Thursday, March 03, 2005

Making up our minds

Electricity generator Meridian Energy wants New Zealanders to make up our minds about what sorts of generation options we will support. But looking over which projects have succeeded or failed over the past few years, it's clear that we already have. We don't like big canal-based hydro projects that ruin a river by diverting its flow through generators (rather than ruining only a portion of it by creating a lake), and we do not like coal. Gas power plants seem to be acceptable, due to their general lack of pollution, and there's been little public complaint about geothermal. But what's really striking is the public support for wind. While some consents have been denied (notably for Genesis' plans to build a small farm at Awhitu), generally the public is quite supportive of wind farms, to the extent that some public consultations have had 90% of their submissions in favour, and residents near other power developments are saying "don't build X, build a wind farm instead". And now that New Zealand's major environmental groups have got on board and are actively promoting wind power, this trend is only going to get stronger.


Think of the birds!

Posted by Anonymous : 3/04/2005 12:39:00 AM

Think of the fish, think of the people, think of the corporations,think of the world....maybe it comes down to what is the lesser evil ethically speaking?

Posted by Anonymous : 3/04/2005 01:33:00 AM

There are worries about birds being killed, and DOC is looking into it with a study at the new Te Rere Hau site in Palmerston North. There the windfarm is being built close to a native bird habitat, so they're wanting detailed records of finds of dead birds (and ideally, cause of death) over I think the first five years of operation. Which should hopefuly provide some answers as to the ecological costs of windfarms...

Posted by Idiot/Savant : 3/04/2005 09:46:00 AM

Lets ban cats! And go nuclear!

Posted by Anonymous : 3/04/2005 11:42:00 AM

Gas power plants are indeed cheap, flexible, small and produce little noxious exhaust and relatively little CO2.

They do however eat up a declining resource that (along with oil) is currently essential as a transport fuel and chemical feedstock. Thus we should be very careful about installing more gas-fueled generation.

Posted by Rich : 3/04/2005 12:00:00 PM

Rich: and in particular, New Zealand is looking down the barrel of a gas shortage in just a few years. And while we can avoid it by finding large new deposits or becoming dependent on external supplies, neither is really a long-term solution. But they will last long enough for fusion (or some other alternative) to become credible (you can stop laughing now).

Generators know this, which is why they've suddenly become interested in wind.

Posted by Idiot/Savant : 3/04/2005 12:36:00 PM

the obvious question is how much power can wind power produce. It seems it is probably like having a bycycle in your house hooked up to a battery - sure it is environmentally friendly but it jsut wont give oyu enough power.
Now that doesnt mean oyu dont have wind power it jsut means the question as to what ELSE you will use remains.
Also you cant say "im going to replace all the pylons with windmills" (ok well some idiots would say it but hey) - because even windmills need somthing to transfer power from windy places to high consumption areas. anyway - no one is going to buy a million dollar property in auckland and put a windmill on it.

I sugest hydro power, nuclear power and wind power.

Posted by Genius : 3/04/2005 11:28:00 PM

Genius: long-term estimates of New Zealand's wind-resource are on the order of 100,000 GWh per annum - about three times our total current electricity usage. Medium-term estimates are that it could provide 20% of electricity consumption within 15 years. By way of comparison, in a good year, we generate around 70% of our electricity from hydro.

(Details and links to studies here)

You cannot replace everything with wind turbines, of course, but combined with hydro, geothermal, and a bit of gas where necessary, it would give us a relatively clean mix - and cheaply too.

And it goes without saying that you need an efficient national grid to move the power around. But you'll notice that its NIMBY's, not Greens, who are objecting to that.

Posted by Idiot/Savant : 3/05/2005 12:15:00 AM

There's also large steps to be had in terms of energy efficiency. Heating and cooling of buildings could be handled through regulated design requirements to reduce electricity demand; solar underfloor radiant heating for example (any building can be designed to self-cool).
Solar water heating has come a long way in terms of reliability, that's 1/3 of household consumption right there, you recover about 7%PA on investment IIRC (more as electricity prices rise).

Heavy industry will still need alot of electricity, but regulated pricing structures would encourage any new factories closer to the source, which would reduce generation requirements by ~5% all by itself.

Definately stay away from nuclear. 10,000 years of waste management is really quite expensive.

Posted by Anonymous : 3/05/2005 12:42:00 AM

but how much waste? jsut put it all in one spot you dont plan on using for anything in particular for the next 10,000 years. Ridiculously less waste proble than coal etc.

Posted by Genius : 3/05/2005 07:31:00 PM

Genius; you're kidding right?

Have a look at how the real world deals with its nuclear waste.
Dump it off Somalia, they don't have a government to complain: pitty about the tidal wave.
Turn it into bombs and tank shells and fire it into Iraq, Somalia, Serbia, Chechnya, or wherever.
Leave it sitting in a cooling pond near the reactor, and hope for the best.
Ship it to Japan and turn it into a worse type of nuclear waste, and don't ask what they do with that.

The reason they do that with the stuff is that dealing with it properly makes it uneconomic; like gold mines and thier Arsenic dumps.

Posted by Anonymous : 3/06/2005 02:24:00 AM

the uranium all comes from a spot in the ground - the waste is just slightly less of hte same sort of thing.
just put it in the same place somwhere nad dont worry about it.
You could empty a uranium mine and then fill it back up again.

Posted by Genius : 3/06/2005 09:58:00 AM

tussock and genius - go learn some basic phyics before commenting...

How the nuclear fuel cycle works:
- ore is dug out of the ground - it's relatively low risk, largely due to dilution.

- the ore is purified (in the same way as for any metal) and enriched (by a variety of methods). The latter process increases the concentration of the fissile isotope U235 - for most nuclear power processed, only a small amount of enrichment is carried out - nuclear bombs and certain reactor designs, such as those used in submarines, use a higher degree of enrichment.

- U235 is neither more radioactive or more toxic than U238 - its key characteristic is that it undergoes nuclear fission, releasing substantial energy. This process is used in both nuclear reactors and atomic bombs.

- Depleted uranium is almost pure U238, produced in the enrichment process by removing the fissile U235. It is used in various applications (armour, projectiles and weights) because of its high density. There is some controversy over the toxicity of DU - it is however much the same substance as natural uranium.

- Nuclear fission in a reactor produces plutonium and a number of reaction products with various half lives. Many of these are highly radioactive and produce heat. Plutonium is both toxic, radioactive (though less so than other fission products) and a fissile material (and hence a proliferation risk).

- The options for dealing with fission products from nuclear power amount to containment and reprocessing. In the latter case, plutonium is separated and used as reactor fuel or to make atomic bombs. Either process results in a substantial amount of fission product requiring storage for an extended length of time. The radioactive and heat emitting nature of fission products make this storage difficult.

Posted by Rich : 3/07/2005 10:40:00 AM

Rich: and all of this requires a substantial industry to reprocess and store the fuel, or else shipping it to somewhere that does (creating some environmental and proliferation risk). Not to mention somewhere safe to put what's left at the end. And in a country as tectonically active as new Zealand, the latter in particular poses a serious problem.

In 1978, the Royal Commission on Nuclear Power Generation concluded that nuclear power in NZ was simply not feasible, partly due to this problem. And like Mike, I don't think anything has really changed.

Posted by Idiot/Savant : 3/07/2005 11:09:00 AM

> ore is dug out of the ground - it's relatively low risk, largely due to dilution.

In case you don't know it is pretty easy to dilute stuff.
Whatever your argument is the results of the nuclear reaction are going to have less energy than the initial resources if some part has more energy I suggest it goes back in the reactor to make more heat.

> Either process results in a substantial amount of fission product requiring storage for an extended length of time.

stick them in a hole in the ground for example one of the holes in the ground the uranium came from in the first place. if it wasn't hurting anyone there then the waste shouldnt hurt anyone either.

the big problems seem to be
1) "not in my back yard"
2) "ewww nuclear ewwww"

Posted by Genius : 3/07/2005 11:54:00 AM

It can't be that hard to understand:

- all matter has a *huge* energy equivalent (e=mc2) - under normal conditions with stable elements this remains latent and is not a problem to anyone.

- In its natural state, uranium decays very slowly, releasing very little energy (as alpha radiation) and turning into lead.

- In a reactor, uranium is placed in a configuration that allows it to undergo nuclear fission (a different process to normal radioative decay). This results in it transmuting into various elements "fission products"

- These "fission products" are much more unstable than Uranium and decay rapidly producing radioactivity and hence heat. Consequently, they are extremely hazardous materials.

- I'd be happy to walk around with 1/2 a kilo of natural uranium - if I did this with the resulting fission products, I'd be dead in hours.

Do you understand? or are you taking a faith based approach and ignoring simple physics!

Posted by Rich : 3/07/2005 02:34:00 PM

now you have changed your argument from the dilution one...
anyway how many tonnes of radioactive waste do all the nuclear plants in the world produce?
I recon you could fit it all in all in a not so big hole.

Posted by Genius : 3/07/2005 05:31:00 PM

To see what happens when you throw nuclear waste in a hole, see here or here

Posted by Rich : 3/07/2005 08:07:00 PM

1977? Come on... they had barely developed the wheel back then let alone mastered waste disposal.

Posted by Genius : 3/07/2005 11:21:00 PM

Genius: Rich isn't making any argument based on dilution. He's pointing out that what we get out of a reactor is rather hotter (in both senses of the word) than what goes in. FFS, fission isn't that hard to understand...

I've played with a fuel rod from the subcritical reactor they used to have in the engineering school down at Canterbury; they passed it round during a lecture, and it was perfectly safe (well, as safe as the Port Hills, or a trip in a plane, which are risks I happily bear). But I wouldn't want to go near the stuff once it had been used; high-intensity gamma rays are bad for you.

As Rich's examples showed, you cannot just throw the resulting waste in a hole in the ground without causing problems (and if you disagree, go and look up what "criticality" means - the fact they have to worry about this at dump sites should scare the living shit out of you). Instead, you need a very safe, stable, and well-guarded hole, where the waste will not be stolen by terrorists or leach into the water table or the local environment. And you need that hole to stay safe, stable and well-guarded for thousands of years. This is not something NZ can do given our geology, and even the US has trouble with it: they've built their facility in a dormant - not extinct - volcano, with easy access to the water table...

Posted by Idiot/Savant : 3/08/2005 01:25:00 AM

Genius: oh, and in answer to your question: worldwide, the nuclear industry generates around 12,000 T of spent fuel a year. But when a reactor is decommissioned, they also have to treat large chunks of it as waste, due to induced radioactivity. Given the requirements for shielding and avoiding criticality, you need a pretty big hole...

Posted by Idiot/Savant : 3/08/2005 01:27:00 AM

> This is not something NZ can do

obviously we (the world) should put it all in one place. write off a few square kilometers in some desert somwhere. 12000 tonnes should be somthing less than 10 meters by 30 by 30 meters. so we need a hole 30 meters by 30 meters and 10 deep per year. To allow for the waste the world will produce over the forseable future you might want to make it the size of a normal landfill. keep it away from people and even if anything goes wrong no one dies. If you dulute it a bit it wont be much use to terrorists or at least no more use than any other somewhat poisonous substance (and it will be easier to make cyanide in a lab than fly to antartica (or wherever) to dig up radioactive stuff).

Frankly any harm it can do will be dwarfed by the lives saved from slightly cheeper power (e.g. peny pinching old and cold ladies) or the displacement of coal as power (global warming) etc even though those disadvantages are les obvious.

Posted by Genius : 3/08/2005 08:37:00 AM