Wind power has emerged as a viable renewable energy source in recent years — one that proponents say could lessen the threat of global warming. Although the American Wind Energy Association estimates that only about 2 percent of U.S. electricity is currently generated from wind turbines, the U.S. Department of Energy has said that wind power could account for a fifth of the nation’s electricity supply by 2030.

But a new MIT analysis may serve to temper enthusiasm about wind power, at least at very large scales. Ron Prinn, TEPCO Professor of Atmospheric Science, and principal research scientist Chien Wang of the Department of Earth, Atmospheric and Planetary Sciences, used a climate model to analyze the effects of millions of wind turbines that would need to be installed across vast stretches of land and ocean to generate wind power on a global scale. Such a massive deployment could indeed impact the climate, they found, though not necessarily with the desired outcome.

In a paper published online Feb. 22 in Atmospheric Chemistry and Physics, Wang and Prinn suggest that using wind turbines to meet 10 percent of global energy demand in 2100 could cause temperatures to rise by one degree Celsius in the regions on land where the wind farms are installed, including a smaller increase in areas beyond those regions. Their analysis indicates the opposite result for wind turbines installed in water: a drop in temperatures by one degree Celsius over those regions. The researchers also suggest that the intermittency of wind power could require significant and costly backup options, such as natural gas-fired power plants.

Prinn cautioned against interpreting the study as an argument against wind power, urging that it be used to guide future research that explores the downsides of large-scale wind power before significant resources are invested to build vast wind farms. “We’re not pessimistic about wind,” he said. “We haven’t absolutely proven this effect, and we’d rather see that people do further research.”

Daniel Kirk-Davidoff, a chief scientist for MDA Federal Inc., which develops remote sensing technologies, and adjunct professor of meteorology at the University of Maryland, has examined the climate impacts of large-scale wind farms in previous studies. To him, the most promising result of the MIT analysis is that it indicates that the large-scale installation of wind turbines doesn’t appear to slow wind flow so much that it would be impossible to generate a desirable amount of energy. “When you put the wind turbines in, they are generating the kind of power you’d hope for,” he said.

Tapping the wind resource

Previous studies have predicted that annual world energy demand will increase from 14 terawatts (trillion watts) in 2002 to 44 terawatts by 2100. In their analysis, Prinn and Wang focus on the impact of using wind turbines to generate five terawatts of electric power.

Using a climate model developed by the U.S. National Center for Atmospheric Research, the researchers simulated the aerodynamic effects of large-scale wind farms — located both on land and on the ocean — to analyze how the atmosphere, ocean and land would respond over a 60-year span.

For the land analysis, they simulated the effects of wind farms by using data about how objects similar to turbines, such as undulating hills and clumps of trees, affect surface “roughness,” or friction that can disturb wind flow. After adding this data to the model, the researchers observed that the surface air temperature over the wind farm regions increased by about one degree Celsius, which averages out to an increase of .15 degrees Celsius over the entire global surface.

According to Prinn and Wang, this temperature increase occurs because the wind turbines affect two processes that play critical roles in determining surface temperature and atmospheric circulation: vertical turbulent motion and horizontal heat transport. Turbulent motion refers to the process by which heat and moisture are transferred from the land or ocean surface to the lower atmosphere. Horizontal heat transport is the process by which steady large-scale winds transport excessive heat away from warm regions, generally in a horizontal direction, and redistribute it to cooler regions. This process is critical for large-scale heat redistribution, whereas the effects of turbulent motion are generally more localized.

In the analysis, the wind turbines on land reduced wind speed, particularly on the downwind side of the wind farms, which reduced the strength of the turbulent motion and horizontal heat transport processes that move heat away from the Earth’s surface. This resulted in less heat being transported to the upper parts of the atmosphere, as well as to other regions farther away from the wind farms. The effect is similar to being at the beach on a windy summer day: If the wind weakened or disappeared, it would get warmer.

In contrast, when examining ocean-based wind farms, Prinn and Wang found that wind turbines cooled the surface by more than one degree Celsius. They said that these results are unreliable, however, because in their analysis, they modeled the effects of wind turbines by introducing surface friction in the form of large artificial waves. But they acknowledge that this is not an accurate comparison, meaning that a better way of simulating marine-based wind turbines must be developed before reliable conclusions can be made.

In addition to changes in temperatures and surface heat fluxes, they also observed changes in large-scale precipitation, particularly at the mid-latitudes in the Northern Hemisphere. Although these changes exceeded 10 percent in some areas, the global total changes were not very large, according to Prinn and Wang.

To investigate the effect of wind variability on the intermittency in wind power generation, the researchers used the climate model to estimate the monthly-mean wind power consumption and electrical generation for each continent, concluding that there are very large and geographically extensive seasonal variations, particularly over North and South America, Africa and the Middle East. They explain that this unreliability means that an electrical generation system with greatly increased use of wind turbines would still require backup generation even if continental-scale power lines enabled electrical transmission from windy to non-windy areas.

Although Prinn and Wang believe their results for the land-based wind farms are robust, Wang called their analysis a “proof-of-concept” study that requires additional theoretical and modeling work, as well as field experiments for complete verification.

Their next step is to address how to simulate ocean-based wind farms more accurately. They plan to collaborate with aeronautical engineers to develop parameters for the climate model that will allow them to simulate turbines in coastal waters.

A new study shows that people are more likely to cheat and steal after buying green products.

TOMS Shoes has announced their third annual One Day Without Shoes campaign for Apr...Read the full story on TreeHugger

A female whale trainer died this afternoon at SeaWorld’s Shamu Stadium in Orlando, Florida, with witnesses saying she was killed during a public "Killer Whale" show.

According to the Orlando Sentinel, a local TV station is reporting that a female employee was killed after she was grabbed by one of the theme park's whales at the start of a public show.

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Last night I realized I was whining too much in this blog about products that don't work. So I decided to write today's post about a product that exceeded my expectations. We designed our home with a residential elevator. We didn't want to go through all the effort of building our dream home and then decades from now need to move when stairs become an issue. I was worried about having an elevator because it seems like exactly the sort of thing that will break on a regular basis. Last night I realized my negative expectations had been wrong. I need to lighten up. That elevator has worked like a charm, and we use it all the time for moving heavy objects up and down stairs.

So, as I'm walking across the living room last night, composing in my mind today's post in praise of the elevator, Shelly tells me the elevator is broken. And so it is. I'll have to call someone about that today. So I changed my plan and decided to write about my broken elevator instead. (Every word of that is true, by the way. I was literally composing the elevator praise post in my head when it broke.)

This morning I woke up at 6 AM and walked the dog as usual. I should mention that we designed the house with an automatic dog door, which functions as advertised, except it scares the bejeezus out of little Snickers and causes her to poop in the kids' rooms. So I walk her instead. In the rain.

After the dog does her business, I visit our spiffy new coffee maker. It's terrific. I push one button and it grinds the beans, mixes it with fresh water (it's plumbed!) and produces a steaming cup of excellent java. Except lately it has only been spitting out something like brown dishwater, which I drink anyway, for the placebo effect. Today I decided to take action. So after half an hour with the manual, I corrected a setting that had somehow unraveled itself, as if by ghosts. (Yes, the coffeemaker has a setting that allows you to create brown dishwater instead of something more like coffee. I'm not clear why.)

Coffee in hand, I go to my computer to start writing. But my computer decided to reboot itself last night, against my will, for some sort of Windows update. And it locked up. So I do a hard boot. And wait. And wait. And wait, while the creative juices slowly drain from my body. Once rebooted, I try to start Firefox. And I wait, and I wait. I like to check the comments on my daily strip before I do anything else. Great, I see that my Canadian stalker is back in full force, leaving crazy comments, driving out the normals. She's been cyberstalking me for about seven years now, off and on, whenever she goes off meds. She likes to call anyone I do business with and tell them I've been sexually harassing her, sending goons to search her home, bugging her phone, and my favorite: using my comic strip as a way to send secret messages to her. The police can't help me because she's Canadian. We block her IP address on a regular basis, but she keeps changing machines.

Anyway, seven years is enough. I'm in a bad mood. So as of today, I'm declaring her my mascot. Yes, stalker, this time I am talking directly to you. For the first time, it's not the voices in your head. Leave some good crazy comments that we can all enjoy.

My strategy is to get you so wound up that your husband, if you still have one, puts you back on your meds. Nothing else has worked. Let's try this.

A new campaign that plays off a pornographic stereotype has gotten more attention than even its creators intended.

I've run into this situation twice in the past year: A sales person will tell me, in insincere confidence, what a jerk some other customer is. It usually comes in the form of a story that is presumably meant to amuse me, as in "You won't believe what this customer did the other day." There's usually a point to the story, such as Don't waste a sales person's time if you aren't going to spend a lot of money. Or Don't ask stupid questions. I suppose the sales person who shares these stories wants me to think he's bonding with me. But all I feel is a desire to beat him to death with whatever he's selling, while yelling "If you don't want people buying inexpensive items, why do you carry them in your f%&@ing store???"

And after he's dead, I might keep beating him while yelling something along the lines of "If your products weren't so f@&#ing confusing, maybe people wouldn't have to ask so many questions!"

On another topic, I believe there is a special place in Hell for companies that make consumer electronics with black buttons on black faceplates, especially when those products are generally used in low light situations. Is that even trying?

Let's talk about thermostats. How many people know how to program their thermostats? My guess is 30% of the public. In my last home, the interface was so random that at least half of the time we simply gave up trying to set the temperature and assumed "Something must be broken." Imagine how much energy could be saved with a little work on thermostat interfaces. The market system doesn't work with thermostats because they generally come with the house. And if you shopped for them in the store, you wouldn't get a full sense of how easy they are to use. Maybe there should be a law that says if 75% of consumers can't set the thermostat in controlled tests then those products aren't allowed on the market.

We use retractable leashes when walking our dog. The good versions of this product have a handle grip and a thumb control for stopping the leash from retracting. If you need to reel your dog in, you pull the handle while pressing the button. It's a very nice design. Recently we got one that changes things up. If your dog starts running into traffic, you have to pull on the handle while releasing your hold on the retraction button. That's right - you have to squeeze some muscles in your hand while releasing others. Try that at home. Squeeze your thumb and your index finger together while relaxing your pinky. You can do it, if you get in the lotus position and burn incense, but it's not the best design if you're in panic mode and trying to keep your dog from running into traffic. I wonder if the designers ever tested the product. And if they did, how many dogs died?

For a class project, nine mechanical engineering students at Yale devised a working bicycle with a hubless wheel. It's suspension-free and they only had the time and resources to go hubless on one wheel, but it works:

Why do it? As one of the students explains,

First, it looks cool. Second, we only had a semester so we wanted to pick something that was both feasible and challenging. Also, you can do a lot of things with the space that opens up where the spokes use to be. You can stick an electric motor in there. You can install some sort of gyro balanced storage basket. Finally, the fact that we couldn't find pictures of a real spokeless bicycle online really sealed the deal.

via reddit

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Clay Buchholz has a problem many people wish they had: He can’t gain weight.