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How I Gave Up Alternating Current

robrhinehart.com

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Re: How I Gave Up Alternating Current

#81

Post by rtkwe »

54mf wrote: post #56

"For storage a $65 lead acid automobile battery does the trick. It’s 12V so can be charged directly from the solar panel, and holds 420Wh, way more than I use in a day. That’s $0.15 / Wh so I don’t see why everyone is so excited about Tesla charging $0.43 / Wh for the Powerwall, sans inverter and installation." I'm not smart enough to take this apart, but my gut tells me the best-in-class engineers and (tens/hundreds…

That battery has very poor deep cycle and recharging characteristics. Standard lead acid car batteries don't like being discharged below ~50% like others have pointed out. Because of this the battery is going to lose most of it's capacity quickly and need to be replaced long before practically any other choice, there are lead acid batteries called deep-cycle that are designed to be drained and recharged.

Like most things you can slap together something that works on the surface much cheaper in initial costs than the commercial equivalent.

Re: How I Gave Up Alternating Current

#82

Post by david-given »

dragontamer wrote: post #68
david-given wrote: post #63

Earlier quoted context omitted.

Hmm. A washing machine consumes about 100Wh == 360kJ for a load (ref: http://www.rpc.com.au/information/faq/power-consumption/wash... ). The Emma Mearsk, one of the largest container ships around, uses 13 tonnes of fuel an hour to transport 18000 containers, over a distance of (say) 20000 kilometres, which is 1kg of fuel to transport one container 45km (according to Wikipedia: https://en.wikipedia.org/wiki/Energy_eff…

Shipping is always surprisingly cheap. But manufacturing new clothes every time you need new clothes? In China, land of the "who cares about the EPA" coal-laden environmental almost-slave-labor disaster? Built from synthetics (which are Petroleum-derived) ? To add insult to injury, he talks about injuries / deaths from HEPPA-regulated American Power Plants without giving a damn about the suicide nets placed outside o…

I don't know, how much energy does making clothes in China consume? You're more than welcome to go find out and let us know...

Re: How I Gave Up Alternating Current

#83

Post by megalodon »

david-given wrote: post #63
justinph wrote: post #4

Interesting, but it seems like a lot of the lifestyle choices are just pushing the carbon/climate impact to someone else where the author doesn't have to think about it. Getting custom clothes made in china and shipped frequently is certainly far less environmentally friendly than simply re-using the clothes you already have. Taking an uber still burns gasoline. A bike would be better.

Hmm. A washing machine consumes about 100Wh == 360kJ for a load (ref: http://www.rpc.com.au/information/faq/power-consumption/wash... ). The Emma Mearsk, one of the largest container ships around, uses 13 tonnes of fuel an hour to transport 18000 containers, over a distance of (say) 20000 kilometres, which is 1kg of fuel to transport one container 45km (according to Wikipedia: https://en.wikipedia.org/wiki/Energy_eff…

I fail to see how this makes the article plausible.

Re: How I Gave Up Alternating Current

#84

Post by david-given »

maxerickson wrote: post #71
david-given wrote: post #63

Earlier quoted context omitted.

Hmm. A washing machine consumes about 100Wh == 360kJ for a load (ref: http://www.rpc.com.au/information/faq/power-consumption/wash... ). The Emma Mearsk, one of the largest container ships around, uses 13 tonnes of fuel an hour to transport 18000 containers, over a distance of (say) 20000 kilometres, which is 1kg of fuel to transport one container 45km (according to Wikipedia: https://en.wikipedia.org/wiki/Energy_eff…

360 KJ is 0.1 KW-h. So it would be 1.5 cents, not 15.

You're absolutely right. I'll update the post.

Also, we seem to have killed the US Energy Information and Administration energy prices website. I feel that my day is now fulfilled.

Re: How I Gave Up Alternating Current

#85

Post by maxerickson »

david-given wrote: post #84
maxerickson wrote: post #71

Earlier quoted context omitted.

360 KJ is 0.1 KW-h. So it would be 1.5 cents, not 15.

You're absolutely right. I'll update the post. Also, we seem to have killed the US Energy Information and Administration energy prices website. I feel that my day is now fulfilled.

You have an incorrect period at the end of the link.

Re: How I Gave Up Alternating Current

#86

Post by dragontamer »

david-given wrote: post #82
dragontamer wrote: post #68

Earlier quoted context omitted.

Shipping is always surprisingly cheap. But manufacturing new clothes every time you need new clothes? In China, land of the "who cares about the EPA" coal-laden environmental almost-slave-labor disaster? Built from synthetics (which are Petroleum-derived) ? To add insult to injury, he talks about injuries / deaths from HEPPA-regulated American Power Plants without giving a damn about the suicide nets placed outside o…

I don't know, how much energy does making clothes in China consume? You're more than welcome to go find out and let us know...

My post was less about the energy usage and more about the Sweatshop workers's working conditions.

He seems concerned about highly-paid Energy Workers in the US who are required (by law) to have safe working conditions (or at least, safe as defined by the law. People still die on the job but at least we try to keep them safe).

And then he turns around and brags about using cheap Chinese workers to sew him new clothes every week. Hypocrisy at its finest.

Re: How I Gave Up Alternating Current

#87

Post by marcosdumay »

teamonkey wrote: post #46
wklauss wrote: post #30

I have long wanted to fully switch to DC in my life and would love to see common appliances designed for a DC world. It's a shame that the opportunity to discuss this is lost in this post because of the pedantic tone of the author. Phrases like "I think it was a bit presumptuous for the architect to assume I wanted a kitchen with my apartment and make me pay for it" or "I don’t want to live with red hot heating eleme…

Just what practical options are currently available? With roof-mounted solar panels becoming commonplace (at least where I live) it seems like 12V DC is a practical target, but it irks me that it gets converted to AC before being reconverted back to DC by a wall wart a few meters away.

Well, 12V is really wasteful. Placing an inverter in the loop is probably cheaper and more efficient than routing 12V electricity though one's house.

Re: How I Gave Up Alternating Current

#88

Post by mindslight »

wklauss wrote: post #77
teamonkey wrote: post #46

Earlier quoted context omitted.

Just what practical options are currently available? With roof-mounted solar panels becoming commonplace (at least where I live) it seems like 12V DC is a practical target, but it irks me that it gets converted to AC before being reconverted back to DC by a wall wart a few meters away.

That's the problem, there are not many (some fridges designed to be operated from car plugs, camping gear, things like that) and often is just an appliance that has a converter inside, so it is as inefficient as you'd expect. Not sure if there's a way to design stoves, fridges, ovens and washing machines powerful enough just using DC, though.

For stoves/ovens, just up it to 240V DC. They're just big resistors and will work basically the same (although mechanical power switches will wear out quicker, and now that I think more, triac-based ones may not turn off at all).

Things could get really interesting if say the EU started incorporating a requirement for things that should essentially run fine on DC to compatible with DC. Universal power supplies (computers, phone chargers, etc) and brushless motors (washing machines) should really only require tweaks of their control circuits. AC motors (fridges/dryers/air conditioners) and microwaves wouldn't be an easy change. They'd either need a local converter or for demand to ramp up for explicit DC versions.

Standby power supplies (the thing that powers the IR receiver and power button while your TV is "off") wouldn't function as-is, since the common method is to use a capacitor+zener across the power line. But changing that to a rectifier + small switcher doesn't seem terribly onerous.

Re: How I Gave Up Alternating Current

#89

Post by fnordfnordfnord »

wklauss wrote: post #30

I have long wanted to fully switch to DC in my life and would love to see common appliances designed for a DC world. It's a shame that the opportunity to discuss this is lost in this post because of the pedantic tone of the author. Phrases like "I think it was a bit presumptuous for the architect to assume I wanted a kitchen with my apartment and make me pay for it" or "I don’t want to live with red hot heating eleme…

>I have long wanted to fully switch to DC in my life and would love to see common appliances designed for a DC world.

Modern HE washers and dryers along with many other appliances already are in some sense. They have their own high efficiency power conversion built in to drive the motors at variable speeds. Powering current-gen stuff requires two redundant conversion steps, but the conversions don't lose too much.

Re: How I Gave Up Alternating Current

#90

Post by sbarron »

david-given wrote: post #63
justinph wrote: post #4

Interesting, but it seems like a lot of the lifestyle choices are just pushing the carbon/climate impact to someone else where the author doesn't have to think about it. Getting custom clothes made in china and shipped frequently is certainly far less environmentally friendly than simply re-using the clothes you already have. Taking an uber still burns gasoline. A bike would be better.

Hmm. A washing machine consumes about 100Wh == 360kJ for a load (ref: http://www.rpc.com.au/information/faq/power-consumption/wash... ). The Emma Mearsk, one of the largest container ships around, uses 13 tonnes of fuel an hour to transport 18000 containers, over a distance of (say) 20000 kilometres, which is 1kg of fuel to transport one container 45km (according to Wikipedia: https://en.wikipedia.org/wiki/Energy_eff…

The author can still do laundry and skip the washing machine. Hand wash, use the laundry water to flush the toilet, line dry.
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