Nuclear power and the environment.

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Haha, Agreed. "Clean, Green New Zealand" is a country of nuclearphobes (neologism) because of an association between nuclear weapons and nuclear powerplants. Everyone believes that if a nuclear plant was built in New Zealand the environment would be totally destroyed by meltdowns or something. Stupidly, nuclear power is the very "cleanest, greenest" source of energy we could have. We've got dozens of hydro dams, I think about 17 on the Waikato river alone. We have plenty of coal-fired stations, even a geothermal, but we're currently building wind farms because of a lack of energy. Nuclear power would solve New Zealand's and the world's energy problems. If only everyone would wake up

Sadly, no one applies the same standard to fossil fuels and guns. Just think of how many, both directly and indirectly, combustion has killed.

I pebble bed reactors have too many problems for me to consider them "safe." I think integral fast reactors are the way to go. (That is, unless we figure out sustainable fusion first.) IFR are about 100 more efficient than light water reactors because they burn the fuel more completely, which leaves less radioactive waste, and that with a much shorter half-life. They don't need enriched uranium, and could actually burn any actinide, including thorium, which is three times more abundant than uranium anyway. IFRs are passively safe and neither the fuel or waste can be used to make a nuclear weapon, because it has so many different isotopes mixed together that it would be ever harder to extract purified plutonium or enriched uranium from that than from natural ore.

The only significant safety issue is the liquid sodium coolant. Pure sodium is highly reactive, and could start a fire if there was a leak, but the whole point of using a metal coolant is so it doesn't have to be pressurized. Since we can reliably make pressurized water reactors, the plumbing on an IFR should be relatively easy to build.

I think the only reason that IFRs haven't taken off is that it's currently cheaper to bury "spent" fuel than to build a better reactor and pyroprocess the fuel to burn it completely. That's a very short-term view, however. If laws were changed so that the power companies had to pay for all the damage fossil fuel pollution causes, and pay to maintain storage for their "spent" fuel, and if permits to build a nuclear plant weren't so easy to revoke, I think we would be using a lot of IFRs.

So far, I have not been able to find any downside to pebble bed safety.

What are you talking about Encyclopedia?


The dangerous fission by products cited early, amount to about a cubic meter per year,
and they can easily be recycled. Compare that to the tons of lead, sulfer and other toxic materials
that are released directly into the environment by a coal fired plant.

There is no contest between the two.

clean safe coal?

Coal is dirty and oftein tainted with radium, the fly ash from some coal burning plants is very radioactive.

Rather than a sodium cooled fast reactor why not use a liquid lead cooled reactor, or use a BWR or CANDU. I think that the BWR and CANDU are better than a PWR in some ways. The BWR can be thought of as being a PWR which has been designed to operated perfectly under fault conditions (major leak in a steam boiler between the primary and secondary circuits) so the BWR is very robust against pipe bursts.

I think the pebble bed reactor is better than most designs but I am not sure how well the fuel can be reprocessed after use.

As a purely practical matter, nuclear is not really going anywhere or solving anyone's problems, at least in the US. It's clear that between NIMBY's, terrorist threat (or public perception thereof), and total lack of clear directed government policy dictating how to handle/recycle/dispose of nuclear waste, that technological reasons are the least of nuclear power's inhibitors.

Instead, we have other renewable energy that can be put in much more effectively. Between land wind farms in the great plains (the so-called "middle east of wind"), and offshore wind capacity on both coasts, there's more than enough potential power sources to provide the US with double its current electric usage plus export to Canada. Add on the advanced in thin-film solar and already existing hydro to buoy the grid when the wind doesn't blow and it's entirely feasible to completely displace coal as a electric source without building another watt of nuclear capability.

The major issue is actually not power generation, but transmission. The US electric grid is quite outdated in terms of being able to transmit power to where it's needed. Moreso than anything else, so-called "smart grid" technologies are what's needed.

And on electric cars: the problem is almost entirely with battery technology. Every other component of electric vehicles is mature cost-effective technology - electric motors are startlingly efficient, and the savings in not only energy/fuel costs but maintenance as well (electric motors require far less attention then combustion engines) would be so tremendous that it would more then offset the additional stress on the electric grid.

But alas, there's simply not any good enough battery technology. Perhaps lithium battery technology will become cost-effective at some point in the future, but as of right now, there is not anywhere near enough production capacity to build lithium batteries for production electric cars - and lithium is the best tech we have.

I would reply by saying that as long as the plutonium, neptunium and postplutonium actinides are removed from used fuel and reused as fuel then the waste problem shrinks in terms of how long should the waste be isolated from man and his environment. I think that advanced reprocessing is the way forward. Already by the US and the EU have worked out much of the science associated with the proposed new processes. But many of the fine details need to be addressed now.



No, the generation of electric power by solar cells is not perfect, if you consider the whole life cycle of the solar cell you will see that on green hosue emissions alone that while nulear and solar cells are far better than coal (Data from the UN). Nuclear is better than solar cells.

http://www.iaea.org/Publications/Magazi ... ticle4.pdf



I can not comment on the losses of energy in the US power grids but I know that stability and outage are major issues in large power grids. The US have had some power cuts in recent years because of problems with some power grids, these were due to things such as major power lines failing or grid transformers which malfunctioned.

I think that AC to DC to AC links could improve the grid by allowing it to be broken down into slightly smaller grids. The thing is that the DC to AC converter provides a robust way to transfer energy from one grid to another without the need for both to by runnign at exactly the same frequency and phase.

But that's not my point. I was arguing that, irrespective of our technological ability to overcome problems with nuclear power, nontechnical issues dominate. Regardless of how advanced our reprocessing technology is, the public attitudes and the government policies are so far behind that I fail to see how anything but a monumental shift in the outlook will make nuclear power very viable in the immediate future.



Indeed, there are examples of high voltage DC transmission lines in the US that work well, typically carrying hydro power. HVDC technology has improved a lot recently, as well. Yet at the same time we can't go and rebuild all of our transmission lines or even just blindly build new ones - we have to figure out how to use the current infrastructure more efficiently.

This is moreso an issue in the US because of the greater distances involved, but is also becoming an issue in europe as they grow more reliant on offshore wind in the north sea as well as aging infrastructure in eastern europe.

I think that the waste issue is so bad becuase of the long time which high level waste or used fuel needs to be isolated from the environment. The length of time is about 1 million years, if we bring that down to only 300 to 400 years then I think that the public relations problem will shrink greatly.

I can think of plenty of ways of isolating nasties from man and his environment if the required isolation time is only 400 years. I wish that more irksome things could be isolated with the same ease.

PHEVs have a roughly 5c/mile operating cost advantage compared to the exact same conventional vehicle, mostly through maintenance savings and also gas prices compared to battery/electricity prices, although that depends greatly on driving habits. Over a ~250k miles lifetime would reach cost parity even w/ gas at $1.50/gallon and a ~$10k price premium. Naturally if oil goes back up to $100+/bbl, the owner would save ~$5-10k over the life of the vehicle.

The problem is that people don't really care about paying less overall. They tend to want to pay less upfront. For instance during the course of a 30 year loan an owner would pay twice what they would've if they had just bought the house outright. So, since PHEVs represent a larger upfront cost, even if they may save money in the long run, or at the very least cost the same and provide insulation against higher fuel prices, people still won't go for 'em.

In terms of batteries, we can get Lithium Iron Phosphate stuff from China for ~$550-600/kWh shipped to the port of LA, and manufacturers can get that same stuff for ~$350/kWh in bulk. For an individual this means that if they were to hybridize their own vehicle, lets say a small sedan, and use the battery down to 40% of capacity, battery storage costs would be ~13c/kWh, or ~2.7c/mile. The manufacturer would be able to get it for ~1.6c/mile. Electricity costs at the U.S. average would add another 2.8c/mile. W/ gas at $1.50/gallon and an identical car at 28mpg combined, fuel costs are ~5.3c/mile, so even w/ $1.50/gallon gas there's still a ~1c/mile advantage in fuel costs for a electric vehicle during the combined cycle (city and highway). Now, if we are judicious, and only use EV mode for low speed driving/traffic while using gas for high speed driving, we end up using batteries/electricity where the economically compete well w/ gasoline, and even a DIY'er would likely save money.

Anyway, it isn't that batteries aren't ready so much as people don't care much about spending less overall on transportation if it means they have to spend more up front with a recession and oil prices in the gutter compared to the last few years.

Even if people wanted to buy electric, the issue isn't so much the direct cost of lithium batteries - the cost of lithium batteries would likely skyrocket if everyone started buying them, for the simple reason that there isn't solid top-to-bottom production capacity for lithium. Current production capability barely supplies people's demand for lithium batteries for consumer electronics.

That is, not only is there not enough lithium battery factories for electric cars, there's not anywhere close enough lithium mining operation in the whole world to feed those factories in the first place. That may change in the next 5-10 years if there's a concerted effort to build the infrastructure, but for now, lithium is not "there" as a high-capacity EV power supply.

I doubt manufacturers would bother w/ PHEVs if the battery price made it prohibitively expensive. What we would do if oil prices made it attractive, and we didn't have domestic manufacturers insisting that the best time to sell SUVs was when oil was $145/bbl, would be to work out contracts w/ whatever manufacturer and make however many PH/EVs. Businesses are a bit more flexible than consumers wrt production runs. If demand for batteries is really that high then some businesses simply won't use 'em, and the price will stay sufficiently low to make however many. Eventually capacity will expand and we can make more if demand for the vehicles stays high.

Edited for errors, figures below.

In fact, programs like CARB's ZEV mandate would be great since they could cut demand by enough to temper price swings. For instance the drop from $145/bbl to $40/bbl only came after a .1% drop in demand. Having .3% of the world's vehicles as PHEVs would serve to provide something of a buffer for oil price swings that result in hundreds of billions, if not trillions, in extra costs, not counting the externalized costs. This could undoubtedly be met w/ current Lithium Carbonate production and probably met w/ current lithium battery production capacity. Battery production capacity can scale up as oil plateaus/declines. Lithium isn't "there" because there's no demand for it. When there is, it'll "show up".

Last edited by yesplease on 03 Jan 2009, 6:04 am, edited 1 time in total.

I don't know where you get your numbers, but they don't make any sense.

For one thing the USGS claims that 2007 international lithium production measured around 25000 metric tons (USGS) which is around 55 million lbs. Note that this is by mass of lithium content, not lithium carbonate (the carbonate ion weigh about 6 times more than the lithium ion), so guesstimate 400 million lbs of lithium carbonate production.

But then we have to figure how much lithium carbonate we need per battery. I don't really like Forbes as a source, but they claim that Argonne National Labs estimates about 3.1 lbs/kWh (forbes) Assume this is high, so let's take 1 lb/kWh as a lower bound.

The GM Volt has 16 kWh of battery, so let's take 10 kWh for a supposed super-efficient PHEV (again lower bound), or 10 lbs of lithium carbonate per car - or about 40 million cars, using the entire world production of lithium.

Some people out there are claiming that this means that lithium-ion batteries will never work in electric cars - I'm certainly not claiming that. But I am saying, there is a lot of work to do, top-to-bottom, before lithium ion is a viable EV power source, unfortunately.

Doh! Good catch!
Lithium Cobalt and Lithium Manganese require about that much per kWh, but Lithium Iron Phosphate, what's scheduled to get dropped in the Volt if it ever gets made, and pretty much the front runner for EVs (due to the lowest cost per kWh stored) only requires about an eighth of the Lithium the other two, which make up most battery production these days, do. So figure ~300+ million Volt sized HEVs/year.
The viability really depends on what the cost/range/performance requirements are. In terms of operating costs they do much better than conventional cars in countries like France and the U.K. due to the higher fuel taxes, and even in the states w/ lower fuel taxes they are competitive w/ conventional cars in dense urban environments. Like everything else it depends. I wouldn't go so far as to say they are viable in all applications, but given how far cost has come compared to storage life they are certainly viable in some.