Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror

Comment Re:Renewable Energy vs Waste of Energy (Score 1) 626

I agree.

At present we dig up vast amounts of thorium as waste from regular mines, especially when digging up rare earths.

Uranium is in very short supply, and 99% of it in nature is useless for power generation, and when that 1% is used for power, we only extract about 0.5% of the power in it.
Thorium on the other hand is about 10 times more abundant then uranium, and 100% of it is usable for power, and nearly 100% of the thorium used will be converted.

Comment Re:Sign on some airport (Score 1) 626

0.3% of sahara is still 28.2 billion m2
Add construction, infrastructure, maintenance and storage for about 2/3 of the energy produced, and cost becomes prohibitively expensive.
I'm not saying that we shouldn't do part of it, but it is infeasible to do it all. I'm not even sure there is enough copper left in the world to pull it off.

Comment Re:Sign on some airport (Score 1) 626

2% of Sahara's surface is still a MASSIVE area. And the production works best in the day time. Then there is that little problem of Sahara being a very unfriendly place for something like this. Constant wind and sand getting everywhere you don't want it, on the receptor surfaces and in the mechanics.

Sahara is about 9,400,000 km2, 2% of that is still 188,000 km2 or 188 billion m2

Comment Short answer? No, they are always forgetting cars (Score 1) 626

When ever I hear talk about renewable energy, they are always talking about peak capacity, they forget that at best a Wind Turbine only produced about 50% of its rated power on average. Too little wind, or too much, and they produce nothing.

But there is always one thing they forget, and IIRC that is the main energy consumer of them all: Cars. Or rather ALL transport that aren't done by rails. True, there are electric cars, but:
1. Limited range
2. They take a lot of time to recharge, though some are trying to get around that, the problem being that of building up the infrastructure before the systems can be put to use. This is nearly prohibitively expensive.
3. Batteries.

Power

Submission + - White House petition for an initiative to transform nuclear power to Thorium (whitehouse.gov)

JavaBear writes: Thorium is gaining interest, with research happening around the world, but it pales compared to the research and funding going into conventional nuclear power, and into updating outdated power stations. The interest is just not shared by the US government, as there are too much money at stake continuing the current dead end. The main problem is that of regulation, the US could be self sufficient in rare earths, and even export it, if not for regulation designating thorium found with these as nuclear waste. A small rare earth mine would get about 5000 tons of thorium a year as a byproduct, enough to generate power equal to the estimates total annual power consumption of the planet.
From the petition:
"Of the 104 nuclear reactors currently active in the US, 69 are pressurized water reactors and 35 are boiling water reactors. Both of these designs for nuclear reactors are sixty years old and as such are outdated, not to mention past their projected lifetime of 40 years. The Fukushima plant in Japan used boiling water reactors and the ensuing tragedy was a wake-up call for nuclear power."

Comment Re:US Metric System (Score 1) 1387

"So, how many cubic meters in a liter (in your head, please, and quickly)? How many grams of water in a cubic meter of water? And why aren't either of these 1? Using arbitrary orders-of-magnitude for more-or-less fundamental measures sure doesn't make the system simpler..."

In my head, 1 m^3 = 1000l, so 1l is 0.001m^3
1 m^3 of water is 1000kg = 1,000,000g

Comment Re:US Metric System (Score 1) 1387

Materials have different densities. Water happens to be an easy one to get, and it is incompressible (great for volume calculations).
So SI volume and weight is based on (pure) water, at 20 degrees centigrade. 0 degrees C is the freezing point of water at 1000hPa), and 100 degrees C is the boiling point.

Why they didn't normalize standard atmospheric pressure to 1000hPa I have no idea. it is about 1013hPa if I recall.

Slashdot Top Deals

"Card readers? We don't need no stinking card readers." -- Peter da Silva (at the National Academy of Sciencies, 1965, in a particularly vivid fantasy)

Working...