until 2019, but then everything stagnated. Many companies went bankrupt and a lot of consolidation happened in the distributor market. Companies saved money on their software first, and we called it a day.

In the manufacturing industry where I am now, I fully agree with the mixed bag. Companies are old, with many old people, they stay small and don't necessarily need to scale or "grow forever". They are conservative and happy with the way things are.

chrneu|3 months ago

My understanding is that the main benefit of small solar like this is to get combustion out of the home, specifically kerosene or dung lamps/stoves. A lot of folks have respiratory issues because they cook indoors.

kaon_2|3 months ago

Yes and no. You are right that indoor cooking (or outdoor on wood) is indeed one of the biggest causes of death worldwide. It dwarfs deaths by malaria. And where people don't die, it causes respiratory issues. I don't know the math but it is similar to smoking X cigarettes a day.

- sidenote - You always learn that in centuries past, people didn't grow old. I never knew why but my current suspicion is that air pollution by stoves and hearths was probably the top 3 cause.

However, cooking isn't (yet) solved by solar. Making heat from electricity is hard! Clean Cooking solutions often use propane, butane, or wooden pallets. Clean Cooking companies face all of the same issues as the Off grid solar companies of this article. But you'd be surprised that it is really considered a different industry. Customers and price plans are the same, but funding often comes from different sources.

Making affordable, electric, clean cooking solutions would be one of the most impactful inventions of our generation. Even then, challenges remain: No cultural activity is as steeped in tradition as cooking, and convincing people to change this, resulting in different tasting meals, is hard. Particular if it is the man deciding on the money, and the woman doing the work.

veunes|3 months ago

Totally agree on the DC limitation point too. A lot of folks outside the space assume these systems are just mini-versions of Western home solar setups, but they're not