In my last blog, I noted that vertical axis wind turbines (VAWTs) leave much to be desired. My point was that these designs, which have been around for thousands of years, just haven’t panned out. Buyer beware: they’re not all they’re cracked up to be (See An Open Letter-To inventors of Vertical Axis Wind Turbines and Rooftop Wind 'Technology Breakthroughs'.) I wasn’t trying to discourage people from tinkering with them, but I was trying to warn folks who think they’re going to be making a wise investment from buying one.

Many of you posted comments to the contrary, either accusing me of stomping on the dreams and aspirations of young inventors or simply not knowing what I was talking about. Some readers accused me of making baseless claims without any science to back up my assertions.  Let me provide some more information on VAWTs.

While many modern VAWT inventors show videos of their turbines spinning, which convince news organizations and potential buyers of their value, it’s not spinning blades that matter. What matters is energy output. Because wind speeds are low at ground level, VAWTs won’t produce much energy — nowhere near as much useful energy as a well placed horizontal axis wind turbine. That’s why horizontal axis wind turbines are the technology of choice for most applications. 

The main reason that wind speed is so low at ground level is ground drag. Ground drag is caused by friction when air flows across a surface. Friction is the force that resists movement of one material against another.

When wind flows across land or water, friction dramatically reduces the speed with which wind flows over land.  Ground drag due to friction varies considerably, depending on the texture or roughness of the surface. The rougher or more irregular the surface, the greater friction.  As a result, air flowing across the surface of a lake encounters less friction than air flowing over a meadow. Air flowing over a meadow encounters less friction than air flowing over a forest.

Interestingly, friction slows wind speed to a height of about 1,650 feet above the Earth’s surface. However, the greatest effects are closest to ground — the first 60 feet (20 meters) above the ground over a relatively flat, smooth surface. 

The effect of friction is quite profound. A 20-mile-per-hour wind measured at 1,000 feet above the surface of the ground covered with grasses, flows at 5 miles per hour at 10 feet — where most VAWTs are located. It then increases progressively until it breaks loose from the influence of the ground drag or friction at around 80 feet.

Because the effects of friction decrease with height above the surface of the Earth, savvy installers typically mount their wind machines on towers 80 to 120 feet (24 to 37 meters). This removes them from the influence of energy-robbing ground drag. At these heights, the winds are substantially stronger than they are near the ground.

Savvy installers also avoid suburban and urban environments because the surface texture is quite rough in these areas. Trees and buildings dramatically lower annual average wind speeds. They also create a lot of turbulence and eddies — pockets of relatively dead air. Place any turbine in this environment and you can expect significantly reduced energy production.

I like the looks of a lot of VAWTs and wish inventors success, but don’t lose track of the fact that there’s very little energy in ground-level winds during a given year. In fact, a recently published study of wind turbines mounted on buildings in England showed that many turbines failed miserably when it came to energy output. Average wind speed at these levels were just too low to produce a significant amount of electricity. The inverters in many of these systems consumed more energy than the wind turbines produced in a year. See the results of the Warwick Wind Trials.

When you invest in a wind turbine, you want energy output. It’s not spinning blades, but electricity that most of us want — and lots of it — to make our investment worth the while.

Power available from the wind is a function of the wind speed cubed. If the average annual wind speed is low, which it is at ground level or even on the roofs of homes, you just won’t get much energy from a turbine — any kind of turbine. (See Rooftop Wind-Determining Your Resource.) Mounting a turbine at ground level places it in much weaker winds at most locations. It is a bit like mounting solar panels in the shade! NREL’s wind energy expert Jim Green says, “For a given swept area, VAWTs just don’t extract quite as much wind energy as a well-designed HAWT.” 

I’d be happy to be proven wrong. Show me the data that indicates that a ground-level or even a roof-top turbine of any sort produces a sizeable amount of electricity during a year!

It is important to note that years of experience with VAWTS has been rather discouraging, to say the least. “Hundreds of commercial VAWTs were installed in California in the late 1980s and early 1990s,” according to energy consultant Bob Aram. “They all failed and were removed from service. These were not experimental units, but production units.”

Ever wanted to build your own wind turbine, install your own solar panels or convert your car to electricity but never thought you could really do-it-yourself? Then think again.

Dan Chiras, one of Mother’s contributing editors and leading expert in the field of green building and renewable energy, is now hosting hands-on DIY workshops at his recently opened Evergreen Institute Center for Renewable Energy and Green Building in Gerald, Mo. Topics cover a wide range of energy efficiency solutions from passive solar heating and cooling to designing and building your own backyard wind turbine. “We won’t just tell you what’s out there, we’ll tell you where to find it and teach you how to do it” Chiras told The Missourian’s online newspaper, emissourian.

Courses range from one to six days in length, and prices start at $125 for a one-day workshop and increase to $750 for a lengthier, six-day course.

Chiras is extending  his teachings to out-of-towners by inviting them to pitch a tent during the longer workshops, giving folks nationwide the opportunity to attend.

You can read the original article, Teaching Others How to Be Green, on the emissourian website. 

One type of wind turbine that’s been getting a lot of attention these days is the vertical axis wind turbine. Even famous Hollywood stars like Ed Begley, Jr., are touting their supposed advantages over conventional wind turbines.

In a vertical axis wind turbine (VAWT), the blades are attached to a central vertical shaft. The shaft is attached to an alternator located at the bottom of the shaft, sometimes even at ground level. When the blades rotate, they spin the rotor of the generator, producing electricity.

Vertical axis wind machines have been around for a long time, about 3,000 years. The reason you see so few of them is that they’ve failed miserably.

That hasn’t stopped inventors (who are apparently unaware of their disappointing history) from rolling out new models and singing their praises. One refrain in their song of praise is that VAWTs can capture wind from any direction, which is true of horizontal wind turbines, too. The difference is that VAWTs are always oriented into the wind whereas conventional wind turbines turn into the wind as wind direction changes, thanks to the tail vane. No big deal there.

Proponents also like to claim that VAWTs are immune to turbulence that wrecks havoc with horizontal axis wind turbines (HAWTs). Turbulence is crazy airflow that occurs downwind from buildings and other obstacles on the ground, known as ground clutter. In turbulent areas, winds can flow in a number of different directions. This, in turn, is pretty hard on conventional wind turbines and one reason they are mounted on tall towers. Tall towers place them in the smoother, stronger, more energy-rich higher-level winds.

The VAWT does have a slight advantage in dealing with wind direction shifts, but turbulence also wreaks havoc on their blades, increasing fatigue. Fatigue leads to failure. Blades can crack and break.

Another supposed advantage is that VAWTs can be mounted close to the ground — even on top of buildings — where they capture ground-level winds. This eliminates the need for tall and costly towers and the need to obtain the zoning variances sometimes required to install horizontal axis wind turbines on tall towers.

Although VAWTs can capture ground-level winds, just like any turbine installed on a short tower, ground-level winds are subject to friction. This slows wind down as it sweeps across the land. Both friction drag and turbulence in lower-level winds around buildings and trees decrease the power available to a turbine mounted at ground level — so much so that there is very little extractable energy in them. The lower the wind speed, the less electricity a turbine will produce.

In addition, dead air spaces form behind buildings and other ground clutter. Placing a VAWT in such a location renders it useless. Even though you can mount a VAWT at ground level, there’s not much energy for them. You could mount a solar electric module inside your garage, too, but it’s not going to do much.

Unfortunately, years of experience with VAWTs has been rather discouraging, to say the least. Hundreds of commercial VAWTs were installed in California in the late 1980s and early 1990s. They all failed and were removed from service. These were not experimental units, but production units.

VAWTs are also less efficient than horizontal axis wind machines. For a given swept area, they just don’t extract as much wind energy as a well-designed HAWT. In addition, the blades of VAWTs are prone to fatigue created by centrifugal forces as the blades spin around the central axis. The vertically oriented blades twist and bend as they rotate in the wind. This causes the blades to flex and crack. Over time, this causes the blades to break apart, leading to catastrophic failure.

VAWTs are less reliable and efficient than HAWTs. All in all, they just don’t stack up against horizontal axis wind turbines. Don’t be fooled by the chatter of the ill informed — our friend and ally Ed Begley, Jr., included.

To learn more about VAWTs, check out Wind Power: Are Vertical Axis Turbines Better? You also may want to sign up for some of our courses at The Evergreen Institute or read my newest book, Power from the Wind. This book should be available by mid April in major bookstores and online at The Evergreen Institute and New Society Publishers.

Several readers have questioned the validity of my assertion that energy efficiency can dramatically reduce the initial cost of a solar electric system. In my blog Making Solar Electricity Affordable, I noted that each dollar invested in efficiency could save $3 to $5 in initial costs. The reason for this is that it is much cheaper to save energy than to generate it with a photovoltaic (PV) system.

To illustrate my point, I’ve included a table from a book I am publishing later this year entitled Power from the Sun. It’s an introduction to solar electricity that’s being be published by New Society Publishers. This data was provided to me courtesy Kurt Nelson, an experienced PV installer and teacher.

In Table 1, I list four energy efficiency measures and how much they’ll save a homeowner in watt-hours (column 4). Column 5 shows the cost of each measure.

Table 2 lists the daily and annual savings in kWh and the total cost of the improvements. It also lists the annual savings and the cost of the system. As you can see, the return on investment is 5.5 percent. These measures will save about 1,296 kWh of electricity per year. These changes cost nearly $1,700.

Now, here’s where things get interesting. Table 3 shows how much it would cost to generate this same amount of electricity via a grid-connected solar electric system — the cheapest of all PV systems. A PV system that generates 1,296 kWh per year would cost about $10,000 in Wisconsin. As you can see, it is nearly six times more expensive to generate electricity than to conserve it.

Factoring in the 30-percent federal tax credit drives the system cost down to $7,000. Even so, it is still four times more expensive to generate electricity via a PV system than to save it through efficiency measures. Every dollar invested in efficiency would save $4 in system cost.

Remember, energy efficiency measures will reduce the initial cost of battery-based systems even more, because batteries add substantially to the cost of these systems. And, off-grid systems don’t qualify for federal tax credits. In this example, an off-grid system that produces 1,296 kWh of electricity per year could easily cost $14,000. In this case, a PV system is 8 times more expensive than efficiency. Every dollar you’d invest in efficiency could save $8 in installation costs.

All this is to say, that efficiency measures are far cheaper than a new PV system. I’m not trying to discourage people from installing PV systems, just trying to encourage people to implement efficiency measures first. That way, you’ll end up spending less on a PV system.

Years ago, a friend told me a story of an acquaintance with strong environmental leanings who hoped to teach his children the importance of nature and environmental protection. One day, while riding in the car with his children, her friend was giving a friendly lecture to his children on the value of recycling. When he had finished, his son asked, “Dad, if recycling’s so good, why don’t we do it?”

Over the past decade, I’ve spoken to hundreds of audiences about environmental protection, many of which were populated by environmental educations and environmental enthusiasts. Numerous people in my audiences have admitted to me in private that they don’t do enough — or don’t do much at all. They talk a good talk, but don’t seem to be able really to walk their talk.

Leo Tolstoy may have said it best, “Everybody thinks of changing humanity and nobody thinks of changing himself.” A cynical friend once remarked, “Environmentalists are people who want to tell others how to live.”

While I know many dedicated environmentalists who really walk their talk, I know a fair number who “think globally, but act vocally.” They complain and provide advice for others, but don’t do much to help make a better world. To them, knowing the answer is not always living the answer.

If you’re one of those individuals whose sentiments and actions are out of alignment, here are fifteen steps you can take to dramatically reduce your impact and help create a truly sustainable future.

1. Install compact fluorescent light bulbs in the most commonly used light fixtures in your house.

2. Hire a professional to perform an energy audit on your home, then weatherize your home and beef up the insulation.

3. Install and use a programmable thermostat. It will cut your heating and cooling bills by 10 percent or more.

4. Plant shade trees to keep your house cooler in the summer.

5. Install water-conserving fixtures such as water-efficient showerheads and water-efficient toilets.

6. Replace worn out appliances such as clothes washers, dishwashers, furnaces and air conditioners with energy and water-efficient models. Buy Energy Star qualified models.

7. If you water your lawn, water early or late in the day and replace water-hungry grasses with low-water grasses, and remove sections of lawn that are hard to water and wasteful of water.

8. Recycle all household waste from newspapers to cardboard to aluminum to glass.

9. Compost all kitchen scraps (except meat and bones) and yard waste. Compost in your backyard and use the compost to enrich the soils in your flower and vegetable gardens.

10. Eat more vegetables and less meat. Buy organic vegetables whenever possible.

11. Carpool, ride a bike, walk, or take the bus whenever possible.

12. Replace gas-guzzling vehicles with fuel-efficient models getting 40 miles per gallon or more.

13. Curb consumption. Learn to live more simply. Buy less. Buy used goods. Practice green gift giving.

14. Reduce the number of pets you keep. Hard as it is to swallow, our pets have a huge impact on the environment, one rarely discussed these days for fear of offending pet lovers. Cats, for instance, kill several hundred million songbirds each year. Pets such as cats and dogs produce mountains of solid waste that may wash into nearby streams during heavy storms. Feeding cats, dogs, parakeets, cockatiels, and other pets also requires enormous acreage, land that was once wildlife habitat, and energy for processing and shipping food.

15. Drop those extra pounds. Weight loss is another important environmental strategy, though never mentioned. Today, over 60 percent of all American adults and 15 percent of all children are overweight. They take in more calories than the need. In fact, the average American requires 2,200 calories per day, but consumes 3,200 — 1,000 calories extra, which accounts for the extra poundage that leads to late-onset diabetes, heart attacks, and other medical problems.

Consuming calorie-rich food in excess, which has become something of an American pastime, is not only unhealthy it requires more resources. The more food we eat, the more land is required, the more energy and materials are used, the more fertilizer that’s needed, the more pesticides are applied to our land, and the more pollution is produced. Taking care of health problems also requires massive amounts of money and resources.

By eating less and maintaining health, we can lower our environmental impact — and quite dramatically.

These steps can dramatically reduce your impact on the environment, the first step in building a sustainable future.

Most of the steps are easy. If you put your mind to them, change your priorities, refocus on your values and commit to living by your ideals, well, anything is possible.

And if hundreds of thousands of people in each state follow suit, we can make huge inroads into current problems and help steer our society back onto a sustainable path.

Many people are asking me whether the economic recovery plan will stimulate jobs in green energy and green building. My answer is yes. Definitely.

What areas will we see growth?

One hot area, of course, is renewable energy — solar electricity, wind energy, geothermal and others. Expect jobs in residential renewable energy as well commercial renewable energy production.

Energy efficiency could be even bigger. These measures offer the most benefit for the least cost.

I expect a lot of jobs in green building, too, at residential and commercial levels. I just read Five Hot Future Careers — Train Now by Woodrow. Aames says that green construction management will be one of the top new jobs in the near future — and a lucrative one, too.

If you are interested in a career in residential green building or renewable energy, be sure to check out our workshops at The Evergreen Institute.

With renewable energy and efforts to combat global warming high on the list of national priorities, Dan Chiras, Mother Earth News contributing editor and founder of The Evergreen Institute recently announced the opening of the Center for Renewable Energy and Green Building, an educational center in east-central Missouri.

The Center for Renewable Energy and Green Building offers hands-on instruction in solar electricity, wind energy, passive solar design, residential energy efficiency, green building and natural building.

The courses are taught primarily by author and educator, Dan Chiras. Chiras has taught at the college level for 32 years. His books include The Homeowner’s Guide to Renewable Energy, Power from the Wind, Green Home Improvement, the Natural Plaster book, The Solar House and The Natural House.

Chiras consults on residential green building and renewable energy throughout North and Central America.

The first three courses at the Center (April 18, 19 and 20, 2009) are Home Energy Efficiency, Basic PVs and Intro to Wind.

The Evergreen Institute also offers Certificate Programs in Residential Green Building and Residential Renewable Energy for individuals interested in pursuing a career in green building and/or renewable energy or individuals interested in furthering their professional credentials in these burgeoning fields.

The Evergreen Institute is working in partnership with the Midwest Renewable Energy Association and The University of Colorado’s Continuing Education and Professional Studies Program.

To learn more, visit The Evergreen Institute, e-mail info@evergreeninstitute.org or call 303-883-8290.

Americans have become conditioned to expect immediacy. Cell phones, faxes, computers, Internet access, overnight mail and text messaging give us instant access to friends and families and a wealth of information. It’s all there at our fingertips.

Thanks to computers and the Internet, we can go online today, research a product in depth, order it, and have it on our doorsteps the next day. We can text a friend in China or India and receive an immediate response. And, we can access a boundless amount of information without so much as a single trip to the local library.

Unfortunately, our conditioning is a detriment. As we struggle to rebuild our economy, impatience is rearing its ugly head. Critics are already casting doubt on the economic recovery plan recently signed by the president, not giving it a moment to take effect.

We forget that it took us a while for the crisis to unfold. The economic crisis probably started with the burst of the tech stock bubble. Then came 911, an event that knocked our economy to its knees. Then came the invasion of Iraq, and the high price tag, which drained our economy.

And don’t forget hurricane Katrina, with a price tag of over $150 billion, and countless other disasters all brought on by global warming. Each one cost us dearly — in lives, in property loss and in dollars. Each one helped weaken our economy.

Tax relief to America’s wealthiest probably hurt the economy as well, decreasing revenues in a time when spending for wars in Iraq and Afghanistan reached record levels.

The high price of gasoline, dealt a blow to our economy as well. And then came the subprime mortgage meltdown. It was the last straw and knocked the already severely weakened legs right out from under our economy.

Let us not forget that the current crisis took a long time to unfold, and will take a long time to solve. We must remain patient — and do our part to prevent the kinds of things that got us here in the first place.

Many people who are contemplating installing solar electric systems on their homes struggle with the high initial costs. To pay for a system, they either have to dip into their savings or take out a loan. A 3- to 5-kW grid-connected solar system, suitable for most homes, can run $30,000 to $50,000.

Even with recent legislation that provides a 30 percent tax credit for solar and wind systems for homes and businesses, the cost of such as system will still cost $21,000 to $30,000, which is a substantial piece of change.

Isn’t there some way to reduce this cost?

There is. It's called efficiency.

Richard Perez, founder of Home Power magazine, ran the numbers. He found that every dollar invested in energy efficiency could reduce the cost of a photovoltaic (PV) system by $3 to $5.

How?

By reducing the size of a system one must install to meet his or her needs. The economic savings from efficiency are quite substantial. For instance, a $2,000 investment in home energy efficiency — for example, weatherization, insulation and energy-efficient compact fluorescent or LED light bulbs — will reduce the demand for electricity. This, in turn, will reduce the size of the PV system required to meet one’s needs. It could easily save $6,000 to $10,000 on the cost of the system of a 3- to 5-kW PV system before tax incentives. Taking into account the 30% federal tax credit, the savings would be $4,200 to $7,000.

Spend a little more on efficiency and the cost of the system drops even more. If you invested $4,000 in efficiency, the total system cost would decline by $12,000 to $20,000. Taking into account the federal tax credits once again and the decrease in initial cost would be $8,400 to $14,000.

That’s not a bad return on an investment in efficiency.

Instead of spending $21,000 to $30,000 for a system, you’d pay $12,600 to $16,000.

So, if you're thinking about installing a PV system, think efficiency first. It’s a gift you give yourself and the planet. It will reduce energy demand, reduce pollution, and reduce the cost of a system substantially. Moreover, the savings will provide dividends for the life of the house.

The United States is struggling to restore its economy, when it should be working to reshape or rebuild it. There’s a profound difference between the two.

Unfortunately, in our panic to revive the economy many of our congressional representatives have failed to fully realize one fundamental fact: Not all dollars are created equal.

New highways, bridges, and economic stimuli that return the economy to its former state and end up putting more people back into gas-guzzling RVs or too-large or energy-stupid homes do not hold a candle to stimuli that promote home weatherization, new wind farms and green transportation.

Let’s be fair. The economic recovery package recently passed by Congress provides funds for jobs and businesses that promote sustainability like energy retrofits, renewable energy and green transportation. But I fear that much of the rest is meant to simply restore business as usual.

As many who have responded to my first blog realize (A Smart Road to Economic Recovery), we can’t solve the problems we’ve created with the same logic that created them. So what do we do?

I urge all readers to write or call their legislators and write editorials in their local newspapers emphasizing the need to promote sustainable economic activity. What should we be promoting?

How about a solar hot water system on every home in America? How about incentives or requirements that all new homes be built to exacting energy-efficiency standards? How about incentives or laws that require solar electric modules on every government building, office building and new home? How about moving forward the deadline on which auto manufacturers are to achieve higher fuel efficiency standards?  How about laws or incentives that promote the use of green building materials, recycled products in all aspects of society, organic farming, environmental education in K-12, water conservation, and restoration of damaged waterways, farm fields and forests?

Let’s be specific.

Let’s propose a list of action items that contributes to a truly sustainable society — one that makes sense for people, the economy and the environment now and over the long term. 

And as some of you have suggested, let’s vote with our dollars, too. Let’s take steps personally to promote these activities, starting in our own homes and businesses. We can’t wait for Washington to solve our problems. We must take action individually. If not us, who? If not now, when?

As the U.S. economy continues its downward spiral, the media’s role in promoting growth and consumption become blatantly obvious.  Newscaster after newscaster and analyst remind us that roots of our downturn are weak consumer spending brought on in large part by the subprime mortgage fiasco.  Some in government propose tax cuts to prop up spending. The central theme in the discussion is that if consumer spending can be sparked once again, all will be well.

Not-too-subtly, we (the spending public) are enjoined to perform our “duty” as good citizens of the economy — to consume more. We’re told that we can pull a nation out of the crisis and restore economic prosperity by simply prying open our wallets.

It’s no surprise that citizens of this country are no longer referred to as such, but as “consumers,” a term that emphasizes our vital role in a consumer culture led by corporations and advertising firms paid to do their bidding 

Over the years, we’ve become a nation of consumers addicted to growth. We uncritically subscribe to the notion that “growth is good, indeed essential.”  Growth is predicated on the consumption of goods and services, some essential, many not, by good citizens like you and me.

Now spending is seen as the salve for this wounded economy. No matter that our continued acts of consumption could very likely lessen the chances of our long-term survival on the planet. What is even more distressing is that we’re raising our children on the same logic.

In recent days, we’ve learned that citizens are saving more. Some economists view that as bad for the economy, even though saving rates in the United States have previously plummeted into the negative range (we’re spending more than we make).

As we reshape our economy, not only must we restore jobs, but we must restore sanity: careful buying, judicious saving and living within our means. My hope is that we can create an economy that also focuses on sustainable activities, like renewable energy and long hikes in the wilderness, not big screen TVs and monster SUVs.

My fear is that to create a recovery, we’ll embrace any idea that puts people back to work, regardless of its impact on the environment, our long-term economic health and environmental sustainability.

Contributing editor Dan Chiras is the founder and director of The Evergreen Institute and president of Sustainable Systems Design, Inc.