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Entry 708, on 2008-02-27 at 22:08:54 (Rating 1, Science)
A panel of engineers was recently asked to list the most important aims for the 21st century. They came up with some interesting ideas. Some were obvious and others were a bit bizarre. Here's the list, and my comments on it.
Developing cheap solar power was the first aim. Ultimately most of our energy comes from the Sun. Coal is solar energy locked up by plants in the distant past. Wind power is powered by the weather patterns caused by the Sun. Hydro power uses falling water evaporated by the Sun. Geothermal and nuclear power don't rely on the Sun but they are minority sources.
It seems logical to capture the Sun's energy more efficiently by converting it directly instead of waiting for it to change to another form first. Solar technology is constantly improving but it isn't cheap enough yet. Note that the aim is to make it cheap, not to make it efficient, although the two are connected. I think this is a worthwhile aim although it might be made redundant if the second aim is achieved.
Making fusion power practical was the second aim. This has been an objective for many years yet but the issue of controlling the energy released has always been difficult. The problem (ironically) is that fusion involves too much energy - temperatures in the tens of millions of degrees. But if fusion can ever be made to work reliably, efficiently, and safely it will solve all our energy problems forever.
Hydrogen fuel for fusion will never run out and dangerous radioactive waste isn't a major issue. The abundant electricity produced could be used to electrolyse water and produce hydrogen to power vehicles. And burning hydrogen just makes water - there's no carbon. Unfortunately fusion has been on the horizon for many years now and just doesn't ever seem to quite arrive. But it will one day and no doubt that will be in this century.
The next aim is carbon sequestration. That involves capturing carbon produced by burning carbon-based fuels (coal, oil, petrol, gas) before it is released into the atmosphere. As I said above, if hydrogen can be produced efficiently then using carbon fuels will no longer be necessary so this might be a short rather than long term requirement.
Aim number 4 was to manage the nitrogen cycle. I'm not sure entirely what they were getting at here. I guess it is to do with fertilisers used in agriculture which are produced at great expense and with a lot of carbon emission through fuel burning. This one also gets back to energy production and might be minimised if cheap, renewable energy sources can be perfected but there could be more to it that I am unaware of.
Managing water resources was next. This is a bit too general to be a real aim, I thought, but there is no doubt that water supply is becoming a problem in some areas of the world. To some extent this is due to global climate change so managing greenhouse gases might be helpful.
The theme here seems to be that all of these aims are inter-linked. For example, more solar or fusion power would reduce the need for capturing carbon which would reduce climate change and help manage water shortages.
Number 6 was to reverse engineer the human brain. This is an interesting one. Some people believe this aim is closer than we might think. There are many deep philosophical issues associated with this being achieved. Would a machine with a human level intelligence be conscious? Would it be alive? What rights would it have? That's a subject too big to cover in this brief overview. Maybe a later blog entry is required.
Next was to prevent nuclear terrorism. I don't know whether this is really a scientific or engineering aim as much as a political one, but science can help, of course.
Number 8 was to secure cyberspace. As a person who lives on the Internet I don't see this is as big an issue as some people believe. There is no doubt that hackers and spammers are a nuisance but I don't know whether fighting their activity should really be elevated to a major aim for the century.
Number 9 was to enhance virtual reality. This has been quietly happening for many years and I don't think a big breakthrough is necessary. It will just happen naturally as existing technologies are enhanced. So again I don't think this deserves to be stated as a major aim. Maybe we should look at the bigger picture of building better human-machine interfaces instead. These would almost certainly involve VR to some extent.
Number 10 was to improve urban infrastructure. I have two problems with this. First, it is too general; and second, it is a constantly changing phenomenon anyway and no specific aim is really required.
Next was to advance health informatics. I don't think this is too difficult from an engineering perspective. Its more a political and social issue involving funding, reliability, security, and ease of use. I think this could be solved today if the political aspects could be resolved.
Producing better meds was aim number 12. The trend here seems to be towards medication customised to the individual and that will probably be the biggest immediate change. Nano-scale drug delivery mechanisms also look interesting. We do need a revolution in this area because drug resistant bacteria and other issues are becoming more of a problem today.
To advance personalised education was number 13. As the world becomes more complex people will require more education to fit in. Or will they? Intelligent robotic and computer systems, better information sources, and more specialised employment might make more education unnecessary. I don't think anyone would deny that better education is a great goal under any circumstances but it might not be quite so important as we move past the industrial era into one where few people will need to work.
The final aim was to explore natural frontiers. I really don't know what this means but it sounds like a good idea, because all forms of exploration are good, so I will agree its a worthy aim!
That's it. Its not the list I would have come up with but I'm not an engineer so I guess my perspective would be different. Also, progress can only be made if political, social, and environmental aspects of our civilisation are also considered. And lastly, predictions of the future are notoriously difficult so I wouldn't be surprised to find that half of these are irrelevant in 20 years time.
Comment 1 (1193) by Anonymous on 2008-02-28 at 14:01:03:
Thank you for this opinion on an interesting topic. What I want to ask you is this: where does the hydrogen fuel for fusion come from? I know there is hydrogen in water (H2O) but doesn't it take more energy to extract it than can be gained from burning it? How do we gain energy by using hydrogen fusion?
Comment 2 (1194) by OJB on 2008-02-28 at 15:52:11:
You are confusing nuclear and chemical energy. Fusion doesn't "burn" hydrogen, it fuses it. Chemical reactions just rearrange the electrons and involve small amounts of energy. Nuclear reactions involve hugely more energetic processes which affect the nucleus of the atom (or plasma since atoms don't exist at those temperatures).
If we electrolysed water to make hydrogen then burnt the hydrogen in oxygen to get back to water you would be right. But using energy created by fusion to electrolyse water then burning it you get a huge net gain of energy. Effectively the hydrogen is just a way to store energy.
To give you an idea of the relative efficiency of burning and fusion consider this: if the Sun was made entirely of coal it could produce its current output of energy for 6000 years (if the oxygen came from somewhere else), but because it is using hydrogen fusion instead it has already produced energy for 5 billion years and has still used less than 1% of its total fuel!
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