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Slow Electricity: The Return of DC Power? (2016)

lowtechmagazine.com

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Re: Slow Electricity: The Return of DC Power? (2016)

#151

Post by hippari »

hutzlibu wrote: post #113
function_seven wrote: post #44

Earlier quoted context omitted.

I get unreasonably angry when Victorian cosplayers think they've found the solution to our wasteful modern life. Simply eschew modern conveniences and spend hours each week beating your clothes against a rock! Simple , instead of grocery shopping twice a month, ditch that wasteful freezer and walk to the farmers' market down the block before dinner each night. Was it cloudy yesterday? Simple! , take a whore-bath¹ at…

"Simply eschew modern conveniences and spend hours each week beating your clothes against a rock" My question is, if those people actually tried that by themself before suggesting it, or if they just picture the women doing it somewhere. I mean in this specific instance I can imagine they tried. And I did too, while off grid. It gives you a special connection to your clothes. But suggesting this as a general way of l…

I grew up doing all of those by hands, with the exception of washing machine, I still do all of those chores by hands now.

And I'm still only in early 20s, not some old dudes.

We debloating our computers all the time, so what's wrong with debloating our houses, and our life ?

Re: Slow Electricity: The Return of DC Power? (2016)

#152

Post by nine_k »

function_seven wrote: post #44
IlliOnato wrote: post #37

I read the whole article with sympathetic interest, until the conclusion: > One way to solve the problem of high power devices is simply not to use them -- this is the approach that's followed in sailboats, motorhomes and caravans > Obviously, this strategy implies a change in our way of life. It would mean that electricity is used only for lighting, electronics and refrigeration, while non-electric alternatives are…

I get unreasonably angry when Victorian cosplayers think they've found the solution to our wasteful modern life. Simply eschew modern conveniences and spend hours each week beating your clothes against a rock! Simple , instead of grocery shopping twice a month, ditch that wasteful freezer and walk to the farmers' market down the block before dinner each night. Was it cloudy yesterday? Simple! , take a whore-bath¹ at…

Simplicity is not a synonym of ease; very often it's an opposite.

Making something both simple and easy is a highly sought art.

Re: Slow Electricity: The Return of DC Power? (2016)

#153

Post by zo1 »

Gibbon1 wrote: post #126
Karrot_Kream wrote: post #83

Earlier quoted context omitted.

An induction hob with a single ring/burner takes anywhere from 1.3-1.8 kWh of energy. It's almost impossible for the type of person that would benefit from a rocket stove to have access to a solar setup which could generate that much energy. Moreover, most of the time these families/individuals are impoverished enough and/or live in places with bad enough infrastructure that even gas for a gas stove isn't available.…

Run the numbers. 400-500W of solar provides enough energy per day. Two 150ah batteries can handle the peak load.

I live in, arguably a good part of Africa, and even here it would be a stretch. Infrastructure and "throw money at the problem" type solutions don't work great in rural areas even if you have local communities buy in and assistance.

You're better off just giving poor people here free electricity, which a lot of places do.

Re: Slow Electricity: The Return of DC Power? (2016)

#154

Post by upofadown »

throw0101a wrote: post #139
klondike_ wrote: post #85

DC wiring is already standard in many office buildings in the form of power over Ethernet (PoE). It powers access points, lighting, and infrastructure, and high power variants can do 100W+. Since it's under 50V, the IT guy can install it without a qualified electrician. High power loads like motors and heaters will continue to require AC but I see no reason why small loads can't use PoE. I would love to see it take o…

> It powers access points, lighting, and infrastructure, and high power variants can do 100W+. 802.3bt Type 4 allows for sending 100W down Cat 6A cables, but only 71W is available at the other end. That's highly inefficient. * https://en.wikipedia.org/wiki/Power_over_Ethernet#Standard_i...

The loss is proportional to the length and ethernet cables are usually much shorter than the maximum length allowed by the standard.

Re: Slow Electricity: The Return of DC Power? (2016)

#155

Post by hippari »

dijit wrote: post #134
JohnWhigham wrote: post #124

Earlier quoted context omitted.

If you're careful about water usage and use cold water, you'll always beat a dishwasher. Another thing people often forget about dishwashers: you're supposed to pre-scrub the hard shit off the dishes. Well, you just did half the mechanical work yourself, why not finish it? I think part of it can also be (at least for me) upbringing. We always handwashed our dishes, and only used the dishwasher a couple times per year…

I grew up handwashing too but I disagree with your assertion. Firstly, you can't wash with cold water because soap doesn't activate with cold water, hot water also kills bacteria and helps cut through grease. Fats themselves are hydrophobic and without activated soap you wont get them off... enjoy your "filmy" dishes. Second, humans expend a lot more energy than you think. The act of standing and using our arms relea…

Human body will have to expense energy regardless whether you do it with house chores, or going to the gym, or a walk in the park.

Re: Slow Electricity: The Return of DC Power? (2016)

#156

Post by hippari »

function_seven wrote: post #44
IlliOnato wrote: post #37

I read the whole article with sympathetic interest, until the conclusion: > One way to solve the problem of high power devices is simply not to use them -- this is the approach that's followed in sailboats, motorhomes and caravans > Obviously, this strategy implies a change in our way of life. It would mean that electricity is used only for lighting, electronics and refrigeration, while non-electric alternatives are…

I get unreasonably angry when Victorian cosplayers think they've found the solution to our wasteful modern life. Simply eschew modern conveniences and spend hours each week beating your clothes against a rock! Simple , instead of grocery shopping twice a month, ditch that wasteful freezer and walk to the farmers' market down the block before dinner each night. Was it cloudy yesterday? Simple! , take a whore-bath¹ at…

Victorian ? Where I'm living that's what most people do ( well except for the washing machine ).

I think the same applied for the majority of population in underdeveloped / developing countries.

Re: Slow Electricity: The Return of DC Power? (2016)

#157

Post by lbriner »

pomian wrote: post #12
monitron wrote: post #3

We're currently in the process of designing a house that we hope to build early next year. One thing that I dream of doing is lighting the entire house with LEDs wired in a low voltage DC "network." Even better if they're addressable, dimmable, even RGB recolorable. Power over Ethernet would be a pretty cool way of doing it if it was practical...that way you get the data to control the lights as well as the power to…

Look into country cabins, boats and campers. Especially the first though. Many are built with only solar for power. They have 12 volt wiring for 12v lights, and 12v outlets. The only AC is if someone plugs in an inverter to a 12v outlet. If course there are many builds with a main inverter next to the ' battery shack', and often 110 AC wiring from that. But there is a lot of information about pure 12v systems, and it…

That isn't a great analogy because the expectation for electrical appliances in a boat/camper/cabin is much lower than it would be in most homes.

I had a battery fridge in a caravan (trailer) and it was very small and pretty rubbish, certainly not suitable for home. However, for a short stay, it could keep some basic foods cool enough to be safe.

As others have said, although it is fine on paper, as soon as you start talking about significant power, you are talking lots of amps, which means more risk of overheating and fire, potentially significantly larger (and therefore expensive) cabling and all of the switchgear that can support a few amps AC will not support the same current at DC so all your switchers are larger/electronic. There is also an issue of RFI which could be significant if you are switching high current DC loads.

Re: Slow Electricity: The Return of DC Power? (2016)

#158

Post by hippari »

spijdar wrote: post #98
nielsbot wrote: post #93

Earlier quoted context omitted.

Can you explain how dish washers are more efficient than hand washing? Is it about water use? What if you don’t run the water while you soap your dishes and only rinse them in a rinse tub?

I haven't watched this video in a while so apologies if it's not specifically elaborated on, but I believe it's covered here: https://youtu.be/_rBO8neWw04 From memory yes, it's partially about water usage, but dishwashers are in general just pretty good overall about efficiently using energy to maximize "food grime removed" per unit of resources fed in. Even if you're careful with water usage while hand washing, I th…

You have to heat water to wash your dishes ? What kind of gravy sauce are you cooking in your pot.

Re: Slow Electricity: The Return of DC Power? (2016)

#159

Post by lbriner »

Robotbeat wrote: post #31
bombcar wrote: post #26

Earlier quoted context omitted.

Yeah I seem to recall that many extremely high voltage long distance lines are actually DC

Indeed. This is because you get phase differences (due to finite speed of signal in wire, even though it's near c) over those distances. Converting to DC and then back to AC at the destination avoids any concern about phase mismatch.

It isn't just that. afaik, a much larger issue is related to capacitive and inductive losses of AC. Even on the railways, an adjacent 25KV overhead line can induce a few hundred volts into the adjacent "dead" line, which is why they must be earthed before you can work on them.

Re: Slow Electricity: The Return of DC Power? (2016)

#160

Post by lbriner »

zurn wrote: post #68

Many of the loads discussed, eg washing machines, are also reasonable matches a local solar power source, as it's much cheaper to buffer hot water than have large batteries. (Water heating dominates the energy used in those, the mechanical sloshing around takes trivial power compared to it).

And what do you do for the 6 months of the year when there is not enough solar to heat water to a suitable temperature?
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