A question of scale: Electricity and steel making.

[hunter]

How many photovoltaic panels would it take to fire up one of these?



This is an electric arc furnace.

60-70% of the steel used in the United States is made from scrap recycled in furnaces like these. It requires about 475 kilowatt hours to make a ton of steel. The United States uses about 130 million tons of steel a year.

It takes a tremendous economic infrastructure to support furnaces like these, and the cost of steel produced is directly related to the cost of electricity.

This is not a process that can be carried out on "small is beautiful" scales using expensive sources of electricity.

We have a couple of choices to make. We can continue doing what we are doing now, using coal to power these sectors of our economy, in which case climate changes and pollution might kill billions of people...

-or-

We can downscale such industries so that they might be supported by nuclear energy.

-or-

We can radically transform our economy into something few of us here would recognize -- I always imagine something like Ursula K. Le Guin's Always Coming Home

-or-

maybe, if we really are just too stupid to survive, the usual fallback position of Nature: Destruction, Death, and Extinction.

[donco6]

1. Why can't we just diversify our power sources?

All power generated just feeds into the grid anyway. It's not like power from THIS coal plant feeds the arc welder, while THIS wind turbine feeds my house.

[formercia]

2. Smaller vehicles use less steel. n/t

[jpak]

3. What do you want to use the steel for....SUV's...aircraft carriers???

50 years from now, there will be no oil and no auto industry...and the demand for steel will be severely curtailed.

Geothermal and hydroelectricity (supported by large-scale wind and PV-farms) can be used to produce electricity for steel or aluminum production (for whatever we will be using it for...).

[Dead_Parrot]

4. You're kidding, aren't you?

What about buildings, bridges, busses & trains (you'll need lots of them), household appliances, wind turbines (of course), boats, farm machinery, a lot of canned food, just about any sort of fixed machinery... It's like the list of "things we use oil for". Whilst not making a shitload of SUVs will help, you'll only be saving a few percent.

Switching to aluminum doesn't help much, either.

[jpak]

7. We won't be building any Sears Towers or WTC's or Escalades

or similar Supersized unsustainable structures or machines

I didn't say we would not "do without" - only that we will do different, smarter and with a reduced need for steel.

BTW, steel production accounts for ~2.5% of US energy consumption and 8% of energy use in the US manufacturing sector.

The auto industry dominates US steel consumption ~15-20% of total US consumption.

Railroad rolling stock and rails use ~1.2% of total US steel consumption.

and appliance manufacture ~1.3%

and building materials ~1.6%

and cans and barrels ~3.8%

So we could do a lot with less...

[Dead_Parrot]

11. You could do without 15-20%, sure...

But the US public transport is in a shambles. you need to be putting masive amounts into the rail infrastucture, not sitting around boasting that it only uses 1.2% of your steel. And even if you ignore that, you still got the other 80% to power, somehow.

[depakid]

15. "US public transport is in a shambles"

Hell, in many places it barely even exists!

[Ready4Change]

10. That's why we need to diversify ASAP, imo.

There are some things for which we need power in a far more concentrated form that we can easily get from solar or wind. Like steel mills, these things are ideal clients for big coal or nuclear power generation plants.

However, many other things, such as residential or non-industrial power, can be handled nicely by distributed energy generation, like solar, wind or micro hydro. By powering those with alternatives, we can preserve the non-renewable fuels for areas they are ideal, at least for as long as possible.

Perhaps, but doing that, we can buy the time to develop more robust renewables. If we can't, then the lifespan of our form of civilization is limited.

[Dead_Parrot]

13. I'd agree we need to get out of our current portfolio

Nuclear can supply shitloads of power, and we know how to do it right, but it should only be a stop-gap for something else: whether that's fussion, or decent energy storage, or - as you put it - "robust" renewables, only time will tell.

What we can't do is meet current energy demands from current renewables technology...

[hunter]

6. A couple of things come to mind...

High speed rail, public transport, and construction materials for urban and suburban infill projects.

Poorly built and energy inefficient low density suburban housing will be replaced by something more substantial.

Nobody's going to want to live in places they can't afford to heat, cool, or commute to work from.

After we lose a few more cities (New Orleans was just the first) I think the general public will start to believe shutting down the coal industry is a good idea.

Maybe this sort of economic restructuring could be done without nukes, maybe not. I don't think that experiment will be carried out in the United States. We'll sit around squabbling 'til we hurt bad enough, and then we'll copy some nation that has actually made it work.

[phantom power]

5. Somebody is working on "foamed steel"

I don't know how much that saves, or if anybody has industrialized it yet. But supposedly it's as strong as regular steel at a fraction of the total mass.

[skids]

8. Photovoltaic Panels? Use mirrors.

They cost a whole lot less. Most of the research, however, is being done on Aluminum, not steel, as working with it is a notoriously energy intensive application:

http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000123000002000117000001&idtype=cvips&gifs=yes
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000123000002000125000001&idtype=cvips&gifs=yes

http://www.secat.net/docs/resources/advancedmeltingtechnologies.pdf

[hunter]

9. That's a lot of mirrors.

I was in Daggett when they fired this 10 Megawatt baby up:

[Dead_Parrot]

12. Now that's a nice idea...

...I hope they can make it work.

[NNadir]

14. If they do make it work, it will work about 30% of the time.

The economics of plants of all types, including steel plants, is determined by the percentage of time they can operate. You have to have three times as many plants to produce the same amount of steel, and three times the land, three times the construction cost, three times the amount of materials hauled across the desert (presumably that's where it will be) and you have put in three times as much pipe to bring water in.

I'll bet the economics of such a system will always be lousy.

It doesn't matter. We can sacrifice anyone who can't afford a tripling of steel prices on the altar of the sun god. We have a great religion going.

[hunter]

16. At the very least it would be a tripling of steel prices.

Oh well, when civilization collapses and billions of people die, it will be easy to find an old car spring to make a sword from if you are hungry and need to kill off a few of your neighbors.

From a sword-making page:

"The leaf spring in most cars is hard enough and tough enough to eat every commercially available sword that I could find in almost 30 years of destructive testing."

Our miserable descendants won't have to start from scratch.

[NNadir]

17. This is great news.

It's good to have spring based swords if you u are in a war for the last mirror fueled steel retort.

I'll be sure to share your insight with my children, in case they don't starve to death first.