Price of Milk

[joshuatree]

Re: Price of Milk

Wow, can't believe I missed this discussion. I was back reading and came across it. I was away for a few days. Right now I have to go somewhere so I'll have to get back to it later tonight. This one is right up my alley. If not for anything else, what an excellent example for my students. I'm always looking for "real world" applications to the theory. By tomorrow, I'll have the math done!

Looking forward to it. Glad to see others interested in alternative forms of power.

As for biodiesel, I dunno. If we're going to be driving Japanese micro cars, we'll have to lay off on fried food. That could mean a shortage of used cooking oil. Better to utilize what agricultural resources we're normally known for: sugar cane and pineapple.

Random, what if the micro car was fitted to sit one person, steering wheel in the middle, like a F1 race car instead? Then the micro car is still small on the exterior dimensions but ample room for the interior. Would that appeal to you then? I know one can say, then why not just get a motorcycle but not everyone is proficient, or has the courage, or wants to brave the elements.

Everyday, one can see so many single occupant work commuters on the freeways. If all these people simply used micro cars, the gridlock issue would be alleviated significantly, no doubt in my mind as maybe 2 or 3 micro cars take the same space of 1 suburban.

[acousticlady]

Re: Price of Milk

http://www.oceanpd.com/default.html

It is anticipated that future `wave farm' projects would consist of an arrangement of interlinked multi-machines connected to shore by a single subsea cable. A typical 30MW installation would occupy a square kilometre of ocean and provide sufficient electricity for 20,000 homes. Twenty of these farms could power a city such as Edinburgh.

All right, for today's lesson - I know you've all been waiting for this with bated breath and nothing else to worry about- Here's my explaination of how this works. And notice..... no math (just for our non-techies)! I'm assuming no knowledge of this so for some this may seem elementary.

It is really just a simple case of conservation of energy. The official definition of this is "Energy cannot be created or destroyed, simply transformed from one kind to another." In this case, we are transforming physical energy from the ocean wave to electrical energy. All waves have the same properties. They all have a frequency (or wavelength) and an ampltude. The actual definition of a wave is "A mechanism to transport energy from one point in space to another point in space with no net movement of the mechanism itself." What makes one wave different from another is the mechanism used to transport the energy. Ocean waves, seismic waves and sound waves are examples of physical waves. Physical particles (water, earth, air) vibrate up and down, transferring it's energy to the particle next to it and that one tranfers its energy to the next and so on. Electrical energy uses the movement of electrons in a wire or cable.

We all know the ocean waves have energy. I'm sure we've all been knocked over by the force of a wave at one time or another. The larger the wave, the more force or energy it has. The size of the wave is it's amplitude. How often the waves come in is it's frequency (i.e., how many waves per second). During the storm, the frequency is greatly increased getting one wave after another - making surfing more difficult, but on average the frequency remains fairly consistant. I'm going to appeal to the surfers here - when you are waiting for a good wave to come along and you sit there bobbing up and down, you are acting the same way as one of the water particles (no net movement from one point to another).

OK - the amount of energy is dependent purely on it's frequency and amplitude. So a whole lot of little waves can have the same amount of energy available as only a few large waves. We can't really measure the total energy, but we can measure the amount of energy per second hitting a specific area (the intensity). This is where they get the 30 megawatts over a square kilometer. A watt is the power or energy per second. When that is measured over a square kilometer, it is the intensity. When we look at it mathematically, it is proportional to the frequency squared and the amplitude squared. So the amount of energy available in a 2 foot wave is 4 times as much as in a 1 foot wave. This becomes important when we transform it into electrical energy.

Now, electricity is simply the motion of electrons within a wire. If the the electrons move in one direction, it is direct current (DC). This is what your batteries supply. But, if the electrons move back and forth it is called AC (alternating current). This is what you get out of your sockets. When it comes to running your lights or appliances it doesn't make a difference which you use. However, AC is much easier to make. When the electrons move back and forth, it is an electrical energy wave. How far back and forth they move from it's original position is it's amplitude and how quickly the move back and forth is its frequency. The easiest way to do this is to move a magnet back and forth through a coil of wire (there is an intricate connection between magnets and electricity - another lesson ) The electrons react exactly to the magnet's speed in and out. Moving the magnet in quickly forces the electrons to move far from their original position - large amplitude. How often the magnet moves through dictates the electrons frequency. The intensity of the electrical energy is only proportional to its amplitude and frequency ( a 2 foot wave is only 2X and strong as a 1 foot wave).

To transform the ocean's energy into electricity, the waves hit the "machines" which causes the magnet to move through the coil which causes the electrons to move. The coil is connected to the cable extending to land and voila (or is it viola?) we have electricity. And, because the amount of energy in an ocean wave is dependant on the square of the freq. and amp., it takes a lot less ocean energy to make the 30 Megewatts advertised.

Ok, probably more info than you needed - but school starts in a couple of weeks and its good practice for me!

[joshuatree]

Re: Price of Milk

A detailed explanation indeed, I'm no expert in the field so I can't say if you left out any details but sounds right to me. So, do you think this application will work for our islands?

[acousticlady]

Re: Price of Milk

A detailed explanation indeed, I'm no expert in the field so I can't say if you left out any details but sounds right to me. So, do you think this application will work for our islands?

Yes, I think of all the alternatives this one has the most promise. Even during the summer, when the swells are small, the amount of energy that could be generated should be more than enough. Especially on the outer islands where the number of wave machines would be much less. But even on Oahu. They may need a few more than is being used in Edinburgh.

Asthetically it shouldn't be a problem as they could be placed out of site. They could also be placed outside of the whales primary sites. Theoretically they could be placed as far out as we want. Just need a longer cable. But the longer th cable the more we need to worry about energy loss through the lines. Much as we do now, transformers may be needed to help boost the power in transit.

[GeckoGeek]

Re: Price of Milk

Much as we do now, transformers may be needed to help boost the power in transit.

Uhhhhh, transformers don't boost power. They may well be needed at both ends to minimize the power lost.

I still wonder how reliable the power output would be, both short and long term. How hard is it to accurately forecast how much power is available? Because that's going to translate into how much energy will be spent in keeping convectional generators in stand-by.

Then there's the whole "politics of 'no'" and what it's going to do to the surf. Surf doesn't come from one direction, so I'm not sure is there's a place it can be put that would assure everyone that it won't affect surfing.

[acousticlady]

Re: Price of Milk

Uhhhhh, transformers don't boost power. They may well be needed at both ends to minimize the power lost.

Duhhhh - you got me. Power in = power out. Wording issue. 10 points off for me Nothing like doing exactly what I preach not to do.....

As far as the issues surrounding this, I'd love the opportunity to investigate it further. Somehow I think the effect on surfing would be minimal. And I still think that given the other alternatives, this one has promise.

But you are right. The politics of NO will be the biggest issue. Always is.

[Pua'i Mana'o]

Re: Price of Milk

But you are right. The politics of NO will be the biggest issue. Always is.

*rubs throbbing temples*

[GeckoGeek]

Re: Price of Milk

The politics of NO will be the biggest issue.

And that's why we need to quantify the effects right up front. How much will it affect surf? Will it affect the whales? Any other marine life?

[acousticlady]

Re: Price of Milk

And that's why we need to quantify the effects right up front. How much will it affect surf? Will it affect the whales? Any other marine life?

yup - research needs to be done first - no doubt about it. Getting in touch with the group in the UK would be a good start. Getting researchers at UH involved is another. Again, I think the affect on the surf is the least of the problems. One solution (and this is off the top of my head) would be to place them where we want to reduce the surf such as near harbors. We use jettys now to reduce the surf in those areas. No matter what, the affect to the surf would only be just beyond the machines themselves. One property of waves is that they wrap around any obsticle. So theoretically, the wave height would return to normal a relatively short distance beyond the machines. No, I don't have the exact numbers but the effect would diminish as 1/r^2 (inverse square law).

I think the bigger question would be to marine life. I certainly wouldn't want to see these machines in the path of the whales or over top of coral reefs. But that is one big ocean out there. Lots of space and lots of energy.

[GeckoGeek]

Re: Price of Milk

I think the affect on the surf is the least of the problems.

I guess it depends on how you rank the problems. I'm thinking in terms of public perception of what the impact will be. I'll bet it ranks #1 or #2.

[acousticlady]

Re: Price of Milk

I guess it depends on how you rank the problems. I'm thinking in terms of public perception of what the impact will be. I'll bet it ranks #1 or #2.

Speaking hypothetically here, let's pretend we are going to present this to the public. Wouldn't we want to dash those fears right up front? I can easily imagine presenting the idea on tv. Then we could show a demonstration that proves the wave problem would be minimal. This could be done with a classroom wave demo. Very cool toy!

[joshuatree]

Re: Price of Milk

Speaking hypothetically here, let's pretend we are going to present this to the public. Wouldn't we want to dash those fears right up front? I can easily imagine presenting the idea on tv. Then we could show a demonstration that proves the wave problem would be minimal. This could be done with a classroom wave demo. Very cool toy!

With all the talk about alternative power from the governor, it be nice to see the state fund a trial unit just like they are doing in Europe. That will demonstrate the effectiveness of the concept and the tolerance/acceptance factor from the public. The power generated can always be sold to HECO.

[acousticlady]

Re: Price of Milk

With all the talk about alternative power from the governor, it be nice to see the state fund a trial unit just like they are doing in Europe. That will demonstrate the effectiveness of the concept and the tolerance/acceptance factor from the public. The power generated can always be sold to HECO.

It would. Do you or anyone have any idea how to go about it? I'm good at the details of the thing and I think I could get a few profs on board at UH (I think....) but what to do next?????? I don't even know where the governor lives

[joshuatree]

Re: Price of Milk

It would. Do you or anyone have any idea how to go about it? I'm good at the details of the thing and I think I could get a few profs on board at UH (I think....) but what to do next?????? I don't even know where the governor lives

Your guess is as good as mine. An email to the gov? Wonder how far that will go......

[Miulang]

Re: Price of Milk

It would. Do you or anyone have any idea how to go about it? I'm good at the details of the thing and I think I could get a few profs on board at UH (I think....) but what to do next?????? I don't even know where the governor lives

Acousticlady: Try looking over here...you know the Maui Research and Technology Center in Kihei? Well, they do some incubation of promising projects there. You might also be able to qualify for some State funding. You have several things going for you, not the least of which is that you're a minority (woman). I'm on their mailing list and somehow also got on their venture capital mailing list, too. Good luck.

Miulang