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Topic Title: What is the relationship between Water and Energy?
Topic Summary: Everything in terms of Human Engineering and Economics
Created On: 06 July 2013 06:10 PM
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 06 July 2013 06:10 PM
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jarathoon

Posts: 1040
Joined: 05 September 2004

If your one of those people waiting for esoteric theories of physical science to solve our energy problems, then forget it.

Confining yourself to just thinking like a physicist, creating a "Theory of Everything" so called, and then expecting to be able to solve the worlds problems, is like cutting of one leg and then expecting to walk.

To see this you have to think how a physicist would answer the question:

What is the relationship between Water and Energy?

and then compare it with how an engineer or economist or desert bedouin would answer the same question. (Actually the differences here are more intellectually important for humanity, than the difference in approach between the engineer and the physicist)

I am not going to answer this question, just use it to introduce an article in the guardian that will help you think on it...

"Global food supply under threat as water wells dry up, analyst warns"

http://www.guardian.co.uk/glob...at-water-wells-dry-up

Technocratic leadership has arrived in more and more democratic countries as the existing policital systems and political elites fail to meet the challenges we are facing. These problems are real and cannot be solved using political rhetoric alone.

All our democracies will come under pressure during the next decade or two. Temporary periods of technocratic administration may become more common, as very very difficult political decisions and complex judgments need to be made. Given our levels of debt this may happen to the UK just as it has happened in Greece, Italy and now Egypt.

All countries need to address engineering problems related to energy and water, and companies investing to help middle east countires like Egypt transparently and honestly get to grips with their critical engineering problems will find good business elsewhere as well.

James Arathoon

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James Arathoon
 08 July 2013 03:18 PM
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jarathoon

Posts: 1040
Joined: 05 September 2004

Almost a literal example perhaps is this story from a year back...

"Qatar to build innovative desert greenhouse inspired by camel's nostrils"

http://dohanews.co/post/186013...ired-by#ixzz2YSf43h7q

More metaphical thoughts are possible as well.

Another good question for a student project arises out of this:

Greenhouse technologies: what are the changes needed to move the technology from cold moist climates to hot dry climates? Or indeed from Cold dry climates to hot humid climates?

Some thoughts in regards to hot dry climates:

In a hot dry climate you want to let light radiation into the greenhouse, whilst keeping a high proportion of the heat radiation. If you want to allow only a proportion of light radiation then you have to think of a cheap and reliable way of doing this.

Is it possible to create glass with a variable silvering. Perhaps two panes of half silvered glass that can move relative to one another to push the effective silvering to 80 or 90% under control or multi-paned louvred mirrored glass.

Can you efficiently and cheaply capture the light rejected by the greenhouse control system using solar mirror collectors and solar Photovoltaic panels? Perhaps photovoltaics are too expensive to start with and a better way of using the reject heat is to direct it towards sea-water evaporators?

How do you cheaply control the humidty in a desert greenhouse using low tech designs? What would be the benefit of using slightly higher-tech designs?

Should the greenhouses be underground or under a insulating layer of sand (i.e. to avoid the process of turning sand into glass) ? The mirrors being used as light pipes to light the underground crop beds.

Ideas. More Ideas.. And still more strange Ideas... and eventually some important, practical and economic ideas and technologies might emerge...

James Arathoon

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James Arathoon
 09 July 2013 02:03 AM
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jarathoon

Posts: 1040
Joined: 05 September 2004

I suppose at the most simplistic level of analysis there are two extreme limiting states:

1. the water limited state
2. the energy limited state.

From a BBC Newsnight tv package from Egypt tonight, one immediate problem for many farmers is that although they have sufficient water from the Nile, they either can't get access to or cannot afford to pay for diesel fuel to run water pumps for long enough to irrigate their land properly. (Diesel fuel is also need for tractors)

So with this extra bit of information some obvious questions are:

1. Is it possible to alter the agricultural system so that it uses much less water?
(Probably not realistic question to focus on in the very short term)

2. Are there other ways of powering a water pump without using so much diesel fuel? e.g. a solar raised steam powered pump, waste bio-gas powered pump, a PV solar powered pump or a wind powered pump etc., Who will provide the loans to pay for new capital equipment that uses less diesel to irrigate fields? Who will train up young people to, if not build such equipment, to certainly maintain such equipment?

3. As an alternative medium term approach, are hybrid systems of agriculture possible that allow some farm diesel bio-fuel to be grown in a high yielding and compact desert "greenhouse" system, whilst using cheaper conventional irrigated agriculture methods for the bullk of staple food crops? Who is available to think about new hybrid systems of agriculture suitable for North African and Middle Eastern Climates?

I accept bringing in agricultural systems that include sea-water distilling evaporators would need a desert "greenhouse" system that was very very frugal in its water usage. If you take the right road perhaps you can end up with economically viable systems in this regard for some high value food crops or where appropriate bio-fuel crops.

I did meet someone doing renewable energy research in Egypt in 2011, but very little in the way of research funds. So if anyone has any good ideas about how to study the complex engineering and economic relationship between energy and water, that needs little or no money, but assumes a climate with plenty of sunshine, please add your thoughts....

Thanks

James Arathoon

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James Arathoon
 12 July 2013 10:50 AM
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sandip

Posts: 21
Joined: 31 March 2013

If we stick to the basic then water is one of the sources of energy like hydraulik power generated through turbine using water etc.
 12 July 2013 01:32 PM
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ectophile

Posts: 540
Joined: 17 September 2001

Originally posted by: jarathoon

Almost a literal example perhaps is this story from a year back...



"Qatar to build innovative desert greenhouse inspired by camel's nostrils"



http://dohanews.co/post/186013...y#ixzz2YSf43h7q



More metaphical thoughts are possible as well.



Another good question for a student project arises out of this:



Greenhouse technologies: what are the changes needed to move the technology from cold moist climates to hot dry climates? Or indeed from Cold dry climates to hot humid climates?



Some thoughts in regards to hot dry climates:



In a hot dry climate you want to let light radiation into the greenhouse, whilst keeping a high proportion of the heat radiation. If you want to allow only a proportion of light radiation then you have to think of a cheap and reliable way of doing this.



Is it possible to create glass with a variable silvering. Perhaps two panes of half silvered glass that can move relative to one another to push the effective silvering to 80 or 90% under control or multi-paned louvred mirrored glass.



Can you efficiently and cheaply capture the light rejected by the greenhouse control system using solar mirror collectors and solar Photovoltaic panels? Perhaps photovoltaics are too expensive to start with and a better way of using the reject heat is to direct it towards sea-water evaporators?



How do you cheaply control the humidty in a desert greenhouse using low tech designs? What would be the benefit of using slightly higher-tech designs?



Should the greenhouses be underground or under a insulating layer of sand (i.e. to avoid the process of turning sand into glass) ? The mirrors being used as light pipes to light the underground crop beds.



Ideas. More Ideas.. And still more strange Ideas... and eventually some important, practical and economic ideas and technologies might emerge...



James Arathoon



I think you're over-complicating things.

If you want to adjust the amount of light entering your greenhouse, fit blinds and employ somebody to wind the blinds up and down as required.

Similarly, to control the humidity, put windows in. Deserts tend to be very dry, so if you want to lower the humidity, just open the windows. If you want to raise it, close the windows and turn on the sprinklers.

Paying somebody a few dollars a day to look after the greenhouse is bound to end up cheaper than some high-tech solution that will only keep breaking down.

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S P Barker BSc PhD MIET
 12 July 2013 02:00 PM
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jarathoon

Posts: 1040
Joined: 05 September 2004

Originally posted by: sandip

If we stick to the basic then water is one of the sources of energy like hydraulik power generated through turbine using water etc.


Why stick to the just the basic?

It seems to me that maintaining resilient and sustainable farming systems (with economically competitive outputs) in the face of long term environmental change and short term environmental variability amongst other things, is a complex and important set of problems that students should not be afraid to think about, at the same time as finding a way to fix or improve a failed water pump or turbine...

If a pump or turbine becomes too expensive to maintain or operate, you may have to rethink the whole system....

For example if a diesel pump that pumps so many litres per second and which is critical to maintianing irrigation of farmland becomes too expensive to run, what solutions do you as a consulting engineer suggest.

Would it be more better to set aside some land for growing crops to make biodiesel for the pump or instead build a solar microgrid with solar PV panels, appropriately sized battery and an electrical pump or instead generate biogas from farm waste and run a methane powered pump?

I suppose it depends on the extent to which the pumping has to be done at night (and thus the associated amount energy storage required), the relative capital costs of change, the cost of labour vs capital, the farmers income and ability to fund new capital spending and also what local skills are available locally to support and maintain the new systems long term.

If the farmer says to you that none of the solutions above are economically viable, then even wider systems thinking may be required in terms of organising farms into co-operatives etc. Where for example one farmer specialises in producing biodiesel or biogas for running irrigation pumps and the others concentrate on producing food.

Another example might be if farmers can no longer afford fertilizer. Who is best placed to devise the best crop rotation techniques (involving nitrogen fixing plants somehow) and how the new outputs then created are best used to improve soils, feed animals or produce biogas etc.

James Arathoon

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James Arathoon
 12 July 2013 02:18 PM
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jarathoon

Posts: 1040
Joined: 05 September 2004

ectophile

"Paying somebody a few dollars a day to look after the greenhouse is bound to end up cheaper than some high-tech solution that will only keep breaking down."

You may still need a way of measuring temperature and humidity reliably (however low tech the method) to then draw attention to the fact that a particular action is needed to stop plants either cooking or drying out....

If the farm worker is to judge this for themselves, what happens if they fall asleep. In this regard it might be easier to design and engineer simple fail safe mechanisms that protect the plants at the extremes, rather than going to the expense of fully comprehensive humidity and temperature control system; this is especially so if adustments to the ventilation and shading systems don't need to be that accurate and only need to be made every few hours or so...

James Arathoon

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James Arathoon
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