Alternative energy and the future (Scientific content)

psyx · 2014-02-13T02:25:27+00:00

Hey guys! So Ive been thinking about this post for a while... This post is just to get things going! I hope you enjoy the light read ? If I made any mistakes or omissions, please say so! The world needs more energy and as we approach the 3rd decade of the new millennium, things are heating up (pun intended) in the race to find alternate means of generating energy. I will briefly discuss some developments. Some of these are just my view on some of the matters and its open for debate ? Solar energy We all know this one: Photovoltaic cells. Some people think this is the road ahead and it might be, but there are other means: This method is known as thermal solar energy or CSP (Concentrated Solar Power). Dozens of "mirrors" concentrate solar radiation on a central point which transfers the heat to a next phase. This next phase can either be a steam turbine or a means of heat storage or a thermochemical cycle. Thermochemical cycles are VERY interesting and I did a study on one of these thermochemical cycles in my final year doing engineering. The University of Stellenbosch and the North-West University published several papers on these cycles. The core idea is that these CSP plants can generate temperatures of 600 to 700 degrees. This is the operating temperature range of a 4th generation nuclear power plant. At these temperatures, hydrogen can be manufactured efficiently (up to 65% thermodynamically efficient), which can be used in hydrogen fuel cells to generate electricity. Check out the thermochemical cycles: HYS cycle (My favourite) http://en.wikipedia.org/wiki/Hybrid_sulphur_cycle Sulphur Iodine cycle (Similar to HYS) http://en.wikipedia.org/wiki/Sulfur-iodine_cycle and the Copper Chlorine cycle http://en.wikipedia.org/wiki/Copper-chlorine_cycle These thermochemical cycles are some of the most efficient cycles which have been identified as options for the use in these CSP plants by the University of Stellenbosch. Nuclear energy In this day and age this has become a big taboo... The disasters at Chernobyl and Fukushima (Don't forget the Three mile island incident) are good reasons for this.There is also the concern that the development of nuclear power can easily lead to the construction of a nuclear bomb. This means that the super powers don't like it when a 3rd world country has access to these technologies. The current developments are in the direction of 4th generation nuclear power plants which operate at higher temperatures, as mentioned above. China, Russia and the USA (I think)have successfully built 4th gen plants. These plants are more efficient and also have some other applications than normal steam turbine power generation, like the thermochemical cycles mentioned above. The PBMR which South Africa was developing, was a 4th Gen power plant, but was very unfortunately canned in 2010 ☹ Thorium nuclear power plants Thorium power plants are still a bit theoretical with some pilot plants already in use, but no full scale plants having been built yet. The key benefits of this type of power is that Thorium is highly abundant, so there is almost no chance of running out of Thorium. Thorium power plants have almost no chance of experiencing a meltdown/ runaway reaction, since the reaction needs a constant source of neutrons which can be done with a particle accelerator. The beauty of this is that in the event that something goes wrong, the neutron source can be stopped and the reaction will stop. The nuclear decomposition of Thorium under these conditions does not emit another neutron which can cause a chain reaction. Also, Thorium cannot be weaponized, so its safe to entrust this technology to all countries to grant them nuclear energy. Anyway, this is just the start and two fields which I know a thing or two about. If someone can elaborate on new developments in wind, geothermal and tidal energy, please do so!! ?

lindsmuse

We need intelligence energy - focussed where it's needed. We don't need all the genius being used to add bells and whistles to our existence - making those with consumer power more comfortable ... We have geniuses here on the planet. Supercomputers. Can't someone figure this out? We need clean energy. That island of plastic and junk in the ocean (North Atlantic ) somewhere? - the junk, the pollution ... If it's about greed - isn't there someone who can figure out a way around that? (more than is being done with the incentives to companies for being green.) We are amazed at the super intelligence of some people but why are all in the do? Why isn't THAT (brainpower) being harnessed? Maybe we just too stoopid. ☹

Doomsower

The problem is that all the low hanging scientific fruit has already been picked. To push the boundaries you need dump-trucks of research funds.
The result of this is that scientists are dependent on large companies to fund research. And let's be honest these companies will fund whatever will give them a quick profitable product.
So we will spend money on building a marginally cooler cell phone and hair growth creams.
We will probably only solve this problem by advancing science as a whole. And to do that we will have to go back to doing science for science's sake.
But the US is downscaling the space program and the Hadron Collider is running out of funds.

So I say we get a boat and claim that trash island in the name of GFSA and build a lab. ?

peterleroux

Doomsower wrote The problem is that all the low hanging scientific fruit has already been picked. To push the boundaries you need dump-trucks of research funds.

Or to look at what our grandparents did instead of switching on the aircon. There is loads of 'heirloom technology' around that works without electricity- passive evaporative cooling, daylighting instead of internal lights, walking/cycling instead of driving, pressure cookers, solar cookers, hayboxes. There are some designers in the UK called Practical Action who've been designing 'appropriate technologies' for deep rural areas- that might turn out to be useful to all of us

Doomsower

peterleroux wrote Or to look at what our grandparents did instead of switching on the aircon. There is loads of 'heirloom technology' around that works without electricity- passive evaporative cooling, daylighting instead of internal lights, walking/cycling instead of driving, pressure cookers, solar cookers, hayboxes. There are some designers in the UK called Practical Action who've been designing 'appropriate technologies' for deep rural areas- that might turn out to be useful to all of us

True, there is a lot we can do to reduce our individual usage and boost self-efficiency.
But we still need loads power to run industry (and bass amps ?).
Small scale generation can't power induction furnaces and factories.

peterleroux

Doomsower wrote Small scale generation can't power induction furnaces and factories.

Agreed. And the problem in South Africa is that it's very difficult to even ascertain how much power went into making something. Just think about the chair you're sitting on- there isn't a locally-producing manufacturer in the market who can certify what percentage of the metal in your chair comes from recycled sources- and given that recycling Aluminium takes 20 times less electricity then extracting it from ore to start with, it makes a massive difference. The industry is improving but we are new to all of these things that Europe has been grappling with for ages. Luckily this gives us a chance to 'leapfrog' like we did with cellphone technology- going straight to the state of the art without paying the school fees in between

Doomsower

peterleroux wrote Agreed. And the problem in South Africa is that it's very difficult to even ascertain how much power went into making something. Just think about the chair you're sitting on- there isn't a locally-producing manufacturer in the market who can certify what percentage of the metal in your chair comes from recycled sources- and given that recycling Aluminium takes 20 times less electricity then extracting it from ore to start with, it makes a massive difference. The industry is improving but we are new to all of these things that Europe has been grappling with for ages. Luckily this gives us a chance to 'leapfrog' like we did with cellphone technology- going straight to the state of the art without paying the school fees in between

True, but Europe has not solved the problem either.

What we need to do is make informed decisions and not make rash emotional decisions.
I am reminded of the Aluminium frames around some solar panels that used more power to make than the panel can ever produce.
There was a company who produced carbon neutral clothing and some celebrity idiot sent his private jet to pick up some t-shirts from them.
And don't get me started on those horrible Prius disasters.

So to summarize don't be a hippie.

Bob-Dubery

I'm, OK with the Prius as a proof of concept. Somebody always has to take a first try at some or other technology. Costs tend to come down, and if the environmental cost for hybrids comes down then all well and good.

But this is a problem with a lot of ostensibly green things - they just move the point at which the damage to the environment occurs. Too often all that really happens is that the end user can say that they personally are "green" or "environmentally conscious" or have reduced their own pollution levels and that is true in their own private domain, but overall there is still damage, it's just occurring further up stream.

Interestingly F1 has for some years been in carbon credit despite the amount of trucking and flying they do. They do this just by funding the planting of trees to reforest areas where there has been extensive felling. You emit X carbons, you plant trees that will consume and save X+1 carbons and you're in credit. An elegant, simple solution - though it does cost them money.

F1 is also hybrid this year under the new rules. Small turbo engines with recovery of heat (exhaust and turbo) and braking energy; recovered energy fed back into the drive train; a cap on maximum fuel flow at any given time; and an absolute limit of 100 liters of fuel (which is compared to pump fuel to make sure it's not some special jungle juice) per race.

The sports prototypes (what are raced at Le Mans and similar races) have gone even further. Diesel is allowed (IIRC there is a mandated bio-diesel content). They too have energy recovery systems. The Audis race at Le Mans with LED lighting.

The racing use is significant because output from the energy recovery system is limited (though the limit has been substantially increased) and so the gain is to make them smaller, lighter, more efficient - which should feed back into production engines.

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