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Giving Up Alternating Current
An anonymous reader writes: Yesterday we discussed Soylent, the artificial food substitute created by Rob Rhinehart and his team. As it turns out, this isn't Rhinehart's only unusual sustainability project. In a new post, he explains how he gave up on alternating current — a tough proposition for anyone living in the U.S. and still interested in using all sorts of modern technology. Rhinehart says, "Most power in the US is generated by burning coal, immediately squandering 67% of its energy, then run through a steam turbine, losing another 50%, then sent across transmission lines, losing another 5%, then to charge a DC device like a cell phone another 50% is lost in conversion. This means for 100 watts of coal or oil burned my phone gets a mere 16."
The biggest hindrance was the kitchen. As you might expect for the creator of Soylent, he doesn't cook, and was able to get rid of almost all kitchen appliances because of that. He uses a butane stove for hot beverages. He powers a small computer off batteries, which get their energy from solar panels. For intensive tasks, he remotes to more powerful machines. He re-wired his apartment's LED lighting to run off direct current. Have any of you made similar changes? How much of an effect does this really have?
The biggest hindrance was the kitchen. As you might expect for the creator of Soylent, he doesn't cook, and was able to get rid of almost all kitchen appliances because of that. He uses a butane stove for hot beverages. He powers a small computer off batteries, which get their energy from solar panels. For intensive tasks, he remotes to more powerful machines. He re-wired his apartment's LED lighting to run off direct current. Have any of you made similar changes? How much of an effect does this really have?
He's still living on the electrical grid, he's just not using it at home.
Also, WTF? "I enjoy doing laundry about as much as doing dishes. I get my clothing custom made in China for prices you would not believe and have new ones regularly shipped to me."
So he gave up refrigeration?
an ac synchronous motor is much more efficient than DC alternatives.
Why doesn’t he just use a gas stove?
At that point why heat drinks at all? It’s wastefull.
His low power computer? He’s just using AC remotely.
Why not just move to a mud hut in east Africa?
He has decided upon a very specific, and limiting, style of living. Bravo. Now try applying his philosophy to a household with children. Or a household frequented by guests. Try this in less sunny locales.
I think it is admirable to try to be different, and to advocate alternative. I am completely turned off by his holier than thou attitude and his dismissiveness towards that which does not fit his chosen lifestyle.
Due to the very poor selection of DC appliances and often their RV bloated price tags, I have opted to keep AC, but generate it locally. Instead of buying a DC to DC supply for a laptop to get 19V for about $100, I bought a 1KW inverter instead for about the same price. If I don't want all my lights to be Fluorescent Cool White in color, I can use the 9W 3K bulbs instead in a warm white with high Color Rendering Index >94%. Try it. Try to find 12V RV bulbs that are not Amber, Red, or Cool White 6K. Most of the outlets in my RV are running off the inverter. Only the kitchen and bath loop are still on traditional shore power or generator along with the AC. This limits the generator runtime where shore power is not handy.
I have not trimmed my home use enough yet to cut loose from the grid. Heat pumps and long wet winters on solar just is not a match yet. They haven't fixed the solar when the sun doesn't shine problem yet.
I don't have to mess around with trying to adapt everything to 12 or 24V. With a good size deep cycle battery, even normal microwave oven, blow dryer, other short duration high amperage loads are possible that is simply not an option on DC.
The truth shall set you free!
If you had to remote to another machine for every intensive task, do you think you'd maintain the same volume of intensive tasks?
In summary, he reduced a bunch of things to zero, and another heap got reduced greatly, and then some smart aleck comes along and says he did nothing because this thing over here didn't get reduced much. Someone's missing the point.
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Getting rid of AC for off grid applications makes sense. I'm all for it and look forward to the new DC appliances we're seeing come on market.
however, this article is not going to have people following suit.
I'm not giving up my quality of life. I don't have to and I don't want to and its the 21st century so anyone that disagrees can eat a rail gun round to the face.
I do believe in sustainable living. However, more in the way of breaking free from crumbling infrustructure and gaining a certain amount of logistical indepedence.
I'm a big believer in the backyard green house. I think solar panels and wind mills are a good idea AT YOUR HOUSE. And I am looking forward to economical energy storage systems that work at a personal level.
Am I dumping my refrigerator and cooking food on a camping stove? No.
Really none of this sustainable stuff works in an urban environment. Its sort of odd that so many people that like the idea live in the one place where it isn't possible. Logistically you're going to be depending on a very energy and resource intensive infrastructure and there's just no way around that in a city. That "IS" the city. The city is all the things the sustainable people say they don't like. Live in the suburbs and you have a CHOICE. You have enough property that you can do something. Live rural and you can go completely off grid for everything... food, water, power, whatever... live like the Amish or something. Yabba dabba doo. But in a city you're on the grid. I don't care if you shut off the breakers in your apartment or drink your own pee. You're on the grid because everyone around you is on the grid and you depend on them whether you're drinking your own pee or not.
Here is my suggestion for the urbanites. Support nuclear power. Worship the fucking atom.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
HVAC uses 3-phase AC power which is actually pretty efficient for motors, especially if you want motors that are going to last a long time. Pretty much all brushless motors are driven by AC (even computer fans have a controller inside to generate AC). 3-phase is great for motors that run at a single RPM, such as what is used in compressors and pumps for HVAC.
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The problem with Rob's assessment is that his efficiency numbers, expect for power transmission, are way off the mark. It is MUCH better than he purports! DC to AC conversion is roughly 90% or more efficient these days so you are not saving much by using DC at home rather than AC. It is simply not worth it to limit yourself so much by having only DC appliances.
AC by virtue of alternating, passes though zero current flow and zero voltage 120 times a second in this country. When you have an arc, you are passing an electric current though a plasma and that requires that you keep it hot and ionized. It is the current that keeps the plasma hot and ionized.
As a switch contact opens, initially the distance between the contacts is under the flash over voltage and an arc of plasma is formed. This arc requires current to keep flowing though it to be maintained and as the contacts separate further the resistance of the plasma path increases, lowering the current. Eventually in AC circuits, the voltage needed to maintain the plasma path starts to cycle under this minimum value for longer and longer times and current starts to fall off on average. This falling current, makes the arc plasma start to fade and will eventually extinguish the arc during the times when the current and voltage cross the zero level.
DC has no regular fall off in the plasma because it is always there, full on, full current. This means that switching similar voltages and currents in DC requires additional distance over AC. DC starts the arc and builds the plasma without stopping and only the resistance of the plasma as the distance increases is what will cause the current to get lower and lower until the arc extinguishes. There are no "off" times like there is in AC so the arc exists over a larger distance.
ALSO, on very high voltage AC circuits, it is possible to disconnect the circuit during a zero crossing. In that case, assuming you can get the contacts far enough apart to avoid flashing over, there never will be an arc to start with. Even though it's mechanically difficult to move things that fast, they sometimes do this kind of thing to suppress the arc in AC. This doesn't work in DC because there is never a zero crossing.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
I lived in a house that was totally off grid. It actually was never on grid, because the owners already had a wind turbine back in the day when the utility companies where doing the rural electrification project, and declined to be added to the grid. This house had coal heat, gas and wood stoves, gas refrigeration, and no AC at all. Located in central Montana, it was equipped with a bank of around 12 CAT bulldozer batteries, (which replaced about twenty 1 gallon square glass jars with lead plates) over 200 square feet of solar panels, a small wind turbine (about a 2 foot blade) and a backup propane generator, that was set up to automatically start up and top up the system if it dropped below a certain charge level. So basically, all the system had for load was incandessent bulbs, and occasionally a television. In the winter, that generator ran intermittently during the day, and after dark, it ran until you went to bed, and shut all the lights off. Obviously, using LED's and more power efficient TV's is possible now, but it takes a hell of a setup to go all off grid. (you could not run a modern computer or a microwave on that system, the computers where to sensitive to the square sin of the inverters, and would randomly restart. Microwaves would pop breakers if not plugged in directly to the generator.)
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.