Day to Day Green
Rechargeable Battery Comparison Summary From Engaget 
Wednesday, May 12, 2010, 11:51 AM
Posted by Administrator



You can read the whole article and its references by following the related link below. However, this is the outcome.

If you are in the market for rechargeable batteries, there is very little difference in performance. The life of the batteries is claimed to be 2x by one manufacturer but the article did not have a long run test to verify they would outlast competitors by that amount. By the way, that is the number of recharge cycles, not how many hours they will run a device.

Average prices:

PowerGenix Batteries: $11
PowerGenix Charger Bundle: $23

Energizer Batteries: $12
Energizer Charger Bundle: $20

Eneloop Batteries: $10
Eneloop Charger Bundle: $21

As the article said, a safe bet is whichever is on special.

Bladeless wind turbine to generate up to 10KW of power ???? 
Wednesday, May 5, 2010, 02:08 PM
Posted by Administrator



From the article:
_____________________________________________
Solar Aero has recently been awarded a patent for a new bladeless wind turbine, the Fuller Wind Turbine, which is being claimed to be entirely safe for wildlife and as an added advantage, it generates electricity without any noise.

The entire assembly is contained in the housing and the only movement visible to an observer is the movement of the housing as it adjusts to the direction of the wind. The company expects that their wind turbine will be able to deliver power at a comparable cost to coal-fired power plants.
_____________________________________________

This is not a lot of information. First, we measure energy in use over time, so the statement of 10KW in the heading is without supporting information. Does the 10KW come from the portable size unit shown in the picture or a unit that is 50x larger? Does the 10KW come as a monthly value since our utility bills come monthly? These are questions I am curious about.

What I can tell you with some certainty is this, a class 1 air flow contains about 200 watts per square meter. This means; If your machine can catch 1 square meter of air in a class 1 flow, 100% efficiency would mean collecting 200 watts of energy. Classes range from Class 1 (200 watts/square meter or less at 50 meters altitude) to Class 7 (800 to 2000 watts/square meter). However, there are problems with this possibility I will address in a minute. Take a look at that photo, lets assume the opening is about 1 square meter. This means the maximum, in a theoretical perfect world, that this machine can harvest is 200 watts in a class 1 air flow.

Now the problem: There is a little piece of bad news called Betz' law. Back in 1919 a smart German physicist named Albert Betz figured out that the most you can possibly get out of a wind turbine is around 59% of the power in the wind. This is a nondisputable bit of physics. I'm not going to prove it here but it is not hard to at least understand why we can never convert 100% of the wind's power.

Imagine a wind energy extraction machine of 100% efficiency that could take all of the kinetic, (moving), energy out of the wind. That would mean the velocity, (movement), on the "out" or "leaving" or "exit" side of the turbine blades would be zero, zilch, nada. No kinetic energy left. No velocity left. No wind. Dead calm.

If the velocity leaving the blades is zero then the air wouldn't be leaving at all. There would be no air movement, meaning the air after the blades isn't getting out of the way of the air coming in, which would mean the fresh air couldn't come in, which would mean there is no air flowing through the turbine blades, which would mean no power. In order to at least keep the wind moving through the turbine there has to be some velocity or energy in the air after going through the blades so that the air can get out of the way of the air coming through next. Sort of a "Catch-22". Just to keep the machine running at all the efficiency has to be less than 100%.

Mr. Betz pointed this out and then proceeded to prove, with solid physics and math, that the best that could be achieved by a wind turbine is around 59%. In other words, a perfect best-possible wind turbine would be able to convert almost 59% of the power in the wind into mechanical rotating power.

With this in mind, take another look at that photo. The idea is nice, the execution is elegant, however the promise is very big compared to known processes.

Consider also, this machine needs to be aligned with the wind to function. In areas that the wind changes direction, there will have to be another device or feature to keep the alignment.

This type of turbine will spin very fast, but there is also no torque for doing work. If you are interested, here are some further references on the Tesla turbine:

http://en.wikipedia.org/wiki/Tesla_turbine
http://en.wikipedia.org/wiki/Boundary_layer
http://en.wikipedia.org/wiki/Reynolds_number
http://en.wikipedia.org/wiki/Wind_turbine


Solar Classrooms - This Modular Classroom Is Environmentally Friendly 
Wednesday, May 5, 2010, 01:56 PM
Posted by Administrator



American Modular Systems has unveiled the Gen7 - its line of green indoor learning environments. The Gen7 represents the state of the art in green classroom environments, offering a range of time, money and energy-saving features that provide a safe, healthy, eco-friendly, low-maintenance environment that fosters optimal learning potential.

Gen7's self-contained classroom solutions are delivered 90 percent complete and installed in as little as a few days with minimal job-site disruption.

Among the highlights of these grid-neutral classrooms are their high recycled and recyclable materials content, low and zero-VOC interiors, state-of-the-art acoustical design, energy-efficient mechanical and electrical systems, and smart lighting system with integrated daylight harvesting features. In addition, Gen7 has California Department of the State Architect approval. Piggyback-able and with PC approval, Gen7 saves time and money in the procurement process, which can take as little as 90 days from order to installation.


Flowers For Mothers Day - Get Local, Visit A Farmers Market 
Tuesday, May 4, 2010, 12:52 PM
Posted by Administrator
If you are going to buy flowers for mothers day, there is still time in many cases to get them at a local farmers market. This will help ensure they are locally grown and picked. This also helps support the local economy.

Remember, honoring mom does not mean you have get her big splashy gifts or special order flowers, the extra effort you make to be involved will be appreciated too.


Cinco De Mayo History and Celebration 
Tuesday, May 4, 2010, 12:31 PM
Posted by Administrator
The 5th of May is not Mexican Independence Day. Mexico declared its independence from mother Spain on midnight, the 15th of September, 1810. And it took 11 years before the first Spanish soldiers were forced to leave Mexico.

So, why celebrate Cinco de Mayo? Because 4,000 Mexican soldiers smashed the French and traitor Mexican army of 8,000 at Puebla, Mexico, 100 miles east of Mexico City on the morning of May 5, 1862.

As Americans, we should also celebrate this particular holiday because the French may have gained a foothold if the battle of the Mexican army had failed. Remember, at the time, the US was in a state of civil war and not in the best position to defend itself if the French army had turned our direction next.

By the way, if you are planning to go out for a Mexican Food dinner, make reservations ASAP.


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