[thedoc (OP)]

Peter Steadman asked the Naked Scientists:
   
Just wondering with green power, has the technology evolved to a point where if we construct thousands of windmills today say, there wont be major advances tomorrow in more efficient, cheaper, windmill.2 leaving our stock out dated?

Would it not be better to utilise advances in new reactor types where you can produce bio-fuel as well as electricity from excess heat in the reactor. And just stick to what we have or fracking until they are constructed.

There are some solar and windmill already to cite to the hippies. I had a dream not long ago where there were no power stations. Each street generated its own power. I liked the idea of down scaling the problem, this shortens the infrastructure of a "singular cell" to the length of a street.

It is really tricky typing while listening to your show.

Peace,

Peter Steadman/me
What do you think?

[CliffordK]

It depends on who is paying.
Anything the government touches gets more expensive every year rather than cheaper every year.

I agree that a lot can be done with local energy generation, although there are many advantages of being connected to "the grid".  Around here, my peak energy needs are in the winter when solar energy is less than adequate.  Fortunately water flow increases and hydroelectric power generation increases in the winter,, but very few of the population would be able to generate 100% of their power needs from micro hydro plants.

I do believe that when bring power to 3^rd world nations for the first time, more emphasis should be put on micro power generation projects.  Once the grid is here, it is more difficult to disconnect.

Some advantages of "grid attached" alternative energy include using the grid as a battery.  If I chose an off-grid power installation, I certainly would need a very expensive battery bank, and might need to size all my power generation to 150% of my needs or so.  A large scale power project would need much less redundancy. 

As far as waiting 20 to 50 years, then buying into the wind, solar, and etc.  Much of the prime real estate will snapped up in the next couple of decades.  What will be left will be more expensive to develop and less productive.  Research and advancement doesn't always occur on its own.  Without the R&D to date, and in the next few decades, one could not expect alternative energy systems to advance.  Some of that advancement comes from actually building the systems, and seeing what is effective, and what is not.  And, of course, generating a revenue stream.

Furthermore, it is easier to build new than to replace existing systems.  A system that is optimized for hydro, NG, or coal may not be designed for wind and solar.  Furthermore, what should one do with the existing power plants?  Why invest in new NG and coal plants today and expect to phase them out in 20 years?

Personally I believe hydro and solar would complement each other, and that hydro flow could be reduced on sunny days and increased at night, but unfortunately none of the systems seem to be designed and implemented with that in mind.  Even smart thermostats may be counterproductive by increasing peak grid demand.

Without very expensive R&D in Fusion energy today, we will never have fusion energy in the future.  One can't just wait for it to come.

[Peter Steadman]

Hi, thank you for your reply!!

Are you more fusion and less fission?
The state should build a power station that burns dominos pizza menus, There free and I get posted so many, they could power Europe never mind just England, lol.

There was an interesting programme on the BBC the other night about predicting earthquakes. There was a researcher on, that was trying to work out why the sky would sometimes glow before an earthquake. During his investigations he found that when rock -I think it was granite he was using, was put under stress to almost failure it will produce an electric current.
The charge this process produces never depletes.
 Could we use his findings, gravity and the mass of rocks in the earth’s crust to produce a free source of clean energy in the future?

It's a shame we don't have hot springs to create geothermal power!

Is there much energy wasted in impedance in the grid, if so I wonder the cost of that waste?
I wonder what the scrap metal value of the whole grid would be?
It's a shame that the energy of falling rain can't be converted in to electricity, it would be ideal in Britain, lol.

Car makers have seem to be investing heavily in to energy efficiency, could domestic households adopt any of their findings? It would probably be very expensive, but would it be possible to have a central battery in a house that supplies lighting etc. Then connected to it multiple dynamos that charge it, that are placed every were. For example, fitted to water tank and toilet filling system, sink, bath and shower taps so when water is run they charge, even fitted to door hinges and if possible under the floor; that converts walking in to charge. -Possibly hydraulic pads that alternate in lay out, the pressure of a foot pushes hydrophilic oil from one sac through a tube with dynamo, to fill one two steps ahead-. Down pipes on guttering, unused heat from cooker, fridge, boiler.... and on and on …........  There is so much wasted energy in a home, it's a shame it's not utilised.

Your first comment - depends who's paying? I agree with you, It's just a shame there is a constant trade-off with progress and cost. It would suggest that the future generations and longevity of our environment has less value than today, lol.

I find it fascinating the way the architecture can be exploited on tall buildings to create powerful through and up drafts that are then used to spin a turbine for power. People protest at the site of turbines so this will wind them up more, and cost would be high. But, in theory could the ground around turbines be landscaped in a way to increase efficiency or even 'amplify' -for the need of a better word- low winds?

[CliffordK]

Hello Peter, welcome to the forum.

If the average house uses 2-3 KWh per day, that is quite a bit of power.  It will take a lot more than walking to the bathroom a few times a day, or capturing the rainwater runoff from a few downspouts, although certainly every little bit helps.

One of the things that autos don't do very well is "standby power consumption".  A 50 year old car might be able to sit for a year without draining the battery.  A modern car can have troubles with sitting for a few weeks, or perhaps a month or so. 

Likewise, some estimates are that 8 to 10% of total power consumption is from "standby power".  I'm not quite sure where my TV or VCR remotes are, but they faithfully wait for that remote activation.

If one chooses solar, then conservation is a very important first step.

[Peter Steadman]

Thank you for the welcome and your replies they are very informative. -

I just read an article at http://lasermotive.com/technology/power-beaming-overview/ [nofollow]. I found it fascinating that laser light can be aimed at specialized photovoltaic cells that can convert the laser light into electricity. It left me thinking...., could this be the precursor to the concept of the grid of the future?

Rather than a mass of hi-voltage cables running the length and breadth of a country from a direct out-put from a power station. will there be a mass of underground fibre optic cables originating from a 'laser-station', that delivers laser power to  photovoltaic conversion stations in every town that convert it back in to electricity for consumption? -Or, maybe to even to each building.

Some advantages would be improved safety, no visible 'buzzing' pylons and the removal of impedance in the network. I'm unsure with our current technology if there will be equal power in as out at the point of conversion. The biggest disadvantage would be the colossal cost.

Hypothetically writing, if this system was in place. Could renewable's like wind, power such lasers?

[CliffordK]

There is some loss of power with lasers in the air, especially at higher intensities.  Likewise, there is also loss of power with fiber optic cables.  Open air lasers, of course, are also affected by humidity, fog, and clouds.

The most efficient solar cells are also just under 50% efficient under ideal conditions.  Most of the super high efficient solar cells are triple junction, or perhaps even quad junction solar cells.  A laser could be tuned to the ideal wavelength for the receiver cell, and thus one wouldn't need multi-layers.  Nonetheless, I wouldn't expect much more than 50% output efficiency.  Laser efficiencies seem to be somewhere around 50 to 65% efficiency, perhaps less for high power lasers. 

Anyway, 0.65*0.50 = 0.325 energy conversion efficiency.  If transmission losses would be another 50% loss, one gets an overall system efficiency of 15% or so.

Our existing grid does incur losses too.  However, according to this doc the grid losses amount to about 6.1%, or 93.9% efficiency.

Anyway, the fewer power "conversions", the better.

[Peter Steadman]

I've just read their fact sheet, I turns out that laser's can bean power from space.
Wow the possibilities!!!!  A  huge or even collective solar farm(s) in space, beaming free and carbon free power to conversion stations on earth. The carbon footprint of its construction would probably break some records though lol.

Is the deterioration from atmospheric dust and the current efficiency rate a good trade-off considering the advantages? 
It would be saving valuable real estate on earth for food production, accommodation etc. Which will help with the predicted food shortage and water wars from over population. Plus, if power consumption increases as time evolves then the station can be expanded with out environmental concerns due to it not being limited by a shortage of space.

One other advantage is that the dangers of nuclear power can be eliminated as plant's could be located in space.

But, one major draw back would be its vulnerability to attack.

It would be expensive to build and service, but the advances in UAV's by then may help to cut those costs.

[Peter Steadman]

dam clouds

[Peter Steadman]

I've just done some further reading – is it possible to fall in love with a technology?

It's still in the early stages of R&D but According to http://www.nlight.net/nlight-files/file/technical_papers/SPRCS05_stanford.pdf [nofollow] they have already achieved 76% power conversion efficiency at 980-nm, and that increases to 85% at -50c. Possible future conversion efficiency rating could make it viable transmission of power.

Their flight of the quad-chopper is cool! 12H flight, allowing smaller battery just to cover beam interruption, there for larger payloads. You would be able to have search and rescue UAV's airborne  indefinitely, weather permitting.

Once systems are in place the power its supplies would be 'free' to a point.  military applications – like the navy being able to power fleets of ships from space located lasers, saving them the cost of fuel. Though I would Imagen the ships would be dual fueled, conventional methods for hostile engagement and laser power for taxing to locations around the globe - would no doubt push the technology to its limits and allowed by a large defence budget for its R&D. This could give current ship mounted laser weaponry dual capability. As well as the defensive capability, it could be used as a wireless power transmission.

Do you think this technologies destiny is to come in to being?
Which would be more likely, an elevator to space or laser power? Are you Dupree?

[Peter Steadman]

Sorry, have digressed a bit from the topic of the forum room.

Back to generation.

Was just thinking, hydro power production is reductive to getting energy from rain, just not falling rain. Lol

Was wondering, is the ability of rock to generate a current when it's compressed to nearly failure is universal to all matter? If so, are there other materials -or even liquids- that can produce a higher out-put?

Plus, if this is happening in the earth’s crust naturally, what effect does this have on the iron core of our blue planet, or vise versa?

[CliffordK]

Was wondering, is the ability of rock to generate a current when it's compressed to nearly failure is universal to all matter? If so, are there other materials -or even liquids- that can produce a higher out-put?

I'm not sure of the answer to all of your questions, but look up piezoelectric on the web.  Many BBQ lighters use the piezoelectric effect to generate a spark that then is used to ignite the fuel.

As with many things, energy is released with change.  So, merely compressing a rock will not give constant current output, but the action of bending and releasing will generate pulses. 

[Peter Steadman]

Hi, thank you for your reply!

 I've had a look at the piezoelectric effect, thank you its really interesting. this effect must be related to it, but I'm unsure if it's the same as it.
Below is a link to the programme I saw the research featured on. If you click on it, and forward to 41:20min you could see the findings. It sounds crazy, but the current is constant from compression, this is why I don't think its the same thing. 

If this happens deep in the earth’s crust combined with the iron core, wouldn’t this produce an electromagnetic field?

Check it out the findings are amazing – 41:20
 

[yor_on]

That one was new to me. Found http://www.earth-prints.org/bitstream/2122/3508/1/1anastasiadis.pdf  discussing it (2007)

I don't think you can use it for producing energy for us though?
Seems easier to use the heat from Earths interior than that, but maybe you can use it to predict earthquakes?

[Peter Steadman]

Cheers for that, It's interesting that there is a correlation between structural damage and PSC. Though, it's just a correlation and not definitive proof of causation, it's still pretty compelling.
The Dionysos marble composition that was used in their experiment contained, 2% quartz and 98% calcite, - two piezoelectric materials.

 It suggests that this phenomena is created by the piezoelectric effect, with the structural damage being the difference maker that provides the change needed for an instant of energy. Yet the output is not pulsed, and the output current is not irregular. So, structural damage must be uniformed, predictable and produce an uniformed collective releases through time that can create an illusion of continuity in the output flow. - This seems to ordered.
 
Though it's just a guess. - I tried looking for the dude's paper from his experiment in the program, I could not catch his name, the more I listen to it, the more his name sounds like just noise. Even if I could catch it, doubt I could spell it. - no offense intended to him, lol.


 I wonder what rock he used, and, do materials that don't contain piezoelectric crystals still generate PSC?


Saying that....., I just watched 'dude' on the video again. He states, “as long as the load stays on the rock the current will flow”. If it is fracturing that is producing the current, then the load would end up overcoming the rock and cause major failure stopping the current. It's just interpretation – but I did not feel that he meant that the rock fails after time. Maybe - it's a form of 'fractal failure' that has no end? lol.

[alancalverd]

Late entrant here - been on holiday!

You need to start by carefully defining the problem. Most "green energy" debates go on about electricity but most of the artificial energy we use is not electricity at all. You then need to determine the target per capita power consumption. This currently varies between 0.5 (Philippines) and 8 (Canada) tonnes of oil per person per annum, depending on the country you are considering. World average power usage is about 1.5 kilowatts per capita but a western lifestyle demands at least 5 kW per person.

Now we hit the problem of distribution. To provide the UK population with 5 kW/capita of renewable power would require covering the entire country with windmills, which would be unpopular to say the least. You might manage in the USA where the mean population density is minute in comparison, but you still have the problem of energy storage and you'd need an uneconomic grid to connect all the desert windmills to the urban populace. 

You can't run most industries, hospitals, or trains on unreliable energy, so you'd need to invest in massive quantities of batteries for cars, factories.....


Biofuel looks green in principle but so far it hasn't delivered more energy than it consumes in fertilisers and processing. Right now we don't have enough fresh water to feed ourselves sustainably: if we increase the crop energy yield from the current 300 watts/capita to 5000, we will all die of thirst.

Fact is that unless we reduce either the population or the acceptable per capita energy use to about a tenth of the current value, it can't be done at all.   

[yor_on]

Yes Alan. It seems as the most expedient solution I can think of. And it won't cost a thing to decide to stay at one kid per person. If we just can find a balance there Earth, and us, should find it a much nicer place to be. But the church won't like it, neither will those in poor country's, relying on lots of kids (sons) to take care of them at their old age. you can also see it as a way showing how peoples immediate self interests stops them from seeing the benefits for their off spring in just a few generations.

[CliffordK]

to stay at one kid per person.... But the church won't like it,

Yes, the "good shepherds" of the Earth.  I wonder if part of the reason to encourage large families is to bolster their numbers in the church.

neither will those in poor country's, relying on lots of kids (sons) to take care of them at their old age.

I saw a special about a 3^rd world agricultural community, passing the family farm down from generation to generation. 

It was a small family farm, but each generation it was divided by a factor of 4 or so...    Say 16 acres down to 4 down to 1 acre per person.  Pretty soon there was nothing left to support the children, let alone the parents.

[Peter Steadman]

Scary stuff! It's a good argument for GM food. Because we are beating natural selection as a species with medical science miracles, and such forth (always wanted to use 'such forth' in a sentence lol). We will reach a point when ether, we all suffer from lack of food and water. Or, the death of the 'weak', people surplus to demand would happen by human deceleration in order to achieve a life without suffering. Makes fox-hunting look like a storm in a teacup, the rich and powerful will be Chav hunting, lol.

Saying that, if our thrust for wireless tech continues, most people would probably become sterile avoiding the problem. lol

[evan_au]

It turns out that lasers can beam power from space.

At around $4,000 to $10,000 per kilogram launched into low-Earth orbit, orbiting solar farms are far more expensive than solar cells on your roof.

If you put solar cells into low-earth orbit, they will spend about 50% of the time in darkness (like the ones on your roof). They will also spend much of the daylight hours out of sight of a ground-based receiver station.

If you put them in geosynchronous orbit (much more expensive), they will always be above a receiving station, and are only in darkness for a few hours every year, near local midnight. It means that the transmitter and receiver must be much larger for efficient power transfer.

If ground-based solar power is used to supplement other power sources during daylight hours, we probably need a change in our conventional grid to allow power to efficiently feed back into the grid. This will require local distribution transformers to have variable "taps", so that the turns ratio can be changed dynamically, allowing power to flow from homes into the grid during sunny days, and from the grid into homes at night, while maintaining a stable supply voltage.

[CliffordK]

The power transfer from geostationary orbit (22,000 miles) is likely just about as efficient as low earth orbit (500 miles or so), although there would be some loss if one is transferring from the equator to a northern latitude which would require going through more atmosphere.  And, of course, clouds may be a problem for many different light wavelengths.  Nonetheless, a large space based solar collector may be cost prohibitive. 

As far as home power installations, Most transformers can essentially be used bidirectionally, and many meters may also be inherently bidirectional, so technically it shouldn't be a problem back-feeding into the grid.  In the USA, power companies are required by law to buy back power from small power generators, although not necessarily at retail prices.  Peak power usage may also be during daylight hours, so solar power may favorably augment the grid.  However, existing power generators may not be designed to deal with multiple alternative power sources being added to the grid.  And, many alternative energy sources can drop from 100% to 0% quite frequently on a cloudy windless day, thus the grid must be designed with enough redundancy to absorb the variability of the alternative power.