Wind power not as safe as we think?

Now before we start taking down our turbines, we have to realize that wind turbine failure is very uncommon. I’ll make the analogy to air travel. Many people are afraid to fly even though statistically its much more dangerous to travel by car. Statistics and probability do not always correlate with public fear.

The question: Are these breakdowns the product of improperly sized turbines (i.e. NYC East River tide turbines)? Or is the occasional wind turbine failure inevitable?

-jk

http://earth2tech.com/2008/02/26/vestas-wind-turbine-explodes-with-power/

High-Altitude Wind

An article I just read mentioned this concept… its the first time i’ve heard of it. Apparently Google.org (Google’s philanthropic arm) is investing $10 million into a company (Makani Power, Inc.) with a proprietary design for harnessing high altitude wind.

The idea here is that with higher altitudes come much stronger winds.

Wind also becomes much more dependable:

The upper side of these graphs, however, seems pretty ambitious. Since the tallest building in the world is about 800m, a terrestrial building wouldn’t even make it to the first tick mark. Instead, it must be some sort of massive kite or blimp.

$10 million isn’t exactly chump change… Google must really see something concrete here. Since its proprietary, no designs are disclosed on the website. Any ideas on what they could be thinking of?

http://www.reuters.com/article/ousivMolt/idUSN0630565920080206

UPDATE:

I found a few concepts for kites that people have come up with.  Pretty cool stuff.. although pretty far from safe.

That first one has apparently been developed and tested successfully:

http://www.rense.com/general78/kinet.htm 

List of High Altitude Wind Companies/Concepts:

http://peswiki.com/index.php/Directory:High_Altitude_Wind_Power

Article on CO2 and Temp correlations

This was on the word press homepage on sat afternoon. It has an article attached:

http://wattsupwiththat.wordpress.com/2008/01/25/warming-trend-pdo-and-solar-correlate-better-than-co2/

This guy started the weather channel and shows with data that CO2 and temp changes do not correlate well (an R squared correlation of 0.44), but rather cycles in ocean, Pacific Decadel Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO) correspond much better to the temp changes. He explains how the PDO creates El Ninos and La Ninas. He gets an R squared of 0.83. I do not fully understand PDO and AMO and its driving mechanisms, so it is tough for me to readily except the relationship. He also relates temp changes to Total Solar Irradiance (TSI) and explains how changes in the sun’s “brightness” can create atmospheric temperature changes. Finally he shows that there is a negative correlation between CO2 and temp changes since in the last decade, which is when he was seen the temperatures spike the most. I do believe that correlation is not causation, but do I think discrepancy eliminates causation.

The following link was written in response to the above by some guy at U of Alabama – Huntsville. It shows CO2 solubility in water with temperature (CO2 = 0.323e^(.0316Temp))) and suggests that perhaps rising atmospheric temperature changes are driving increased CO2 concentrations, not the other way around. He uses the data at Mauna Loa, Hawaii – which is the main source of data for atmospheric temperature that guys like Al Gore discuss.

http://wattsupwiththat.wordpress.com/2008/01/25/double-whammy-friday-roy-spencer-on-how-oceans-are-driving-co2/

He very nicely explains a dip in temperatures in 1992, writing that oceanic cooling caused by a cooling of a mountain created the drop in CO2 concentrations.

I enjoyed these articles and thought I’d send them along.

From SN:

So the questions are how much CO2 stays in the air, and how much dissolves into the ocean.

If a lot of CO2 ends up in the ocean, there will be less in the air, and the effects of global warming may be reduced. If the ocean releases CO2 back to the atmosphere, the greenhouse effect may be enhanced or prolonged.
Look at the temperature and CO2 plots with temperature and CO2 data from BATS (Bermuda Atlantic Time-Series Study)

http://www.coexploration.org/bbsr/classroombats/html/tempco2plot.html

From Jkace:

As one of the few posters here who thinks there may be something to this whole global warming thing, I will be playing the role of devil’s advocate.

It looks like someone spent a lot of time trying to compare this data. While it sure looks good as finished graphs, there are a few problems. First, the graphs scale differently on the Y-axis, showing that the data fits visually much better than it does quantitatively.

Using increased solar irradiation as an explanation for our current rise in temperatures has been disproven. If the sun were acutally getting hotter, we would see an increase in temperatures more significant on the outer layers of the atmosphere. With the “greenhouse effect”, radiation pierces these layers and heats lower levels of the atmosphere. Temperature data from the outer atmosphere has actually shown a cooling over the past 100 years.

As for PDO, I believe this is an effect more than a cause. A general warming trend would lower the solubility of CO2 in the ocean, which releases additional CO2 into the atmosphere. A lot of the effects of global warming are like this (reflection of light on ice versus absorption in liquid).  These effects help explain why CO2 is at the highest level its been in the past 400,000 years (by over 20%), even though “human produced” CO2 only accounts for 5% of the carbon cycle (a popular anti-global warming talking point).

One last point… this temperature data set, while comprehensive, only looks at the continental United States. Any true statistical analysis needs to consider the entire planet. Unless we put the US into an adiabatic box.

Cooling in a drought

A story in today’s USA Today suggests problems in the south with lack of water and cooling of nukes.

http://www.usatoday.com/weather/drought/2008-01-24-drought-power_N.htm

In NJ we have a problem with cooling at the Oyster Creek plant. Two ways to use water – one is to cool directly, taking water from a source, heating it up and returning it (hopefully not hot enough to cook fish). The second is to take water and evaporate it. The second is powerful, but actually consumes the water!!! So as water becomes scarce (and warm), which is the least harmful way to cool a power plant? mrm

From M. Khan:

… a new way to cool nuclear reactors which would supposively save upto 98% of water used by existing nuclear reactors… being built in Southern Maryland – scheduled to be up and running by 2015 (joint venture between Constellation energy and a french company) – a similar hybrid cooling tower was built in West Germany back in 1988

http://www.baltimoresun.com/news/local/bal-te.md.reactor25dec25,0,4107050.story

They call it a hybrid-cooling tower… what is it exactly a hybrid of? How does it work differently than a traditional tower? It uses fans… but wouldn’t that increase the evaporation rate, as opposed to conserving it?  -jk

I was able to find a “hybrid type” cooling tower from SPX, apparently they use a heat exchanger to pull heat from the cooling water  into an air-stream, which can help curb evaporation.  -jk

http://spxcooling.com/en/library/detail/balcke-hybrid-cooling-tower/ 

 

Pressure Exchangers?

I’ve been doing some research with desalination plants and keep getting references to a “Pressure Exchanger”.  Anyone ever heard of this?  It’s like a heat exchanger, but instead of transferring heat from one stream to another it transfers pressure.  If it does in fact exist, I feel like it could have important applications outside of desalination.

Biofuel’s New Baby: Switchgrass

Credit: Image courtesy of USDA-ARS

I’ve always been skeptical about biofuel technology, mainly because its illogical to think that land and crops currently being used as food sources should be converted to ethanol production. More recent developments and findings with cellulosic crop-based fuels, however, have caught my eye.

Switchgrass has been getting more buzz recently, especially since the feasibility of corn ethanol has been called into question (negative net energy). Here’s some fun facts on the potential of switchgrass:

• Recent study showed 5 times the energy output (ethanol) to the energy input (energy needed to grow, harvest, and process the switchgrass into ethanol).
• Essentially carbon neutral — absorbs as much carbon dioxide as it emits when the ethanol is burned.
• Can be grown on farmland no longer fit for crops.

What do you guys think? Does ethanol from switchgrass stand a chance versus fuel cells, liquid coal, or electric vehicles?

jk

http://sciencenow.sciencemag.org/cgi/content/full/2008/107/1?rss=1

http://bioenergy.ornl.gov/papers/misc/switgrs.html

http://www.scitizen.com/screens/blogPage/viewBlog/sw_viewBlog.php?idTheme=14&idContribution=1377

Thanks to David Fridley for the following:

“The original article published in the Proceedings of the National Academy of Science (PNAS) was revealing, since there they have the underlying data tables. The “5 times” return is an accounting fiction: they omit completely the bioenergy used as fuel input in the ethanol plant, and credit the ethanol produced with over 5 MJ/liter of electricity sold (these are results of a model only, since no such plants actually exist). Biomass is energy, and omitting it is like saying a biomass power plant consumes no energy because it burns wood.

Cellulosic ethanol is far from carbon neutral. That could only be achieved if the feedstock could plant itself, harvest itself, transport itself, process itself, and transport itself again to your fuel tank. Otherwise, all those stages of the process will require fossil fuels.

The Achilles heel of all ethanol is both the water requirement (higher for cellulosic than starch or sugar) and the requirement of distillation and dehydration. These two steps alone consume 1/3rd of the energy in the final product, not counting anything other energy use in the chain. The high “returns” you read about from Brazilian sugarcane or in this article results from omitting the biomass energy input to the process. Thermodynamically, ethanol simply can never provide much of a net energy return.”

Here’s a link to the original paper published by the PNAS.  (Login or university connection required)

Cars running on compressed air?

It looks like an Indian car company is trying to commercialize a car that uses a compressed air engine. They claim:

• Costs about 1.50 Euros ($2.20) to refill the compressed air tank.
• Can run for 125 miles before refueling.
• Can reach speeds up to 68 MPH.

Looks pretty darn impressive.

What psi do you think would be needed in the tank to reach these levels of performance? Why isn’t this getting more hype?

From Scitizen

Credits to Dr. Muller and Greg Muller:

Safety Issues:

A 79 gallon tank at 4,400 psi. This is a LOT of potential energy to have underneath you in a high speed collision. What does the company say to skeptics?

“Compressed air tanks have already been tested safe by one of our partners EADS(AIRBUS). This company’s reputation in the aeronautical field is indisputable, and they have been proven in a thorough way the reliability of our tanks. What’s more, the compressed air does not present any risk of explosion. Countless tests have been carried out in the most extreme conditions (gun shoots, resistance to fire…) to guarantee passenger safety in every possible condition. The high pressure tanks have been developed using a similar technology as those used in natural gas vehicles and by firefighters. All are produced with carbon fiber over plastic.
The tanks that MDI puts in its vehicles are similar to those already in use in natural gas busses in Germany and also other countries.”

Believe them? I’ll let you decide for yourself. It should be noted that this car has not passed US safety standards, only European. Not sure if there is much of a difference.

Maintaining Peak Power:

A question they don’t seem to answer on their website is how the same amount of power is available when the tank is full as compared to almost empty. Since the tank’s volume is constant, the pressure will lower as the air is used in the engine. This lower pressure would result in decreased engine torque. Any ideas as to how they might be working aroung this issue?

NEW (2/13): The Hydristor

This design is being developed for both new installation in cars and retrofits. Instead of a conventional hybrid, which regenerates energy from braking into a battery, this system would store the shaft power of braking as compressed air. The device, i would assume, is essentially a compresser that can work at any load level. This design also has appeal for the grid: if compressed air ever became a realistic way of transporting energy, this device would act as the transformer to convert to appropriate power levels.

As this article suggests, if wind turbines could store their energy in large compressed air tanks instead of being converted directly into electricity, it would help mitigate the problem of inconsistent power from wind.

From:

http://pesn.com/2008/01/23/9500469_Hydristor_Pneumatic_Grid_Transmission/

jk

http://auto.howstuffworks.com/air-car1.htm

http://www.theaircar.com/tecno.html

Kyoto is useless! it’s like buying few seconds

Signed in 1997 by most of developed and developing nations except USA and Australia. Here it was decided that the industrial nations should reduce their overall CO2 emissions in the period from 2008 to 2012 by about 20% below what they would otherwise have been. The question is “Is Kyoto protocol cost effective?”.

My answer is May be Not! Even if almost all countries sign it, and all countries live up to their commitments and stick to them throughout the 21’st century (which is impossible), the change will be minuscule. The temperature by 2050 will  be an immesurable 0.1 degree F lower and even by 2100 only 0.3 degree F. lower. This means that the expected temperature increase of 4.7 degree F. will be postponed just by five years, from 2100 to 2105.

This data should be scientifically entirely uncontroversial as the five-year postponement over one hundred years is derived from work by one of IPCC’s foremost modelers.

Refer: Bohringer, C., & Vogt, C. (2003). Economic & environmental impacts of the Kyoto. Canadian journal of economics, 36(2), 475-494 for more details.

Bloomberg and Microturbines

Does someone know what happened?   For awhile microturbines were having great difficulty getting implemented because of the high the pressure gas source it needs.  Even though the gas compressor was located next to the turbines, some fire departments were ruling that special permits were needed.  Recently the Mayor of NY came out with some ruling and Capstone Microturbine has been going through the roof…. any connection???   mrm

Condensor buffers

The Swedes have a patent for a steam engine which has a unique energy storage device in the condensor.  Apparently they have a material encased in a sphere which changes phase (and stores energy) at temperatures which must about about 100 degf.  This material freezes and thaws as the temp goes up and down, thereby smoothing out changes in load.  Neat idea.  But, what material would you use to make something like this?     mrm