Alternative energy and the future (Scientific content)

psyx

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!! ?

21Fretter

Hasn't it been found that nuclear energy is often one of the cleanest forms of energy generation i.e. despite the disasters, the amount of energy that is generated versus the amount of pollution and damage that occurs when there is a disaster far outweighs the benefit/cost for coal and other methods?

AlanRatcliffe

Whatever the source of more power in the future, I think something which is going to be important is the space it takes up v the amount of power generated. This will rule out wind and solar farms for the long haul IMO.

Nuclear is definitely our best solution ATM, but the safety issues are obviously a concern - even if accidents rarely happen, the few times that they do are catastrophic. And you can never rule out human stupidity or greed in these matters (Koeberg being built in an earthquake zone is a prime example). A completely safe nuclear solution such as thorium (or the much anticipated, long awaited cold fusion - if it ever happens) will be a game changer.

Of course with modern advancements being what they are, it's entirely possible that the solution will be something no-one expects, coming from a new, as yet unknown technology that is impossible to anticipate.

Look to Star Trek I say! ? They have been better at predicting the future technology than any methods based on hard science (maybe because they work on the social and societal needs of people, rather than basing predictions on existing technology). Computers, communicators (cell phones and tablets), hyposprays, machine translation, speech recognition, artificial sight, video conferencing, heads up displays, 3D printing, etc.. So where's my holodeck, bitch?

peterleroux

The other side of this is simply using less electricty - a lot of our answers don't lie in looking forward to future breakthrough but looking back to previous solutions - making use of good, existing (but possibly uncool) technologies like direct solar heating (solar geysers, Trombe walls) and evaporative cooling (like swamp coolers and charcoal coolers). Even just switching over to low energy lighting knocked ten percent of my household energy consumption.

Two generations ago we didn't rely on unlimited electrical supply, and I suspect in two generation's time we won't either.

AlanRatcliffe

+ 1 on the lower power thing. We're slowly but surely moving in that direction, with green building standards too.

Something that we haven't started doing and I wonder why, is low voltage DC house wiring. The vast majority of devices in our homes these days (with a few obvious exceptions) are running off 5 V or 12 V, but we're still running 220V to everything and using transformers to step it down for each individual device. I know it's more the amps than volts, but surely just being able to plug things directly into a low voltage supply and eliminate a bunch of lossy voltage conversions will save a heap of power being wasted? It will also make having a small array of photovoltaic cells a lot more usable for the average home. As a bonus to audio enthusiasts, it'll mean a lot less EMF pollution in the home too.

Doomsower

Alan Ratcliffe wrote: + 1 on the lower power thing. We're slowly but surely moving in that direction, with green building standards too.

Something that we haven't started doing and I wonder why, is low voltage DC house wiring. The vast majority of devices in our homes these days (with a few obvious exceptions) are running off 5 V or 12 V, but we're still running 220V to everything and using transformers to step it down for each individual device. I know it's more the amps than volts, but surely just being able to plug things directly into a low voltage supply and eliminate a bunch of lossy voltage conversions will save a heap of power being wasted? It will also make having a small array of photovoltaic cells a lot more usable for the average home. As a bonus to audio enthusiasts, it'll mean a lot less EMF pollution in the home too.

The thing is the devices that use the most energy use AC (kettles, stoves, geysers and aircons).
The lower power item tend to use DC.
With each down conversion to DC a little power is lost as no transformer is 100% efficient.
Power has to be provided in AC format anyway so doing another high voltage conversion would be wasteful.

Plus high power DC is a lot more dangerous than AC.

Shibbibilybob

Personally, I am a big fan of nuclear power. I think it is currently our way forward, although perhaps temporarily.
I anticipate a big movement away from the grid. Whilst we need obviously invest in wind farms, tidal generators, solar and the like, none is currently viable as a replacement for coal, but these early prototypes and proofs of concept are obviously necessary for developing systems of these types that can ultimately replace coal in powering the grid.
In the mean time, it would be nice to see a lot more private generation of power, not to supplement the grid.
Things like solar panels at home, or a small turbine in your garden that supplements the supply to your geyser, and so on. These mechanisms are still expensive, for their generating capacity, but rich private individuals can afford such things, and I would like to see these paths promoted.

Personally, I think the environmental cost of nuclear power is considerably lower than that of coal power, with waste that is of almost zero volume comparatively. It comes with it's own set of risks and dangers, but to me it seems our most viable avenue.

peterleroux

Something else that Eskom needs to do is enable reverse metering, so that if I produce excess electricity it's easy to sell it back to the grid. Aside from the tax incentives, it's the ease of selling power into the grid that has made solar so popular in Germany- they have the biggest installed base of solar PV in the world, because it's easy to make the case for earning passive income

psyx

The problem is that Eskom is eyeing the shale gas in the Karoo as a source of gas to power a combined cycle gas turbine station. We did a publication on this last year. Eskom cannot afford to build nuclear power stations, so powering a CCGT plant with fracked shale gas is becoming very lucrative...
So yeah... Fracking
Can of worms opened

evolucian

Is there any water in the Karoo? Not being funny btw, its just the eventual pollution of the chemicals used and the gas giving us free soda streams not fit for human consumption... kind of a concern, for me at least. After watching Gasland, I am wary of that stuff, lol. So if any of those techniques and chemicals are used... bleh.

Anyone made progress on magnetism yet? The earth is magnetic so why go against it. Is AC really that bad? Is it perhaps that they just haven't wired it well or designed it well to get the use of returning energy? Still a noob at this but attempting to understand more.

I for one don't like nuclear power, especially in the hands of our countrymen who will have to build it. When buildings fall apart, the notion of having them build that kind of power plant gives me enough faith in their ability to pull it off much like a seahorse doing a butterfly stroke.

Why can't people make something that doesn't break? Anyway, its a fun and interesting notion this free energy. You guys are clever n stuff... work on a car motor that won't break. Then go one step further and work on levitation by tuning magnets to the earths frequency et al. Get rid of crude oil completely. If you're paranoid, like myself, that they'll send someone over to kill you for upsetting the apple cart... appoint someone you don't like as spokesperson who can pretend he owns the company and idea. Each assassination brings on a new owner... come on. It's perfect...

G-Man

I know this doesn't quite fit in, but it is a graphine battery. It's really a super capacitor but with really fast recharge times. Might be the answer to the electric car problem.

http://www.technologyreview.com/view/521651/graphene-supercapacitors-ready-for-electric-vehicle-energy-storage-say-korean-engineers/

GuitarDoge

Now that I've seen this thread I can add some stuff:
Solar power - Large areas needed, expensive. Viable if much more efficient panels are produced.
Wind power - Very little power produced and makes bats implode due to creating a difference in pressure, not very viable.
Hydro-electric power - Very viable in areas with big dams, not many in the world.
Gas power - if natural gas(methane) can be extracted will no bad effects(ie not frakking) it's burns quite cleanly.

However all of the energy sources above require certain conditions and often produce little power.

Nuclear power: This is probably the only way to meet energy demands in the future. Even if we all cut our energy usage by a third, the population will quickly catch up...

Modern fission nuclear reactors are much, much safer than the older designs, take up a relatively small space and offer plenty of power. The waste is very harmful but not that much is produced and it can be stored safely for now.

Perhaps the perfect power source is nuclear fusion. This produces no harmful waste and produces massives amount of energy., and the reaction isn't sustained if an accident occurs, unlike a fission reactor. And even though this is still in development it's actually happening right now! Just google iter ?

Bob-Dubery

peterleroux wrote: Something else that Eskom needs to do is enable reverse metering, so that if I produce excess electricity it's easy to sell it back to the grid. Aside from the tax incentives, it's the ease of selling power into the grid that has made solar so popular in Germany- they have the biggest installed base of solar PV in the world, because it's easy to make the case for earning passive income

This is easier said than done - but then so are many worthwhile things. It was tried in the UK but there were problems early on. An energy supplier can't allow just any old current into the grid and just any connection to the grid.

There need to be standards - your equipment must have output like X and it must be connected like Y. Those things tend to work well in first world countries where a majority of people see the law as a contract between government and citizens. In places like SA where attitudes are more laissez faire it maybe is not such a good idea. We'll get the cheapest sparky (who has an uncle who will write out the necessary certificates for a fee) to hook everything up and if we don't electrocute ourselves we'll blow up the nearest street box.

I have some idea of what I'm talking about. When I bought my current house I got a compliance certificate for the electrics. Sweet. Then I started noticing and uncovering odd things (like some plugs on the same circuit as the geyser). I eventually phoned the Electrical Contractor's Board and had a chat. They were very interested in the guy who had signed off the certificate. They'd had a lot of complaints about him, and they said he was signing so many certificates every day that he couldn't possibly be inspecting every house he signed off on. It turned out that he'd never set foot in my house. The sparky who'd been working there (and had hooked up the wall sockets to the geyser) was trained in Mozambique, licensed to work in Portugal but not in SA and just had an arrangement where he'd phone up some oke in Pretoria, tell him the wiring in such and such a house was tickety boo and the oke in Pretoria (a private contractor, not a government official) would write out a certificate for 500 bucks. He found out that writing out certificates for a house he'd never set foot in was good business and meant he didn't have to do inconvenient things like driving around and looking at stuff.

There's also a problem here with lack of regulation around solar panels. There is an SAB standard, but it's not mandated in law. So the market is awash with cheap panels that may or may not generate nice clean power suitable for feeding back into the grid, and which might come from countries where they have rain but not violent storms like we have on the Highveld. Get something with the SAB stamp and you can have a fair degree of confidence that your panels will survive the first hail storm - but you'll pay more for that quality.

Eskom do give rebates on solar water heating and heat pumps that meet certain standards and are installed by an approved supplier. So there is some recognition by them of the efforts that people make to reduce the load on the grid.

No such rebate for a system that somebody tried to flog me a while back that, he claimed, would free me from City Power forever and which magically generated electricity from ionised water (which I would have to buy from him). Apart from it sounding too good to be true there were two other problems. The first was that there was no demonstration site so that I could see the thing actually working. The second was that the pictures all showed a big fat cable connected to the distribution board. This, I was told, was a legal requirement imposed by Eskom - your magic box that generated all your electricity had to itself have an electrical supply.

There are lots of little things that each of us can do. Power saving globes for example. Getting into the habit of not burning lights that you don't need at the time. Individually these result in a reduction on your electricity bill. If enough people do those little things then it adds up to a big whole and reduces demand on the grid.

peterleroux

X-rated Bob wrote: There need to be standards - your equipment must have output like X and it must be connected like Y. Those things tend to work well in first world countries where a majority of people see the law as a contract between government and citizens. In places like SA where attitudes are more laissez faire it maybe is not such a good idea. We'll get the cheapest sparky (who has an uncle who will write out the necessary certificates for a fee) to hook everything up and if we don't electrocute ourselves we'll blow up the nearest street box.

The low standards of compliance around electrical installations generally are a concern. There are a few different opinions around how practical this would be but it's a little academic until Eskom allows at least a trial in a pilot area.

A little birdy tells me that if you have the old-fashioned spinning disc meter, you CAN feedback into the grid and the meter will turn backwards, but your service provider will come and ask interesting questions if your net consumption is negative. No luck if you have a digital meter.

X-rated Bob wrote: ...I have some idea of what I'm talking about. When I bought my current house I got a compliance certificate for the electrics. Sweet. Then I started noticing and uncovering odd things (like some plugs on the same circuit as the geyser). I eventually phoned the Electrical Contractor's Board and had a chat. They were very interested in the guy who had signed off the certificate. They'd had a lot of complaints about him, and they said he was signing so many certificates every day that he couldn't possibly be inspecting every house he signed off on. It turned out that he'd never set foot in my house...

This is a big weakness in our system- electricians certify their own work, and government takes their certificate of compliance at face value unless someone complains. In other countries, a government inspector will issue the certificate after inspecting the work. Even on corporate sites I've had to kick electricians off jobs because they were issuing CoCs that didn't match the work they had done.

X-rated Bob wrote: ...Eskom do give rebates on solar water heating and heat pumps that meet certain standards and are installed by an approved supplier. So there is some recognition by them of the efforts that people make to reduce the load on the grid. ...

Which is coming to an end, unfortunately. It still pays you to install an energy efficient geyser, but the payoff takes longer without the rebate.

IceCreamMan

Nucleur has to be the way to go.....my only concern is the relative lack of top class scientists in ZA. The top guys all move internationally to study in their fields*. The idea of scientists produced by our 30% pass rate system kinda scares me a bit ?

*in no way am I insulting ZA scientists in ZA by this. We have excellent scientists but the current regime seems to foster stupidity more than it does intelligence.

Bob-Dubery

I never worry about the scientists who build reactors. They get pulled into the project in whichever country on a contract, get the thing designed and built and tested and then move on.

It's the guys who remain to run it that I would be more inclined to worry about. It too often turns out to be a case of paying peanuts and getting monkeys (or Homer Simpsons).

But the newer reactor types are far less prone to melt down so safer. But that won't satisfy the populist prophets of doom who get frothy mouthed about anything with the word "nuclear" in it.

Sometimes I think that quackery is the real problem. Look at the damage done by the scare over the three-in-one vaccination in the UK. My local residents association is responsible for the propagation of pseudo-science pertaining to electromagnetic radiations which leads to the further dissimulation of quackery in schools and decreasing 3g performance in the suburb because of the protests that erupt anytime anybody wants to build a mast for anything. These people go around telling school kids that cell and microwave towers will kill trees and various other living things (like school kids), but about a mile from one of the schools where they preach this message is a post office with two notable features - a whole load of masts around the back and some very healthy looking invasive trees growing between them.

What does give me hope is that the mumbo jumbo around HIV that Thabo Mbeki embraced has been largely abandoned by the current government and management of that disease is now markedly improved. There's still been a huge price paid that needn't have been, but at least the pseudo science has been reversed and future damage will not be nearly as great.

GuitarDoge

The beauty of a nuclear fusion reactor is that if it breaks, almost no long term radioactive pollution is released. It really is the future when one bath tub of sea water can power a city for a year.

Also, none of the fuels in a fusion reactor can be weaponized.

And luckily, South African universities don't have a 30% pass rate and are still up to good standards. ?

Education is key for dealing with any problem.

IceCreamMan

GuitarDoge wrote:

And luckily, South African universities don't have a 30% pass rate and are still up to good standards. ?

I have worked at a tertiary education facility, I don't share your optimism..,, the ramifications of a 30% pass mark required is felt everywhere.... I have seen students graduate even though they have failed....

GuitarDoge

IceCreamMan wrote:
GuitarDoge wrote:

And luckily, South African universities don't have a 30% pass rate and are still up to good standards. ?

I have worked at a tertiary education facility, I don't share your optimism..,, the ramifications of a 30% pass mark required is felt everywhere.... I have seen students graduate even though they have failed....

I'm studying electrical engineering at the moment and it's much tougher than school...and I seem to be learning the right stuff...

Bob-Dubery

IceCreamMan wrote:
GuitarDoge wrote:

And luckily, South African universities don't have a 30% pass rate and are still up to good standards. ?

I have worked at a tertiary education facility, I don't share your optimism..,, the ramifications of a 30% pass mark required is felt everywhere.... I have seen students graduate even though they have failed....

Well... the word "university" is more liberally applied these days. What used to be Technical Colleges (then Technikons) are now "Universities". I studied first at Technikon and I don't feel ashamed of it or anything, but years later I enrolled at UNISA which still teaches at traditional university level and jikkel! There's a difference.

This is a game being played by politicians all over the world. They promise you that Little Johnny will have a better education, a better shot at tertiary education and blah be blah. But they can't make the Little Johnnies of the world any brighter, so they dumb down education systems, force marks to fit curves and so on. There's been repeated complaints in the UK where A-level pass rates rise and rise and rise, but the universities see more and more first year students who are barely literate and numerate.

Not good. But the old way of doing things is too easily labelled "elitism" and who wants to be tarred with that brush?