Tag Archives: sustainability

wind turbine

Windy Arguments

The internet can be a veritable fount of information, but also a source of of disinformation. It is easy for an industry to hire bloggers to write confusing, disingenuous, and even deceptive posts about other industries to gain a competitive advantage in the marketplace. No where is this more obvious than the struggle between the fossil fuel industries and sustainable energy supplies such as wind and solar.

Wind generated power has taken a lot of derision, mostly undeserved, from the flacks for the fossil fuel industry, so let’s talk about wind energy.

Wind is expensive due to the production tax credit? Although the current production tax credit (2.3 cents per kWh) has expired, it may be reinstated. So, yes taxpayers are subsidizing wind power, to the tune of about six billion dollars a year. How does that compare to the subsidization of the fossil fuel industry? Just the health care costs due to burning fossil fuels is estimated to be the equivalent of 8 to 30 cents per kWh, or several hundred billion dollars a year.

Wind Turbines kill birds? Estimates are the wind turbines kill about 25 thousand birds a year, about 90 per cent songbirds, and the remainder raptors such as hawks and vultures. But is this rate of bird deaths important compared to other human caused bird mortalities? Total human caused bird mortalities are a billion birds a year. Collisions with buildings cause close to half a billion deaths. Cats, both pets and feral, kill about a 100 million. Cars, trains and planes cause another 100 million. When one considers total bird deaths, wind turbines would hardly rate a foot note.

What about human deaths? One can compare just how deadly wind turbines are by comparing the death rate per unit of electrical energy used. Wind deaths are 0.15 deaths per TeraWatt-hours per year. Competing technologies such as electrical energy from burning coal are 15 deaths per TWh/year and for Oil 36 deaths per TWh/year. Burning fossil fuels produces hundreds of times as many deaths.

And Jobs? Here we compare jobs created per million dollars spent on energy. Oil and gas, one job; coal, two jobs; wind five jobs. Interestingly building retrofits to save the same amount of money on energy is the winner with eleven jobs.

Wind turbines are noisy?

wind noise

wind noise

But just how noisy? Modern turbines have incorporated features that reduce noise from the swooshing blades and squeaking generators. The noise level at a distance of only three turbine blade lengths is rated as acceptable. The noise from a turbine a few suburban lots distant would be no louder than standing near a humming refrigerator, about 45 decibels.

But they’re ugly?

Nantucket site

Nantucket site

A large off shore wind project in Nantucket Sound will supply much of the electrical energy of Cape Cod, MA. It has been resisted by some local residents as unsightly. Not surprisingly Bill Koch, a coal and oil magnate, has provided 1.5 million dollars to lobbyists and a group called the Alliance to Protect Nantucket Sound.

Environmental Stewardship

This time of year we tend to look back on the past year, resolve to do better next year, or at least think about what the future will bring. In terms of energy supplies, we have in past years continued our reliance on highly subsidized fossils fuels, the use of which endangers the environment and contributes to our spiraling health care costs. Will we in the future resolve to be less wasteful? Will we resolve to do better as stewards of the planet, for our children’s sake?

The twentieth century will be looked upon as the heyday of fossil fuels, first coal, then oil and now increasingly natural gas. The availability of these fuels produced in North America is increasing which is good for the economy, but bad because the increase utilization of fossil fuels. This is bad for the environment and our health. There are two broad alternative futures;

hard vs soft energy paths

hard vs soft energy paths

business as usual where we favor big solutions like increasing reliance on nuclear reactors and abundant coal reserves, or what Amory Lovins described as the “soft energy path”. In this alternate future energy will be supplied by sustainable, dispersed energy sources such as wind and solar.

The big solution is basically a supply side, large scale strategy which favors production to meet demand, rather than the management of demand to impact production. Nuclear power in one form or another is realistically the only long term solution in this pathway. Due to economy of scale issues, nuclear reactors are very large, when measured by energy output. And unlike the suggestions of the fifties, nuclear power is not and will never be “too cheap to meter.”

And of course there is the yet to be solved problem of high level nuclear waste. Because of these problems the industry is both highly regulated and highly subsidized. The nuclear industry of the future, if it has a future, will be regulated so that the consumer is protected somewhat from the economic and environmental vagaries of energy production, but that will result in a larger governmental role to oversee said industries. This is the classic big industry, big government system which has been the historical trend over several generations. And it has worked more or less in not only the energy industry specifically but the economy in general. OK, there is the problem with the rich getting richer and the poor getting poorer, but that has also been the trend of late.

The soft energy path envisions power production to be greatly decentralized. When power is coming from wind turbines or solar panels economies of scale are not nearly as significant. Solar and wind will be done on a much smaller scale, as suggested by Kirkpatrick Sale in his book “Human Scale”. Power will be produced by individuals or local coops, with less need of big government oversight as the risks are considerably less. Production will be controlled by demand management through more emphasis on efficiency. In this strategy there is less need for big government, and less likelihood of extremes in wealth accumulation, at least in the energy sector.

So these are our possible energy futures as viewed through two extremes. I prefer the latter, but we will see what the future brings.

Lighting Technology

The phrase “She would rather light a candle than curse the darkness” came from a Eulogy given by Adlai Stevenson for Elanor Roosevelt. This is of course a metaphor, as the bringing of light refers to bringing knowledge to an unknowing hence dark world. Aphorisms aside, let’s be literal. Let’s talk about lighting technology.

There is good evidence that one of our ancestors, Homo erectus learned to control fire close to a half a million years ago. Fire provided heat, protection from predators, and light to extend the day into night. The campfire of Homo erectus was wood and provided much more light than heat. Light was a byproduct.

Technology expanded light production with the creation of oil lamps about six thousand years ago. Made from clay, lamps were found at numerous sites, and depending on location these were fueled by animal fat, vegetable oil or even petroleum oil from natural seeps. The related technology of candles came later, possibly originating in China about three thousand years ago. The Chinese candles were made of whale fat. Other materials for candles include tallow, beeswax, and contemporaneously paraffin, a solid petroleum derivative.

Kerosene lanterns, still in use in much of the world were common by the nineteenth century. Gas lamps, using gas as opposed to liquid developed about the same time and were popular as stationery light sources, e.g, street lamps.

All these light sources share one property – combustion. Burning something, combustion, is an exothermic process. Burning gives off heat, and if you give off enough heat you get (visible) light. Thomas Edison recognized that if you get something hot enough, whether burning or not, you get light.

Incandescent 16 Lumens per watt

Incandescent 16 Lumens per watt

His invention, the incandescent light bulb (ILB) employing electricity, revolutionized lighting and has illuminated the modern world since the start of the twentieth century.

The new revolution in lighting technology is the production of light sources much more efficient than incandescent bulbs. ILBs work by the heat, then light produced by resistance to the flow of electricity through the Tungsten filament. But it is an astoundingly inefficient process when illumination is the objective. Only about five percent of the energy consumed by an ILB produces light, the remainder is given off in the form of heat.

Luminous efficacy is measured by the product of the amount of light measured in lumens, divided by the energy to power it measured in watts. The luminous efficacy of an ILB is sixteen lumens per watt.
ILBs are cheap to produce but waste energy. More efficient are compact fluorescent bulbs (CFB).

a 100 watt equivalent clf uses about 28 watts

a 100 watt equivalent clf uses about 28 watts

These have a luminous efficacies of about fifty to sixty. They are therefore cheaper to operate but have a few drawbacks; they take time to reach full illumination especially at low temperatures, they aren’t dimmable, and they contain small amounts of Mercury which complicates disposal.

The most promising entry to inexpensive lighting are Light Emitting Diode light sources. They are everywhere already in electronic technology in the form of various indicator lights. These LEDs have now been ganged in groups to produce illumination with efficiencies of over one hundred.

100 watt equivalent LED uses less than 22 watt

100 watt equivalent LED uses less than 22 watt

LEDs don’t suffer from the deficiencies of other bulbs; they are very efficient, “instant on”, dimmable, cool to the touch, non toxic, and will become even more efficient as they are developed. The future for LED lighting is bright indeed.

high speed rail

Trains, Here and There

Automobile use as measured by miles traveled per capita peaked in 2005 and has been falling since. It is had to explain by a single variable, gas prices have been both up and down, not continuously up. We went through the worst recession since the great depression, but the economy is now improving, albeit slowly. Vehicles are becoming smaller so less accommodating for passengers but more efficient thus cheaper to operate.

Regardless of the reason, we are moving around less; and, there has not been a concomitant increase in mass transit. Is it time for us here in the US to consider an emphasis on mass transit to the degree that is available in Europe or the far east? Travel by train there is easy and frequent. You want to go from Edinburgh, Scotland to Bucharest, Romania, 1700 miles? There are trains for that, and daily I might add.

Not only can one travel long distances between large cities, but also short distances to small towns as well. There are nine different departure times daily from Chepstow, Wales to London, England (Chepstow is a town about the size of Clarksville, AR.) This would be equivalent to a train, nine times a day from Clarksville to Little Rock.

But we’re all about speed, right; and trains are too slow. Well they’re not so slow in Europe or the far East. Speeds between one and two hundred miles per hour are common.

European high speed rail

European high speed rail

And unlike the USA; Japan, Korea, and China are all investing in infrastructure which will allow for faster, more efficient trains.

China currently operates a fourteen hundred mile rail at over two hundred miles an hour, and is expanding rail service faster than highways or airlines. When a high speed rail became available in Taiwan most passengers switched from the comparable air route, and highway congestion decreased.

Technological advances in Japan involve a Maglev train. Maglev is short for magnetic levitation, where levitation of the train above the rails means a near frictionless and therefore faster, quieter and more efficient rail line. The train has been successfully tested on a short track at over three hundred miles an hour and expects to be in service by 2015.

What about American Exceptionalism? Is anything unique going on here? One bright spot is California which has proposed a high speed rail line between Los Angles and San Francisco. The voters in California have approved close to ten billion dollars to develop the line, which at two hundred miles an hour would complete the trip in two to three hours. Current driving time for the trip is seven or eight hours.

A real game changer has been proposed by entrepreneur Elon Musk, who designed and sells the Tesla, a successful all-electric car. He wants to build a Hyperloop, basically an evacuated tube,

hyperloop

hyperloop

to transport people at eight hundred miles per hour. The technology is the same as that used to move money and checks from the remote teller to your car at the bank. The trip from Los Angles to San Francisco would be about a half an hour and if similar technology existed locally one could go from Little Rock to Dallas in about twenty minutes. Now that would be both exceptional and American.

Professor Mark Post holds the world's first lab-grown beef burger during a

Petri Patties – Lab Grown Meat

Even though we have yet to recover from the current recession, we still lead the world in economic might and that is reflected in our high rates of consumption of everything from crude oil to meat. Both of these commodities contribute to our exaggerated contribution to global warming.

As other countries expand their economies, that is become more wealthy, they tend to eat more meat. China in 1961 consumed four kilograms per person. By 2001 that jumped to fifty-four kilograms. Currently half of all pork produced in the world is consumed in China. By comparison the US eats over one hundred twenty kilos of meat per person per year. By the year 2050 global meat consumption is estimated to double, from the current 230 to 465 million tons.

The connection between meat consumption and wealth is easy to see. Protein from meat is expensive. The cheaper alternative comes from diet that balances beans and grains to provide complete protein – nutritious but bland. So what’s the harm if you can afford meat? Two factors; personal health effects such as heart disease correlate with high meat diets, and meat production contributes to global warming.

Enter the lab burger,stage left – PETA has a bounty out for the first practical lab grown meat. A study done a couple of years ago suggests that if meat could be “grown” in the lab, about 50 per cent less energy would be used, virtually no land would be needed, and ninety per cent less green house gases would be emitted compared to traditional agricultural methods. These environmental improvements result from considerable decreases in methane release from ruminants and decreased deforestation not needed for feed; corn and soybeans, and fodder; grass from pastures.

We now have a Petri patty, not practical by any measure but at least the proof of concept has been achieved. Last month a celebrity chef in London, England prepared the world’s first and only hamburger made from meat grown in cell culture in a laboratory in the Netherlands. The idea of lab meat is not new. As early as pre-world war II, Winston Churchill wrote about the possibility. He was concerned that a war which resulted in a blockade of the UK could threaten the population with starvation.

The process is simple in principle but extremely difficult in practice. The simple explanation: take a muscle cell from a cow, stimulate the cell to divide in a nutrient broth, and voilà! The lab burger. In practice the process took several years and over four million dollars. Tissue harvested from a carcass is first treated with an enzyme to remove connective tissue and release the muscle cells. The cells are cultured in fetal bovine serum, a fluid taken from slaughtered calves. Alternative cell culture media exist but performed poorly. Because the cells lack any vasculature the cells can only be grown in thin films. Also methods had to be developed to “exercise” the developing muscle tissue.

One final problem is physical, the cells are colorless and without fat so the lab meat was colored with beetroot juice and cooked in butter and oil. For cultured meat to become a real alternative it has to be a whole lot cheaper, redder and fattier.

Colorado River

Extended Drought in Southwestern US

One of the projections of climate change due to global warming is alterations in rainfall patterns. Warmer air will hold more moisture so one might think that global warming will cause more rainfall and generally that is true overall, but another feature of global warming is a redistribution of rainfall, more falling on the coasts and less in the continental interior.

Additionally, the rainfall patterns are predicted to change to more intense storms where larger amounts of rain occur over shorter time spans. Heavy rains mean more runoff, hence less water available for the myriad of uses we depend on – energy production, agriculture, industry, recreation and most importantly drinking water.

>The Colorado River and its tributaries drain a basin of a quarter million square miles. Forty million people in six western states [Colorado, New Mexico, Utah, Wyoming, Nevada, Arizona] are directly in the line of fire of climate change. For millions of years the Colorado has flowed from the upper reaches of the Rockies to a large delta at its confluence with the Gulf of California.

Not so much any more. A combination of drought and pressure on the river from agriculture and burgeoning cities has reduced the flow to the point that in recent years the Colorado no longer reaches the sea. Virtually every drop is removed for irrigation in the Imperial Valley of California, to cool coal-fired power plants around the Four Corners area, and to water golf courses in Phoenix.

Global warming and the attendant climate change is predicted to decrease precipitation by twenty percent in the watershed over the next forty years. This will greatly exacerbate the issue of the availability of water in the southwest. The water level of Lake Powell,

Lake Powell on Colorado River

Lake Powell on Colorado River

formed by the construction of the Hoover Dam is at an all time low, some 120 feet below its high of a decade ago. Images show what appears to be a “bathtub ring” on sandstone bluffs along the lakeside.

Another distressed southwestern watershed is the almost two thousand mile long Rio Grande which demarks much of the border between the US and Mexico. The two hundred thousand square mile basin has been stressed by a decade long drought, and it appears to be getting worse due to global warming. Two significant reservoirs, Elephant Butte and Caballo are at less than ten per cent capacity.

Elephant butte Reservoir

Elephant butte Reservoir

Like the Colorado, the Rio Grande doesn’t make it to the sea. What little flow exists is removed, mainly for irrigation. The flow essentially ends by the time it reaches Presidio, TX.  Other significant water courses in China, India and Australia are distressed to the point of no exit flows. The problems are real and worsening with increasing population demand and climate change.

Global warming is real, we are causing it and we need to address how to stop,even reversed it, in addition to the immediate need for adaptation to the new climate we are forcing.

pvbob

What about China?

There is a consensus among virtually all scientists that humans, by burning fossil fuels, are contributing to global warming and thus changing the climate. The climate has changed many times over the billions of years of earth’s existence, so what if we are changing it, why does it matter?

It matters because we are changing the climate on a timescale never seen before; hundreds, even thousands of times faster than any naturally occurring climate change. We are changing the climate at a rate which can cause massive extinctions as plants and animals fail to adapt.

The only viable solution is to stop burning fossil fuels. Coal, oil and natural gas represent carbon that was removed from the atmosphere over hundreds of millions of year. We are burning up these fuels at a prodigious rate, returning all that carbon to the atmosphere over a couple of hundred years. This has resulted in much, much higher concentrations of heat trapping gases and particulates in the atmosphere. Additionally we are making the oceans much more acidic.

We have to stop! We have to decarbonize as quickly as possible. We have started but only by baby steps. The fastest growing carbon free alternative for producing electricity in the US is wind power, which has increases by thirty per cent over the last five years. That’s the good news, the bad news is that that represents less than three percent of our total production.

Our solar electric production has increased by a phenomenal five hundred per cent, but has further to go with only a tiny fraction of one per cent of total electric production. We have a long, long way to go. And there are impediments. One argument against abandoning fossil fuels is that we will be at a competitive disadvantage with other countries that continue to rely on fossil fuels.

So what are our economic competitors doing? What about China? If the objective is to limit carbon release to the atmosphere but China isn’t why should we? And India, if India is still polluting, why do we have to stop? You know in some childish, schoolyard way I guess that makes sense. But we need to be adults about this. We need to provide the global leadership to show the world how it can and should be done.

The US consumes close to one quarter of the world’s resources, yet we constitute a bare five per cent of the global population. It shouldn’t be a matter of what others are doing, but what we need to do to get our house in order.

Actually the “what about China” question is an UH-OH. China is already the world leader in wind power; growing by leaps and bounds, twice as fast as the US over the past five years. How about wind generation as a fraction of total energy production?

wind

wind

Denmark beats us by an order of magnitude, with over twenty per cent of total electric production from wind.

We are similarly behind for solar electric. China is the world leader in the production of Photovoltaic panels, and Germany leads in per capita production, over twenty times the US ratio.German-Solar-Houses

We still have the largest economy in the world and if we were to invest in renewables we could be a world leader in preparing for a carbon-free future. Think American Exceptionalism.

Geothermal Heat Pumps

The term geothermal when applied to heat pump technology means that the ground is used as a heat exchange medium, rather than the air. Heat pumps are nothing more than reversible devices to heat and cool a home.

The technology is the same as refrigeration. When a gas expands, it absorbs energy from the air, thus cooling the surroundings. Refrigeration works by using a pump to compress a gas, called the working fluid. The compressed gas, now a fluid, is moved to the area to be cooled and then allowed to expand. The heat being moved by a heat pump is expelled away from the area to be cooled. For most systems, “away” is the air outside the house.

The hotter it is outside in the summer, the harder a heat pump has to work to cool your home. This is where the ground comes into play. Geothermal heat pumps use the ground as “away”. The heat exchanger portion of a geothermal heat pump is connected via wells drilled or lateral lines on the property to water or some other liquid which transfers the heat to the much cooler ground, rather than the much warmer air. This process is more efficient at moving heat, and therefore summer cooling costs are lower.

The process is reversed in the winter. Compressing a gas inside a home produces heat, then the compressed gas is moved out of doors and allowed to expand and cool out of doors. Heat pumps are quite efficient at heating in the winter as long as the temperature is not too low. The colder it gets the less efficient the system. For a geothermal heat pump, it doesn’t matter what the air temperature is because the heat exchange is with the ground which is about fifty to sixty degrees Fahrenheit year round. In the winter the ground is warmer than the air so geothermal heat pumps are more effective than traditional air source systems.

Overall geothermal heat pumps are more efficient than normal air source heat pumps, particularly during the temperature extremes of summer and winter. In a study at Fort Polk Louisiana, heating costs during winter days below freezing were forty per cent lower. During the summer days with the temperature over ninety degrees, the costs of cooling were also about forty percent lower with the ground source heat pumps compared to air source heat pumps.

Heat pumps work best when the difference between the outside and inside temperatures are not great. Geothermal heat pumps take advantage of the more stable ground temperature, keeping the difference lower than for air source heat pumps.geothermal_heat_pump2

ground-source-heat-pump3

Geothermal systems require the drilling of wells or laying lateral lines to create the ground contact so the systems are inherently more expensive that simple air source systems, but because of their greater efficiency, usually have payback periods on the order of five to ten years.

The Anthropocene

Scientists in general and particularly geologists measure time on our planet in epochs. For example the time from two and a half million years ago until twelve thousand years ago is called the Pleistocene. This time period was characterized by a series of long glacial periods. The current epoch is called the Holocene which began with the worldwide recession of the glaciers.

Recently some scientists have called for the naming of a new epoch called the Anthropocene, characterized by human influence on the planet due to our transformation of the atmosphere over the last two hundred years. Others contend that the start of the Anthropocene should be counted as starting much earlier. Modern humans have influenced the planet by churning the biosphere for close to a hundred thousand years. Our mobility has resulted in the movement, occasionally purposely, of many many plants and animals.

Wheat originated in Near East, corn in Central America, and rice in Far East. All are purposely cultivated world wide. The inadvertent introduction of some species has been the ruination of others. The inadvertent human dispersion of the black rat is a good example. It has caused the extinction of many bird, reptile, and other small vertebrate species across the planet.

The honey bee originated in Africa, and migrated to Europe. It was brought to North America by the colonists for honey production and has been a resounding success. Annually fourteen billion dollars worth of crops are dependent on honeybee pollinationhoneybee in the United States alone. Ironically the honeybee brought to North America by humans is now threatened by humans by the use of a class of insecticides known as neonicotionoids.

Non native earthworms were also brought to North America by the colonists but this time the importation was accidental. They came as part of the ballast of ships and in the soil of potted plants. Their introduction has been a mixed bag. Whereas home gardeners and those who fish extol the virtue of the earthworm, they are actually harmful to forests of northern North America.

Glaciers advanced to about the Missouri and Ohio Rivers and wiped out earthworms, if there were any to begin with. After the glacial recession, the forests returned and adapted in the absence of earthworms. The normal condition of the forest floor is a thick layer of slowly decomposing leaves. The presence of earthwormsearthworm accelerates this decay, removing an important organic layer that serves as seed beds for saplings, ferns, and wildflowers.

One of the newest accidental imports is another ant, called the Crazy AntCRAZY ANT for its erratic behavior and tendency to swarm. It first showed up in Houston TX and has been seen in southeast TX, southern Louisiana, southern Mississippi and and much of Florida. Where it occurs it either kills or drives out most other species of insects, spiders, small reptiles and birds. They will nest just about anywhere but are particularly fond of electrical wiring, causing a 150 million dollars a year damage in Texas alone.

We certainly live in a time of dramatic global human influence. We continue to change the composition of the atmosphere and hence the climate. We are making the oceans more acidic. We are dispersing uncountable numbers of species, generally with negative impact. And all these effects are causing extinctions of flora and fauna. My question for you is should we?

Carbon Capture and Storage

President Obama recently gave a speech at Georgetown University addressing global warming. He has recognized that limiting carbon emissions from power plants is an important step in reducing our contribution to the release of green house gases. One approach is the process where the Carbon Dioxide produced by burning fossil fuels such as coal is captured and stored, rather than released to the atmosphere.
 
If Carbon Capture and Storage (CCS) can be made to work, we could have our cake and eat it too.  That is, we could have the benefits of cheap energy without the negative consequences.   Basically CCS is a process of capturing the Carbon Dioxide waste stream from a power plant and then putting it somewhere other than the atmosphere.

The problem is that it is neither cheap nor easy. CCS technology could double the construction and operating costs of a power plant.   A further limitation is the need for storage sites such as airtight underground caverns or the ocean depths, where the carbon dioxide would stay for a long, long time. Like forever.
 
The best site would be a geologic formation where subsurface rock naturally reacts with carbon dioxide via a process which chemically mineralizes it. These formations exist but are few and far between. We need enough storage space for about thirty billion tonnes of carbon dioxide for this year and even more in future years due to growth.
 
Without mineralization, storage becomes much more difficult. Carbon dioxide, a gas at normal pressure, would need to be pumped into storage wells and the wells then capped to prevent release.  At atmospheric pressure it would require over six thousand cubic miles of underground open space per year. This kind of space doesn’t realistically exist, hence pressurization is necessary to reduce the volume.   The higher the pressure the more difficult it will be to contain the stored gas. Any leakage will increase the cost both economically and energetically- all that capture, transportation, and pressurization uses energy.
 
Another storage site to consider is the ocean depths.  The advantage of ocean storage is that the conditions of the abyssal plain are high pressure and low temperature.  Under these conditions carbon dioxide exists as a liquid with a volume only a fraction of that as a gas.   Slowly, the dissolved carbon dioxide would react with seawater forming carbonic acid. We would slowly turn the oceans of the world into salty soda water.  Rather than just sounding silly, it’s actually deadly.  The acidity created by the higher carbonic acid concentration would essentially sterilize the oceans.
 
The only way to store the thirty billion tonnes of carbon dioxide produced every year seems to be by pumping it at high pressure into every hole in the ground that we can find, plugging the hole and then hoping that the cap doesn’t come off, forever.  But what if a storage site does burp?
 
Lake Nyos is a crater lake in Africa.  Local conditions cause the lake to be supersaturated with carbon dioxide.  A limnic eruption occurred in 1986 for causes not entirely clear.240px-Nyos_Lake This event caused the near instantaneous release of close to 2 million tonnes of carbon dioxide. This is just like the classic mentos and diet coke eruptions, except deadly. The heavier-than-air gas killed about 1700 people and all their livestock.  This area was thinly populated or the death toll would have been much higher.
 
Carbon capture and storage, in the last analysis, is expensive, uses a lot of energy, and is quite risky to all life in the area of the storage wells.  Additionally Carbon Dioxide is only about half of the problem associated with global warming. The only real solution is abandon the use of fossil fuels and get all our energy from wind, solar and geothermal.