Quote:
Originally Posted by codprawn
The Baglan Bay power station I mentioned earlier cost £300 million to build and generates as much power as 3x the Kent windfarm. The current Kent windfarm is costing about £2 billion. So in other words £6 billion to compete with a £300 million station. Of course the windfarms don't use any fuel but it still works out 3x more expensive for the electricity.
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Codders - your economic argument is a little simplistic For any energy producing system you need to consider the cost per Megawatt produced
over the life cycle of the equipment. This cost comprises three components: commissioning, use and de-commissioning. Now your values cover only the first, and you allude in passing to the second. You've made you point about build costs but lets consider the other two. Nuclear has a higher cost per megawatt in production for several reasons:
- it uses a fuel (although not in great quantites) that is requires expensive infrastructure to refine/enrich and is problematic to ship. NB production cost for U235 and U238 are not great
- it requires greater human supervision (in case it all gets a bit hairy)
- maintenace costs are more expensive because of the hostile operating conditions, and the careful regime needed to ensure safety
Wind has none of these issues. The worst that can happen is that either the things stop spinning or the blades fall off and squash a few sheep (onshore) or seagulls/Ribnet members taking a closer look (offshore)
Whilst were talking about production costs though we need to look at reliability. Granted wind is an unreliable source - hence my previous post about diversity. In this case of I'm thinking about using dual-reservoir hydro-electrics as giant storage devices. This is precisely what has to happen with nuclear as they have to run pretty much the same output all the time. Now clearly power demands are much higher between 8am and 6pm so having the facility to increase supply at peak times is an essential part of the mix. We need a diverse range, with the option to store energy in the the glut periods for exploitation in the lean ones. We think nothing of storing gas, and petrol/diesel, in large quantities to smooth out peak and troughs in the supply/demand cycle. A similar approach to energy storage in general would make many of the renewables a much more attractive option
Now to the final cost sector: decommissioning. Now for wind this is very low. However, this is the part that some exponents of nuclear either conveniently forget to mention, or gloss over by saying - "the technologies of the future will allow us to solve this problem". Well ... we've know that burning fossil fuels will cause global problems for decades. Furthermore we are starting to see real global effects as a result of man's activities (a fact even conceded by the Bush administration before he left office) and we should have had years to develop the technology to deal with it ... BUT, we haven't (yet). Leaving nuclear residue as a massive problem for future generations is not IMHO acceptable. So if you want to go Nuclear, do so on a limited scale so that the mess you leave behind is similarly limited. Bear in mind that its not just the old fuel that is an issue, much of the reactor infrastructure will also be highly radioactive. Already there is a lot of radioactive waste in the world (probably even more than Polwart's Afghans can deal with
) . This part of the equation is the real unknown; to date the number of nuclear plant built far outweighs the number decommisioned and even now the only solution to radioactive waste appears to be bury it in the ground and hope we can do something with it later
You may be interested to learn that even today students of Science GCSE are taught about true life cycles costs of energy generation, rather than just the headline build figure. Its a really useful exercise to understand the real costs
As to your comment
Quote:
Originally Posted by codprawn
As to the old few thousand years halflife argument as a Physicist you should know that the longer the halflife the more stable the material.
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.. you confuse stable with harm. I could cite any number of stable fields or beams that produce an output at either a constant (or constantly decreasing) rate and all of them would be fatal to you. It could also be argued that no radioactive material is stable - the decay of each atom is an entirely random process. It is only when taken as an aggregate over a large enough population of atoms, that a degree of predictability is observed. In the case of nuclear decay this leads to the concept of halflife. Now with a very long halflife the output appears relatively constant over any practical observation period. However, quasi-stable or not, if the isotope in question happens to be emmitting high intensity gamma streams then unless you a confortably settled in your lead-lined bunker its still going to do you harm.
Don't get me wrong - I'm not completely anti-nuclear and completely pro-wind - far from it. I just want to ensure that we (as a populus) have the necessary information to conduct a reasoned debate about energy generation, and not just rely on the latest Daily Mail-esque headline.
No one energy generation method is the panacea (unless they get room temperature fusion sorted in the next half hour). At least tidal has a degree of predictability about it, but biomass, solar and wind should all be considered in addition to fossil fuels and nuclear. It may yet turn out that if wide scale solar can be economically commercialised then some of poorest parts of the world may turn out to be asset rich (due to the high amount of sunlight they receive).
I know Codders that you have cited the local solar array on a neaby Tesco and its poor cost/yield ratio. Now I'm speculating, but I suspect that those are photovoltaics - a technology that is still only finding its feet. In contrast though if solar is used to simply provide heating (photothermal) these can be very effective (even on overcast days in winter due to their being able to utilise most of the visible spectrum of light). Were this type of technology widespread then a significant proportion of the domestic energy requirement for heating could be mitigated. Couple this with better domestic insulation and you are starting to make a real difference. Just consider the roof area of all the houses in the UK, if just 1/4 of that could be covered with "cost effective" photothermal panels just think of the savings. The key however is cost.
Given the billions that are being used to pump prime the economy surely a fraction of that could be used to advance the cause by developing production methods to reduce photothermal unit cost and to start to develop viable energy storage capacity.
Apologies to all for the essay on energy policy. I'll get my coat
and a gent who works in the industry piped up with some interesting info.
