A Live Green, Live Smart™ Paper
Humankind's perennial concerns about environmental conditions have reached a surge of urgency. Issues that once seemed regionally distinct are now being recognized as globally pervasive. The threats to society of diminished air quality, persistent drought, lack of clean water, and destruction of agricultural lands have begun to seep into - but not quite penetrate - the collective social consciousness.
Meanwhile, policymakers and opinion leaders are recognizing with alarm that these problems actually result from global warming and the concomitant changes that the landscape of the Earth is undergoing. Debates have moved from skepticism and denial that there is any problem at all to acknowledgement of the environmental problems we face as a global community - some observers are leaning toward the ‘it might already be too late' side of the argument.
But many nations and individuals have taken steps in the right direction, converting to alternate energy sources such as solar and wind power, restricting ozone-depleting emissions from vehicles and factories, enforcing protection of forests and water. These changes in policy and practice are evidence of people's willingness to protect the world upon which our lives depend - and believing that it is not too late and taking steps to mitigate the damaging impacts of global warming and climate change will be essential to sustaining the quality of human life while we respond with determination and ingenuity to the causes, effects, and potential solutions to large-scale global climate change.
GLOBAL CLIMATE CHANGE
The phenomenon called global warming is an overall rise in the Earth's average temperature - a change in what is called climate. The creation of climate results from something called the Natural Greenhouse Effect. Essentially, what are referred to as greenhouse gases - carbon dioxide (CO2 ), methane (CH4), ozone (O3), nitrogen oxides (NO & NO2), and carbon monoxide (CO) - provide a "blanket" over the Earth. This layer scatters about 30% of sunlight back into space before it contacts the surface of the planet.36 The rest reaches the Earth's surface, and is reflected back through the atmosphere in a slow-moving energy called infrared radiation. The overall effect is that the Earth becomes heated with a natural warming effect allowing life as we know it to survive and even thrive on the planet because of the delicate balance of these naturally occurring gases.
Human activity including the use of the internal combustion engine in vehicles, industrial manufacturing, electricity generation through the burning of fossil fuels, the burning of large tracts of forest or grassland, and the methane and nitrous oxide produced by intensive farming all contribute material to this protective blanket more rapidly than occurs naturally. The resulting effect of this increase in the invisible blanket of greenhouse gas is that the sun's light and radiation are not able to escape back through the atmosphere - and the earth retains heat in excess of what maintains climate balance.
When the balance in emissions is disrupted, especially when that disruption happens suddenly in geological terms, severe changes in local and global climate in turn cause changes in conditions for life forms of all kinds: the greenhouse becomes a threat to those inside it. Carbon dioxide, the waste from burning petroleum and other fossil fuels, accounts for 60% of this enhanced greenhouse effect, with the result that the carbon cycle, and exchange of the same carbon that makes life possible on Earth, is distorted, and the air, oceans, and land vegetation all experience severe alteration.36
Levels of atmospheric carbon dioxide have increased 30% since the carbon-fueled Industrial Revolution began two hundred years ago; the concentrations of methane have risen 149% since pre-industrial times, as animal agriculture and human waste landfills have also become industrial.25 The rapid rise in CO2 levels is causing the Earth's temperature to rise more rapidly than existing life forms can adapt. If this rate of warming continues, there will be severe increase in rainfall in some areas, extreme drought in others, bringing with it further shortages in water; agriculture will be effected, and biodiversity will decrease as species lose habitat and find it impossible to adapt rapidly to the vast changes in air, water, and land.
Vast, complex and often subtle changes are difficult for the human imagination to take in, and to take responsibility for. If we look at these changes in more specific terms, the degree of devastation becomes plainer - and our relationship to solutions more understandable:
- Snow cover in the Northern Hemisphere has decreased 10% since 1966.25
- The Arctic Summer melting season increased between 1979 and 1998; the shortest being 57 days in 1979, and the longest being 81 days in 1998. This averages a five-day increase per decade.25
- The Antarctic Peninsula has warmed more than 2°C since the 1940s.25
- A study done by the United States Geological Survey showed that the number of glaciers in Glacier National Park decreased from 150 in 1850, to less than 50 today; they predict that there will be none in 30 years.
- According to the National Center for Atmospheric Research, Earth's dry, arid lands expanded from less than 15% of the total in the 1970s, to 30% by 2002.36
- The warmest 22 years on record have taken place since 1980; six of the highest temperatures have been within the last eight years.1
According to the Intergovernmental Panel for Climate Change (IPCC), the average temperature rose .74 °C (1.3°F) in just the last century.25 This may seem an insignificant measurement, but the list of effects from this seemingly miniscule increase is large. The difference in temperature has already caused sea levels to rise, precipitation patterns to change, resulted in more frequent and dramatic floods and droughts, heat waves, more frequent and severe hurricanes and tornados, glacier retreats, reduced stream flows, species endangerment/extinction, and higher or lower crop yields. Each of these phenomena affects the entire population of the planet, and has an effect on other climate features, whether the effects are observed directly at the moment or not.
These facts mean a lot of trouble for the sustainability of the world and everything on it, including human beings. Resources that were once available to escape the short-term consequences of environmental degradation - more forests, minerals, aquifers over yonder, in an unexploited frontier - are no longer available to rescue us from the depletion of supplies. As population grows and today's have-nots compete with the haves for both consumer goods and the basic essentials of daily life, we must understand both the dangers of counting on the future, and the possibility of improving its prospects. Besides living in the natural environment, humans live in societies, political units, and economies; in persuading people to change for the long-term better scenario we have to consider the impact of climate change on these human communities.
As the glaciers melt, less clean water is available for human use from rivers and watersheds that are glacier-fed, and sources for crop irrigation are lost - worldwide, more than 1.5 billion people currently depend upon glacial sources for water. Much of the American West is habitable at current standards of living only through irrigation and redirected water from glacial sources. At current rates a projected loss of 70% of the snow packs of the Western United States will take place by the middle of the Twenty-First Century. In the Yakima River Valley in Washington State, a 2°C increase in temperature would reduce overall farm income by $92 million, and a 4°C increase would reduce it by $163 million.1 The IPCC predicts an increase of 1.4-5.8°C in this century.
There have been minor climatic changes during recorded history that have had a devastating impact on local agriculture, and even forced emigration from regions of the world. But these changes were small and temporary compared to the changes we are causing with this extraordinary warming of the planet. Since the last ice age 18,000 years ago, the increase in average global temperature has been only 5 degrees Fahrenheit - and one degree of that increase rose in the last century alone. Here are some examples of changes we can expect to observe directly in our lifetime:
- Just a 1°C rise yields 10% less corn, wheat, and rice according to a study conducted in the United States between 1982 and 1998.1
- A study from 618 different countries producing corn, and 444 countries producing rice noted a 17% decrease in crop yields with the same 1°C temperature rise.
- In 2002, record high temperatures brought about severe droughts, causing a world harvest loss of 90 million tons; in 2004 there was a loss of 34 million tons due to drought caused by increased temperatures.1
- The IPCC predicts that sea levels will rise .09 to .88 meters this century due to thermal expansion and melting ice.25
- The World Bank, which provides funds and risk assessment to developing regions, has predicted that there will be a 1 meter rise in sea levels within this century. This seemingly small increase would force millions of Bangladeshis to migrate inland due to flooding; 1/3 of Shanghai would be underwater, the U.S. would lose 3,600 square kilometers of land, including lower parts of Manhattan and Washington D.C. These regions will become not just uninhabitable - their loss will result in the movement of populations, the loss of wealth, and all the instability that goes with this sort of disruption. Think of New Orleans after Hurricane Katrina as a worldwide trend.1
There is no single definitive solution for the problems caused by global warming. There are, however, many serious efforts underway to reduce, stop, or even reverse the effects of human activity that contribute to the phenomenon. The first international effort to combat global warming was the Kyoto Protocol. The Kyoto Protocol is a treaty commitment from signatory countries (excepting developing nations) to reduce their emissions of carbon dioxide and five other greenhouse gases; or, alternatively, to engage in an emissions tailing, which provides economic incentives for emission reduction. One shortcoming of the Kyoto Protocol is that the clause exempting developing nations from the curtailment standards includes China and India, currently second and third in the world for CO2 emissions and the most rapidly developing and populous nations in the world. The United States is the greatest contributor to carbon emissions and has not yet agreed to sign on to the protocol.36
To stabilize climate at its present status, worldwide carbon emissions must be cut by 70%. The European Commission has developed a plan to cut emissions 20% by 2020 and increase the use of renewable resources 12% by 2010. Incentives - beyond just the threat of extinction - are being provided to encourage people to replace old and inefficient refrigerators, switch to high-efficiency light bulbs, and to insulate roofs in order to reduce energy required for heating and cooling. On a grander scale, the EC will add 15,000 megawatts of wind power, increase ethanol production five-fold, and bio-diesel production three-fold. It is predicted that by 2020, wind-generated electricity will satisfy the residential needs of some 195 million European consumers, about half the population of the region. Iceland, rich in geo-thermal and wind capacity and lacking in timber, coal and other carbon sources, is the only country with a strategy for cutting the use of fossil fuels entirely. Today, 93% of homes in Iceland are heated with geothermal energy. They save a combined $100 million per year by not importing oil. Germany has a plan to reduce energy use 37% by 2050, and 43% of the remaining 63% will be from renewable resources. This will result in a 65% reduction of total carbon emissions.1
Americans must participate in efforts to halt and reverse global warming. If a basic understanding of the causes and dangers of rapid climate change is paired with the knowledge of better choices, we can immediately begin the work of saving the planet for future generations. This white paper offers an overview of the current state of the planet, and the alternatives we can employ in slowing and even reversing environmental degradation and warming.
ENERGY USE, SHORTAGES, AND ENVIRONMENTAL IMPACTS
Many of the causes of global warming can be directly attributed to the world's appetite for energy to power the technology that has, somewhat paradoxically, allowed improvements in living conditions for millions in developed regions. The depletion of these conventional energy resources has kept pace with the negative impacts the use of these energy sources have had on the natural environment. By examining the ways we use current sources of energy and their impacts on planetary environmental health, we can better understand how to reduce or remedy the damage. From this understanding, it's a small step to embracing the benefits of alternative energy sources such as solar, wind, geothermal, biofuels, hydroelectric, and the use of hydrogen as an energy source.
Carbon-based fossil fuels have historically been the most widely used resource for our energy needs. Fossil fuels are essentially the dead remains of formerly living things that have become buried under pressure in the soil or mud of river, lake, and ocean bottoms. One of the overall downsides of burning fossil fuels is that only 40% of the matter burned is actually transformed into useable energy, the other 60% escapes as waste heat.4 Various innovations can be applied to conserve this waste: the waste heat can be captured for heating water, which can then be piped for residential and commercial heating during the winter season; carbon dioxide from commercial and residential furnaces can be extracted and stored rather than being emitted into the atmosphere; coal can be converted into hydrogen, to be burned in a gas turbine, and produce only water vapor as waste.
But even maximizing the efficiency of fossil fuel use and mitigating its negative effects will not change the fact that oil and coal supplies will certainly not last forever. Even with maximum efficiency of use and bi-product reduction, we will have to move beyond coal and petroleum, as one can see as we consider the differences of scale in time and cost of renewing energy sources: coal and oil would be fully renewable, but not on a human time scale; other sources of energy may be more conducive to maintaining a quality of life we have come to regard as necessary, while meeting the demands of relatively short human life spans.
Coal is one of humankind's earliest large-scale fuels, a fossil fuel that is non-renewable. Once used for home heating and to fire the factories of industry, in the developed world most coal is now burned to produce electricity; both from this use and from heating and manufacturing use in the developing regions, coal continues from early modern times to be one of the biggest contributors to carbon emissions. In addition to this deleterious effect on the environment, the supply available to be mined is finite and increasingly difficult to access. Coal is the United State's most abundant fossil fuel, and is mined in 27 states, producing more than 1,131million short tons for consumption in 2005. According to the Energy Information Administration around 18,944 million short tons of coal is available for use worldwide as of 2005; 267.6 billion short tons of this in the U.S. alone, which is enough to last about 236 years at today's rate of use.15
Coal burning plants have been slow to utilize the technologies for cleaner and more efficient combustion of coal. Today, a combination of governmental regulation, social pressure, and increased costs of finished coal are resulting in cleaner and more efficient uses of the fuel. Application of these technologies is uneven across geography and industries, and almost non-existent in the developing regions in which energy consumption has been relatively low compared to that of developed industrial nations, but where growth in demand has been and is likely to continue to be exponential.
Coal production is hazardous to those directly involved in the industry, and coal mining requires intensive rehabilitation to the landscape. Historically, large tracts of land were rendered unusable as a result of coal mining and waste. Because relatively basic technology can access coal with minimal education of direct laborers, poor and developing regions are likely to continue to use coal for heating and manufacturing long after cleaner uses of this fuel diminish in richer countries.
Oil, as an adaptable fuel for internal combustion engines, has been a major contributor to the development of modern society, and also to the world's environmental, economic, and political problems. Crude oil is a dark, sticky liquid found in certain rock created by the decomposition of organic matter over millions of years. Rendering this raw material suitable for use in our technology requires energy-consuming and water, air, and soil contaminating refinement processes.
Petroleum geologists say that 95% of the world's oil has already been discovered, and little of the un-tapped remainder lies within the territory of the United States and other developed nations. The International Energy Agency and U.S. Department of Energy have predicted that with current practices, world oil consumption will increase from 84 million barrels per day, to 120 million by 2030.1 Of the twenty-three leading oil producing nations, fifteen have reached their peak production.
- The United States has experienced a 44% decrease in petroleum production since its peak in 1970, with production dropping from 9.6 million barrels per day to only 5.4 barrels in 2004.
- Venezuela has experienced a drop of 31%; and the United Kingdom and Norway both peaked in 1999 and 2000 respectively.
- Saudi Arabia, Russia, Algeria, Angola, China, and Mexico are all pre-peak countries; and Saudi Arabia and Russia were still producing 9 and 11 million barrels of oil per day in 2005.
- Only Canada and Kazakhstan have the potential to significantly increase their oil production.1
Even the untapped sources that lie within the boundaries of developing economies are unlikely to be adequate to emerging demand. For example: If China's economy continues to grow at the current rate of 8%, by 2031 the Chinese will use 99 million barrels of oil per day, but the daily world total production is now only 84 million barrels daily.1
Estimates of how much oil remains in the ground - and how many years of oil-intensive living remain to global society - vary greatly depending on the reporting agency, corporation, or government making the estimate. What is certain is that the majority of the world's petroleum stocks have been discovered, and the majority of oil in already developed oil fields has already been pumped. The most discouraging estimates of the world's remaining oil use is fifty years at current rates of growth in demand; the most optimistic about two hundred years. The complete lack of drillable oil in most of the world, the depletion of oil fields in the most-developed nations, and the growing demand for oil as population and global income increase has resulted in significant tensions between nations and regions, and even armed conflict in defense of access to oil.
The scarcity of any resource has the economic (and, eventually, political) effect of altering the "value" of commodities as the balance of supply changes. For example, there has been a thirteen-fold shift in the wheat/oil exchange rate since 1973 between the U.S. and Saudi Arabia. This has contributed to the largest U.S, trade deficit in history, as well as a record external debt. We sell more grain to oil-rich agriculturally poor nations, but the cost of the oil we buy from them exceeds the increased price of the grain. Saudi Arabia on the other hand, exporting oil and importing grain, benefits economically - and geo-politically.
Natural gas is crude oil's "sister" hydrocarbon fossil fuel, often occurring alongside oil or coal, usable in many of the same applications, but for a long time viewed as a nuisance waste. Like oil and coal, its origin is decayed organic material trapped under rock and turned, by pressure and heat, into concentrated, burnable carbon. It is, for practical human purposes, non-renewable, as millions of years and vast quantities of organic material are necessary for its replenishment. There are some benefits to natural gas over coal or oil: natural gas burns cleaner with fewer emissions, but burning it does emit carbon dioxide.
The main constituent of natural gas is methane, and its combustion releases half as much carbon dioxide as coal or oil. However, this encouraging feature of the gas itself may be offset by the estimates of a 2004 report by the Society of Chemical Industry that leaks within natural gas systems account for 2-4% of the gas consumed. Just this small percentage of waste (methane, including that in natural gas, contributes to the greenhouse blanket) could cause a peak in global warming within twenty-four years, rivaling that from burning coal.4 And in addition to the pollution of atmosphere from this ambient loss, major gas leaks are potentially catastrophic at the local level if not discovered in time.
More than 62.5 million homes worldwide currently use natural gas, mostly as a heat source, accounting for 22% of the total world energy use. Total use of natural gas worldwide breaks down approximately thus: 30% industrial, 26.7% to produce electricity, 21.9% for residential use, 13.9% commercial, 7.4% is used in operation of pipelines and distribution.13
In 2005, the US consumed 22 trillion cubic feet of natural gas. The Energy Information Administration estimates that within the US we have 204 trillion cubic feet of natural gas; world reserves are 6,044 trillion cubic feet. If we can improve the technologies for producing, distributing, and burning natural gas we can extend the life of fossil fuel use - and reduce pollution from burning natural gas - by several decades. Because the United States, and some other areas of the world where oil is in scarce supply, have abundant and underutilized natural gas resources, use of this resource would provide some stability when geopolitical events interrupt access to oil - and when oil eventually becomes too scarce or too expensive to rely upon.
RENEWABLE FUELS, DEVELOPING TECHNOLOGIES
Naturally renewable, alternative energy sources that have potentially infinite availability are not yet widely used, largely because of the expense of changing over from conventional mass-market technologies, or because in their current state of commercial development they do not yet generate energy on the scale conventional applications require. The transitional phase of conversion to renewable energy requires the commitment of policy makers and the general public to the usefulness of renewables - and to demand that current providers make conversion to renewables a priority.
Hydrogen, an abundant, lighter-than-air gas that can be stored as a liquid, can be extracted from coal, oil, or natural gas - and water. That extraction process itself requires energy (and produces, as a by-product, methane just as conventional energy generation does), but once extracted hydrogen burns cleanly and almost without polluting emissions, and has the advantage of three times the burnable energy of gasoline by weight. Less dense than other carbon fuels, hydrogen is light and explosive; it must be stored under very high pressure in metal or carbon fiber containers, and management of its very small molecules requires extraordinary attention to the persistent problem of leaks in storage and pipelines - as is the case with any gaseous substance and liquid hydrocarbons.
The most efficient and easiest way to convert hydrogen into usable power is with the use of a fuel cell, which is essentially a battery with fuel at one electrode, and oxygen at the other, to provide even burning. NASA is currently the top user of hydrogen energy, burning it to propel shuttles into space, and using a fuel cell to power the electric system on the ship. The only by-product of a fuel cell is water, which the astronauts in turn use on board as drinking water.10
But cost of production and inconsistencies in performance and safety has slowed the use of hydrogen for vehicular use. There are only about 200 hybrid-fueled vehicles on the road worldwide, most of them are buses and electric cars using fuel cells. American engineer Geoffrey Ballard offers a theoretical possibility of using direct hydrogen to power cars. He proposes to store it in the gas tanks of vehicles in such a way that it would power the car as well as act as a national energy store. In Ballard's proposal, vehicles would be plugged in to a main grid when not in use, thus recharging while concomitantly becoming a generator of the nation's electricity supply. But at the current rate of improvement, the Energy Information Administration predicts that hydrogen-fueled cars of whatever technology will not be widely available and affordable for the general population until about 2018.
Hydrogen production in the United States today is at 7.8 million metric tons, almost all of it used by industry for refining, treating metals, and processing foods.10 Hydrogen equal to this quantity would be necessary to power twenty million vehicles. The connection between fuel supply - raw materials, in a sense - and demand by available new technologies is a major logistical problem for increasing use of any alternative fuel.
Widespread application of solar technologies would allow us to avoid the scarcity issues of other fuel sources - as long as the sun continues to shine. Sunlight is humanity's first energy source: simply receiving sunlight provides warmth for human dwellings, and sunlight is essential for plant production. Recently humans have learned to harness and control the use of solar energy not just for heating, but as a source of stored energy for some of the same applications for which fossil fuels have been employed. There is special appeal for solar energy in locales that are remote from the energy grid, without recourse to other means of electrical generation. Solar energy is plentiful and has the highest power density of any energy source; it is also pollution free once it is in use, and its harnessing technologies require little maintenance. But the technologies must, nevertheless, be available in sufficient supply for widespread use to be economic and practically accessible to the general public.
Solar heating is the most obvious use for harnessing the sun's power. Solar heating of the home itself depends upon collection of sunlight, and storage of this energy. Heating water with solar can reduce the need of a conventional system by 2/3 in the average household.43
Solar heating systems rely upon three basic elements: thermal collectors, a storage tank, and a circulation loop. An active system uses a pump to circulate water, or another heat transfer liquid; a passive system, or a thermo siphon system uses natural circulation to move water or a heat transfer fluid. These systems are the least expensive, and the most widely used. The manufacture of the systems and transport of them to end-users requires, at this writing, conventional energy sources. But once in place, solar heat and storage provide clean, safe, non-polluting energy with easily updatable entry-level technology.
Solar Generation of Electricity
As sunlight travels through the Earth's atmosphere, the atmosphere absorbs 16% percent of it, and 6% becomes "insolation," surface radiation available for storage as power. The average insolation, or available power is between 125 and 375 watts per square meter. Current technologies permit solar panels to convert only about 15% of this wattage into electricity.
Photovoltaic cells collect and convert sunlight directly into electricity using semiconductors, solids able to conduct electricity between diodes. A simple example of a familiar instrument that relies on photovoltaic cells is the hand-held calculator. According to the International Energy Agency, today's average photovoltaic (PV) module is only 10% -15% efficient; at this efficiency level, 10-12 PV arrays (modules of forty cells, one half-inch by four-inches) can provide enough power for a single household.26
The use of photovoltaics on a larger scale is promising: The World Bank predicts that the solar electricity business will reach $4 trillion within the next thirty years. Currently, PVs tend to be expensive to produce, and there is a growing shortage of silicon, the most widely used semiconductor for production of solar generated electricty. The good news is that production costs are dropping by 3-5% each year and there was a 32% increase in production in 2003. Overall, the world has a capacity of 60% use of solar cells.43
Concentrating Solar Power is a large-scale solar thermal technology that uses configurations of mirrors to concentrate solar heat and then convert this captured energy to generate electricity in a steam generator. These are relatively low in cost and can deliver power in areas or during times of relatively low sunlight, and, though not currently the most widely used systems, are the most efficient solar systems now available.
Another option that would be available for fairly widespread use is solar ponds. These are simple and inexpensive; they are just sealed pools of water that collect and store energy from the sun using different layers of concentrated salt. The top layer is made with low salt content, the middle layer is made with a salt gradient that prevents heat exchange through the water, and the bottom layer contains a high salt content that is designed to reach temperatures of 90°C. The system then uses the heat that is trapped in this bottom layer either to circulate warm air and water, or to drive a generator to produce electricity.
Harnessing the wind is by no means a recent concept - windmills have been used to grind grain, pump water, and drive small turbines for centuries. Small generators have been run on individual windmills in many locales, and some large "wind farms" have demonstrated the feasibility of producing and storing energy for direct use and for contribution to the commercial grid. Today, many people believe that wind is the best option for energy in the future, seeing as it is clean in generation and undoubtedly limitless - even if not always steadily blowing.
The first electricity-generating wind system was developed in 1888 by Charles F. Bruss, but application of such systems was limited at a time when commercial production of conventional fossil fuels was relatively low-cost financially. Wind can be harness to generate electrical power through the conversion of the kinetic energy in wind, by transferring and/or storing that energy. Rotating mechanisms moved by the wind transfer this motion or kinetic energy into direct use by a series of gears, or into storage within wires and battery cells .
There are two basic designs of wind turbines, the familiar "horizontal" windmills with propeller-style blades on high towers; and "vertical" wind generators, with eggbeater-style blades that run from top to bottom on proportionately shorter elevations of wider proportions. Both designs are attached to mechanisms that capture energy and transform it into electrical energy. Large commercial versions of the horizontal turbine may stand twenty stories high and have blades 200 feet in diameter; vertical turbines for commercial use may be 100 feet tall and 50 feet wide; about 95% of functioning commercial wind machines are the more familiar windmill.46
Because, maximally, only about 59% of the energy in a puff of wind can be extracted for use as harnessed energy, wind turbines work most practically when the average wind speed at their site is 10mph or greater. This limits where wind turbines can be placed for commercially distributed energy generation. High altitudes are typically suitable, as are offshore sites and some open plains areas.
According to a report by the United States Department of Energy, the three wind-rich states of North Dakota, Texas, and Kansas could harness enough wind energy to satisfy all the United State's electricity needs. This 1991 report is now considered an understatement of the amount of energy that could be generated from building wind farms in these states alone. The DOE's National Renewable Energy Lab states that, if fully developed, the windy areas of the United States could supply more than 4 times the nation's electricity needs.
At the end of 2005, wind power generation was at 9,100 megawatts, enough to power 2.3 million homes. The year 2006 saw a 25% growth in the use of wind power worldwide; wind now generates 1% of the world's electricity. Globally, that amounts to less than 74,000 megawatts; by the year 2010 the World Wind Energy Association estimates that total will more than double to 160,000 megawatts by 2010. In some European countries, particularly Spain, Germany, and Denmark, 20% of electricity needs are already being met with wind power. The US currently produces 17 billion kilowatts of wind-sourced energy per year, enough to power around 1.6 million homes, accounting for only 0.4% of all electricity used in the country.64
A range of scales of production is available with current wind technology. Small, off-grid wind turbines can produce 250-watts to 50 kilowatts of power, enough to make them attractive and available for uses such as charging batteries on a boat, or powering a dairy farm. At the other end of the scale, large, offshore turbines ranging from 30-50 meters long and 50 - 100 can produce 250 kilowatts to 3.5 to 5 megawatts. We have only begun to explore the uses and applications of wind power at scales between the micro and mega - but interest in wind power seems nearly as infinite as the wind itself; wind energy projects are under development in thirty-six states in this country alone.
Some obstacles to rapid conversion to large-scale use of wind energy include price of production and land consumption. While wind turbines are very low in marginal costs, the up-front costs are large. The offshore placement of turbine farms beyond the view of land dwellers is favorable both aesthetically and for efficiency reasons, but the maintenance of offshore equipment is more costly and difficult than inland installations. The World Wind Energy Association suggests adapting an existing technology to address the conflict between aesthetics and cost of service: platforms called "jack-ups" have been used for offshore oil exploration and drilling; these portable platforms can transport wind turbines offshore to ocean depths of 120 meters, and allow for relocation of the turbines inland for maintenance. But with widespread practice of this technique another problem will have to be addressed: such installations may impede commercial shipping routes by requiring ‘no-go navigation" in the vicinity.
While the aesthetic issue may seem trivial by comparison with the world's need for energy, the installation of 17,000 large wind turbines in Germany alone calls attention to the balance we need to strike with regard to energy need, land use, pollution trade offs (illumination of wind farms is one issue; so is the hazard they may present to migrating birds) and human comfort with visible changes in environment. The United Kingdom and Denmark are installing wind farms on scales relatively larger than those currently installed in the United States, where available wind-rich terrain is more abundant. Whether we can make cultural peace with the charms of this clean and renewable energy may effect our willingness and ability to quickly expand its use.
Just as coal, oil, and natural gas are fossil carbon fuels, carbon-based biofuels can be converted into energy through refinement and burning. Grains, grass, and other biomass can be converted through fermentation or transesterification into compounds suitable for use in internal combustion engines and hybrids. Some advocates believe that biofuels will provide benefits in the form of energy independence and endlessly renewable energy.
Ethanol, biodiesel, butanol and methanol burn with lower carbon emissions than petroleum fuels, and they have the potential to simultaneously boost domestic economy by creating jobs and by keeping money that would otherwise be spent importing petroleum or other fuels within the country of production.
In 2005, biofuel use worldwide was equal to 2% of the world's petroleum use:
- Biodiesel production went up from 251 billion gallons in 2000, to 790 billion in 2005;
- Ethanol production increased from 4.6 billion gallons to 12.2 billion gallons, a 165% increase;
- Methanol and butanol account for a very small proportion of total biofuel use.
Different countries use different crops for biofuel production. The United States uses primarily corn and produces 3.2 billion gallons of ethanol per year, equaling 2% of its fuel needs. Brazil uses sugarcane for ethanol and produces 4 billion gallons per year, which takes care of 40% of its fuel needs. France, the U.K, and Spain use mostly sugar beets, wheat, and barley for ethanol production. The European Union has a goal of producing enough ethanol to meet 5.75% of its auto fuel needs by 2010.1
One of the problems of biofuel production is its vast requirement of agricultural land. In Brazil, for example, half the sugarcane crop is used to produce sugar; the other half is used for ethanol. If Brazil went from using 5.3 million hectares to 8 million they could be self-sufficient as far as auto fuel needs while maintaining their sugar exports. But in addition to the already existing concern about deforestation in the region, sugar cane production is exhaustive of topsoils and the burning of cane fields traditionally used to manage pests and weeds contributes to both erosion and air pollution. In the same way, wheat, corn, and soybean production all cause damage to topsoil through nutrient depletion, erosion, and the chemical herbicides and insecticides used in their production at commercial levels.
Brazil is not alone in facing problems with biofuel production. If the world wanted to and were able to successfully use only biofuels for all transportation needs, personal and commercial, we would need several earths to produce the half-gigaton of biomass needed to accomplish this task (1 gigaton is equal to 1000 million tons). Biofuel critics point out that they are not really the infinitely renewable resource they are popularly portrayed as. Biofuels require agriculture, and the land and water needed to cultivate food crops is increasing at the same time agricultural land is being lost by erosion, salinization, and desertification - especially in developing nations where the pressure for both food and fuels will grow most rapidly in the next hundred years. If ethanol crops compete with food crops in high-poverty regions, the impact on humans from hunger may offset the benefits of cleaner fuels.
A new potential option for ethanol production is to use enzymes to break down cellulose found in switch grass, for what is referred to as "cellulosic" ethanol. Switch grass is a perennial grass that grows in areas vulnerable to erosion, and which may be more efficient as a source of ethanol and bio-diesel than other crops currently grown for the purpose. Cellulosic ethanol from these sources would have an average yield of 1,150 gallons of ethanol per acre; this source would not disrupt food crop yields or destroy forests because the grasses needed to grow these groundcover plant materials can be grown in marginal land not useful for row crops, and even show promise for use in reclaiming land that has been damaged by other agricultural, mining, and industrial practices.1
Balanced inclusion of biofuels in the world's portfolio of available energies will require careful planning and discerning use of land and water resources, as well as improved technology and understanding of energy potential within a variety of plant materials. As legislatures move quickly to mandate biofuel use and to subsidize its production, additional challenges will be confronted to balance the interests of the emerging industry with those of an increasingly interdependent global community.
Geothermal energy is the use of heat from inside the ground (geothermal heat) to generate electricity. Geothermal energy is considered renewable because the heat from Earth's core is unlimited, and in areas dependent upon hot water reservoirs, what is taken out of the ground can be replaced, making it a sustainable energy source. Geothermal fields produce 1/6 of the CO2 that ‘clean' natural-gas-fueled power plants do, and Geothermal produces energy 95% of the time, compared to the 75% availability of a coal plant. Where it is available, geothermal energy is a domestic product with secure access.42
There are three different types of geothermal plants: dry steam, flash, and binary. The dry steam plants remove steam from fractures in the ground and use it to directly drive a turbine, which spins against a generator. Flash plants take hot water out of the ground, allowing it to boil as it rises to the surface; the water is then separated into its steam phase to drive a turbine. Binary plants use hot water flowing through heat exchangers, which boil organic fluid that spins turbines; the leftover condensed steam and geothermal fluid is then injected back into the rock.
Geothermal heat pumps take advantage of the consistent temperature of the top 10 feet of the Earth's surface: 50-60°F (10-16°C). A heat pump consists of pipes buried within ten feet of the surface, a heat exchanger, and ductwork. In winter, heat from the ground goes through the heat exchanger and into the building, warming it; during the summer the heat is pulled out of the building.41
Japan has utilized geothermal energy to satisfy one-third of its electric needs, and in the Philippines geothermal energy is used to generate 27% of its electrical supply. By far the greatest reliance on geothermal use is Iceland, where more than nine out of ten homes are heated by geothermal energy.
Hydropower uses water to power machinery or to make electricity. Turbines and generators are used to convert the kinetic energy of water into electricity, which can then be fed into a grid to power buildings and machinery. There are 3 types of hydropower: hydroelectric, tidal power, and wave power.
Hydroelectric generally makes use of dams to create energy. As of early 2007 hydroelectric power supplies 19% of the world's electricity, almost entirely by the use of running rivers, or damming to create a concentrated effect. A major problem with this type of energy is that it exploits and even drains the world's water supplies. So while it is a clean energy source from the perspective of air emissions, it is not without implications for watersheds, aquifers, and even rainfall.
The second type of hydropower, tidal power, harnesses the tides in bays or estuaries. The moving water of tides is used to turn turbines. However, this method generates electricity in bursts that coincide with tidal cycles of about six hours duration, and has various negative environmental implications for local shorelines, estuaries, and wildlife.
Wave power yields more energy than tides do and the initial results of testing are looking promising. This type of energy would be especially useful for countries that have large coastlines, and rough seas. These conditions increase the possibility of generating electricity in volumes for utility use.
There are three typos of hydropower plants: impoundant, diversion, and pumped storage systems. Impoundant plants are built where rivers are dammed to store water in a reservoir; when the water is released to flow downstream it flows through a turbine at the dam, which activates a generator and creates electricity. Of the United State's 80,000 dams, 2,400 produce power. Diversion, or ‘run-of-river' plants generate power in a similar manner; river water is channeled through a canal or penstock to the turbine. Pumped storage system stores energy by pumping water up from a lower reservoir to an upper reservoir during times of low electricity demand; as demand increases, the water is released to fall through turbines to generate energy, and then the water is pumped back to the upper reservoir to repeat the cycle.
Some advantages of hydropower are that it is clean, renewable, produced domestically, and generally available when needed - though major drought can reduce capacity for local generation. There are disadvantages as well. Fish populations can be affected if they are unable to migrate upstream past impoundant dams, or if they cannot get downstream to the ocean; to avoid the worst of this particular effect, new dams have been designed with fish ladders and deterrent systems, and several older ones have been retrofitted with them to mitigate this effect. Hydropower plants can also impact water quality and flow, and can cause low dissolved oxygen levels in the water that affect plants and animals in the river system. Damming often requires the loss of land and property in huge reservoirs as is the case with the Glen Canyon dam that formed Lake Powell, and the Aswan Dam on the Nile. Erosion of riverbanks because of altered patterns of flow and interruptions in estuarial environments are also common effects of damming.
Canada, Norway, and Sweden currently satisfy half their electric needs with hydropower. In the United States, the Department of Energy actually expects a decline in hydropower generation through 2020 due to" environmental issues, regulatory complexity, and energy economics."47
BIOLOGICAL SYSTEMS AND SPECIES DIVERSITY
Over millions of years changes in the Earth's climate and geology have resulted in changes in the population of life forms that inhabit the planet, both globally and locally. These changes, whether sudden or gradually, result in the displacement or extinction of some species, and in the emergence over time of new and varied plants and animals, from the microscopic to mega. While some species will always be more survival-prone than others, periods of multiple and mass extinction have been relatively rare over the millennia; international scientific organizations have arrived at consensus that the world is now experiencing it sixth major period of extinction, with a loss of species diversity increasing daily.
The loss of biodiversity results from several influences, but with large predators all but eliminated from the human ecosphere, human activity now accounts for or contributes to most species loss. Rapid climate change challenges most species, eliminating specific food sources and habitat, altering migration patterns, and often requiring physiological or habitual adaptation to temperatures for which previous adaptations leave organisms ill-prepared. But short of climate change itself, environmental damage and change caused by human activity put pressure on species - often even before we have identified their existence or the value to our own. Deforestation, desertification, intensive agriculture, environmental poisons, residential and industrial sprawl and mismanagement of water resources also account for the loss of biodiversity on a large scale. More gradual have been the effects of commercial standardization of species, as in the case of animal agriculture, and those of human-sped spread of invasive plants and animals that out-compete native species. Exposure to unfamiliar diseases, and the cross-species spread and mutation of familiar ones weakens organisms, and whole populations can be lost very rapidly.
HABITAT AND BIO-DIVERSITY LOSSES ARE INTER-RELATED
Writing for The Ecologist magazine, Simon Retallack, head of Climate Change at the U.K.'s Institute for Public Policy Research, predicts that if climate change is not quickly mitigated, 40-50% of coastal wetlands around the world could be lost to rising sea levels by the year 2080. These coastal wetlands buffer land from the effects of flood and storm, filter pollution enroute to the world's oceans, and provide habitat for hundreds of species of birds, fish, and other wildlife. Loss of wetlands means loss of clean water, loss of soil to erosion, and a decrease in species that are valuable monetarily, ecologically, and aesthetically. Loss of coastal wetlands is taking place worldwide, with multiple human activities adding to the impact of global warming:
- The United States has lost more than half its original wetlands since the 18th Century, as farmland, housing, industry and waste disposal encroached;
- At current rates, the Unites States loses coastal wetland at the rate of twenty-four square acres annually - equal to a football field every thirty-eight minutes.
- Minnesota alone has lost half its 18.6 million original acres of marsh and wetlands since becoming a state just before the Civil War;
- The tidal mudflats, salt marshes, and sand dunes of the Netherlands, Germany, and Denmark-migration hotspots for several species of migrating birds-are threatened by rising sea levels, pollution and development;
- England has lost 30,000 acres of shoreline to erosion since Roman times;
- The swampy mangrove forests of West Africa, East Asia, Australia, and Papua New Guinea forests play a pivotal role in erosion control, breeding and feeding for many fish, marine, and bird species - they are disappearing alarmingly due to drainage or in-filling in some areas, and submersion by rising sea levels in others.
- The wetlands of the Mediterranean, deltas of the Nile, and the Po River estuary in Italy are threatened by diversion of water, pollution, and erosion.
As global warming accelerates and changes habitat, the distribution of species alters on land and water:
- The arctic and Antarctic habitats of polar bears and some penguins is literally melting away more rapidly than the species can adapt;
- Several species of North American foxes have moved northward as their native area becomes uncomfortably warmer, encroaching on the habitat of the less-numerous Arctic fox;
- Alaskan seabirds are dying as the fish they normally feed on migrate to cooler waters as the surface waters they live in become too warm for them to breed.
Species that are valuable for human food are also impacted: in the North Pacific, salmon populations plummeted in 1997 and 1998 when the temperature of the ocean rose 10.8° Fahrenheit. Some populations moved further north toward the Bering Sea, but numbers overall have not recovered.
Rising sea temperatures are having a detrimental effect on plankton populations. Plankton are tiny plant (phytoplankton) or animal (zooplankton) organisms that act as the base of the marine food chain. A 2006 report stated that warm surface temperatures disrupt the up-drifts from the ocean floor of nutrients upon which phytoplankton rely. Since these phytoplankton make up the foundation of many marine animals' diets, if they starve, so do millions of others. Phytoplankton remove large amounts of CO2 from the atmosphere, so their removal also contributes to global warming that further depletes the plankton themselves.
In the North Sea, zooplankton, such as krill, have migrated to cooler waters, a shift which correlates directly with decline in sand eel and salmon numbers. This decline in turn affects seabirds such as kittiwakes, guillemots, puffins, and razorbills who feed on the sand eels and salmon. A longitudinal study done over a period of fifteen years concluded, in 2004, that half of the CO2 emitted by human activity has been absorbed by the oceans. This has dissolved carbon dioxide has increased the acidity of ocean waters - and this acidity bodes ill for multiple species of marine animal and plant life.
Coral reefs, including the Great Barrier Reef of Australia, are dying as ocean temperatures rise. These agglomerations of living animals and their skeletons live and grow in waters that are 64.4° to 86° Fahrenheit; if the temperature is raised even 1.8° to 3.6° Fahrenheit, the symbiotic algae that provides the coral with nutrients (and, hence, it's bright color) is expelled from within the sheltering calcium which the algae has aided it in producing. In 1998, extreme heat led to thousands of miles worth of coral graveyards in Australia, the Indian Ocean, the Florida Keys, the Caribbean, the Red Sea, and the Bahamas. Incidents such as these have only been observed since 1979; since that time global warming has continued to accelerate.
Coral reefs provide habitat for 25% of the global south's fish stocks, and provide shores from the direct impact of hurricanes and high waves. The loss of marine life and the deterioration of large tracts of reef have an effect on human quality of life, food supplies - and economic wealth: Australia draws $1.5 billion in tourism of its reefs, Florida draws $2.5 billion, and the Caribbean draws in an astounding $140 billion from reef tourism. Compounding the death by global warming is deterioration due to the erosion from coastal rainforest run-off when forests are clear cut or burned. Human short-sightedness in the form of ‘mining' reefs for their mineral content have been responsible for reef destruction in Sri Lanka and elsewhere, as cement manufacturers exploit this resource without regard to its role in the ecosphere. The Intergovernmental Panel on Climate Change and Greenpeace have independently predicted the extinction of coral reefs by the year 2030 if warming and human predation are not halted.
Of the ten million animal species known to humankind, some 300,000 are known to have become extinct within the past fifty years. The looming extinction of hundreds of thousands more can be inferred from the fact that organizations including the World Wildlife Federation calculate staggering levels of endangerment: 25% of mammal species, 34% of fish, 25% of amphibians, 20% of reptiles, and 11% of birds worldwide are already at tenuous levels in the wild - and many will not survive the impacts of rapid climate change, pollution, and human induced habitat loss, no matter how many conventional legislated protections may be imposed on their behalf.
In addition to the flagship or poster-species animals that most easily attract attention, funds, and special protection - the 1600 pandas still living in the wild; the 700 gorillas in their natural habitat, polar bears, penquins, the rhinos, elephants, snow leopards, whales and dolphin and marine turtles - other species less photogenic and less well known are also under pressure. The first extinction attributed entirely to the effects of global warming was the golden toad of Costa Rica. Worldwide, frogs and toads (often referred to as indicator or sentinel species, that serve as an early warning of habitat degradation) have shown deformities and disease that result from ozone depletion, chemical pollution, and global warming; in addition to habitat alteration, climate change has provided ideal conditions for the rapid spread of fungal diseases that threaten more than 1800 species of amphibians - amphibians survived the great extinction that eliminated the dinosaur; whether they will survive the present period of extinction remains to be seen.
A 1997 study from the World Conservation Union showed that of the more than 240,000 plant species 1 in 8 is at risk for extinction; and about 90% of those are endemic to a single small geographic region. Of the top countries at risk are the US, Australia, and South Africa. In Southeast Florida for example, whole native plant communities such as subtropical hardwood hammocks and limestone ridge pineland have been reduced to mere patches since the beginning of suburban sprawl.
In the US, 2/3 of all rare and endangered plant species are close relatives of cultivated species. If we lose these, we lose opportunities for biodiversity in crops, which puts the world at risk of tragic spreads of disease in crop species, like the potato blight in Ireland in the 1840's. That blight was due to genetically uniform potato crops. There are various reasons that crops can become less diversified. Some reasons are extended drought and climate change, but all too often it is simply the decision of a farmer.
3.5 billion people in developing nations rely on plant-based medicine for primary care, and ¼ of prescription drugs in the US and Europe contain active ingredients derived from plants. Worldwide, over-the-counter, plant-based drugs are a $40 billion per year industry; the US retail market for herbal medicines was around $1.5 billion dollars in 1992. The tropical rainforests are estimated to represent about 12% of the world's medically useful compounds, which are used to make around 50 different drugs. Disturbingly though is that less than 1% of the plant species of tropical rainforests have even been screened, yet we continue to destroy them, as well as our chances to develop life-saving medicines.
Invasive species, or species that live and reproduce in areas to which they are not endemic, are one of the biggest management problems in many areas. In 1996, the South African government initiated a program to rid the land of their unwanted, invasive plant species. This program also employed some 40,000 people, helping the economy and quality of life in the country. Of course, some invasive, or exotic species are entirely innate, such as wheat, apples, rice, and tomatoes in North America. However, others like the tamarisk from Asia, which was originally introduced for erosion control has reduced the flow of rivers and disrupted water supplies and animal habitats. The Chinese tallow tree is taking over the ecosystems of Southwestern Texas, and exotic grass species have almost replaced the native grass species in California. A plant species called Kudzu was originally brought to the Southeastern US to be used as ground cover, but has choked the native plants and trees, leaving completely barren land when its leaves fall off during the winter season.
Conservation International estimates that nearly ¾ of the planet's ‘habitable land surface' is either partially or heavily disturbed. Areas protected by legislation or treaty encompass nearly 12 million square kilometers, or only about 8% of the Earth's land surface.
HUMAN DISEASE AND RAPID CLIMATE CHANGE
People living in temperate climates have taken for granted their relatively safe situation epidemiologically. Disease in northern climates can largely be controlled through personal and public hygiene efforts to manage microbes, and the cyclic freezing and thawing of these regions has allowed them to largely avoid illnesses borne by insects and parasites over the past several hundred years.
As the temperature heats up, malaria-carrying mosquitoes are moving to higher ground. In Nairobi, Kenya, 40% of the city's children are infected with malaria, whereas just a few years ago, Nairobi was a malaria-free zone. Weather isn't the only thing affecting the spread of malaria; flood and drought also play a major role. The puddles left after a flood and the stagnant streams of drought are ideal breeding grounds for malaria-bearing mosquitoes.
The risk for malaria has doubled for southern and central Europe in the past 20 years. Worldwide, malaria infection quadrupled overall between 1995 to 2000. There are now million deaths per year and 400 million new cases of illness. Epidemiologists speculate that much of the increased incidence is due to global warming.
Dengue fever, also transmitted by mosquitoes, causes terrible arthritic pain and numerous deaths to the 100 million people who contract it annually; in the 1990's, its range widened from the Carribean and African jungles to include the Americas and northern Australia.
In 1999, the city of New York was introduced to West Nile Virus, an encephalitis-like infection native to northern and western Africa . From an infected human the virus was carried by mosquitoes that survived a historically mild winter. A July heat wave and the swiftness with which pathogens now travel from equator to Metropolis extended the microbes range to 230 species of mosquitoes (and the humans they bite) in 39 states.
Since 1993, the southwestern United States have experienced outbreaks of hantavirus pulmonary syndrome, a flu-like disease carried by little deer mice that causes fever, headache, nausea, joint pain, and a potentially fatal progressive difficulty in breathing due to a build-up of fluid in the lungs. Drought has reduced the number of deer mouse predators, and subsequent heavy rain restored drought-resistant food for the deer mice, such as grasshoppers and nuts. When the mice enter human dwellings in search of food. The airborne virus is transferred by particles of infected rodent urine, saliva, and droppings. Airborne, it travels quickly in urban settings, and is easily spread among the young, elderly, and those with inadequate sanitation - and, as winters become progressively warmer, the virus has had increased northerly range as the mouse's hardiness zone increases.
The World Health Organization's report "Water for Health: Taking Charge" outlines the role that water plays in human health. Only 2.5% of the world's available water is fresh. Approximately 1% of it is contained in lakes, rivers, and channels running underground; the rest is frozen in glaciers and polar ice.
A stunning 40% of the 6 billion people in the world have no acceptable means of sanitation and more than 1 billion draw their water from unsafe sources. There is no better way to spread disease than through poor sanitation. Diarrheal diseases, something that developed nations consider a mere annoyance, remain the leading cause of illness and death in many developing countries. Every year, 2.2 million people die of diarrhea, and 90% of those are children. Bacteria spread by contact with fouled water is the primary source of this suffering.
Trachoma, all but unknown in the developed world, affects poor communities as the leading cause of preventable blindness in the world. The microscopic bacteria Chlamydia trachomatis has blinded millions and impaired the sight of millions more. The disease is entirely preventable if clean water for washing hands is available. Schistosomiasis, caused by a parasite that lives on small snails, has a cycle of infection maintained through fecal and urine contamination of open waters - the same water used for food and bathing.
But there is progress in some places. The work done to fight Guinea worm disease is one example. Guinea worm disease is a disfiguring and disabling disease caused by a large nematode (roundworm) that breeds in open waters like ponds, shallow wells, where people in poorer communities gather their drinking water. In the mid-Twentieth Century, approximately 50 million people in Africa and Asia were infected with the disease, but by improving the quality of drinking water in rural and isolated areas and providing even modest improvements in managing sewage, the number of infected people was down to 96,000 by 1999. Guinea worm disease has been eliminated in Asia and only 13 African nations still see the disease.
However, water projects that just clean up biological wastes and pest infestation cannot prevent all water-related health problems. In Bangladesh, they are facing the largest mass poisoning ever recorded due a water project ‘gone wrong.' Millions of wells dug to improve water quality and quantity were contaminated with arsenic from industrial sources, affecting more than 35 million of Bangladesh's 125 million people. And even in Minnesota and New York, we find ground water polluted by local industries, and questions about long-term safety await answers.
Ironically, just as we are understanding and coming to terms with the techonological and socio-political means of providing cleaner water and better sanitation, we are confronting a period of increased desertification, drying of streams and rivers, more frequent and extreme drought. In many areas of the world, just as we learn to clean up water suitable for drinking and bathing, the availability of water of any kind may be gone with the glaciers that feed the rivers and the aquifers that would fill the wells of the developing world and the municipal pipelines of developed regions.
HUMAN SHELTER AND THE HOME PLANET
The ecological problems facing the world are urgent and of almost incomprehensible scale. The need for societies to cooperate and collaborate in mitigating and reversing the damage to air, soil, and water is not to be underestimated - but neither is the need and potential for individuals to act responsibly. Green practices begin, quite literally, at home. In the United States alone, buildings account for 36% of the total energy use, and 65% of the total electricity use, 30% of greenhouse gas emissions, 30% of raw materials used, 30% of waste output, and 12% of total water use.
Household operations account for one third of common air pollution, and one fifth of toxic air pollution and common water pollution. The running of the home contributes a larger percentage of greenhouse gases per household (35%) than does personal transportation (32%), primarily from electricity use. In fact the largest single home-related drain on the environment is electricity; and at 36 percent, the residential sector is responsible for the largest percentage of total electricity use in the US. Electricity usage for heating and cooling is roughly proportional to square footage; the bigger the home, the bigger the bill.
In our residential choices we are limited by location, climate, and economics, but everyone can make some choices about how we can reduce our carbon footprint through shelter choices. Insofar as is practical, people can live closer to their work and the services we need to decrease our transportation-related contributions to pollution and climate change, control the energy efficiency of shelter by insulating, using the most energy-efficient appliances available (and demanding development of more-efficient ones), building with the most sustainable materials available, utilizing alternative energy sources such as passive solar and co-generation technologies, recycling building, furnishing and consumer materials.
There is a movement in the developed world to define and practice green residential and building standards. The most rapidly developing system of rating green building practices, called Leadership in Energy and Environmental Design (LEED), provides measurements related to location, energy use and sourcing, water conservation, pollutant and toxin reduction, and use of sustainable and renewable materials. These standards can be applied to siting, constructing, furnishing and operating new buildings - but more importantly these practices can be adopted in part for both new and existing buildings.
Practices that move toward LEED standards to reduce carbon impact may be as simple as changing high-energy-use incandescent light bulbs with compact fluorescent bulbs that use less energy and emit less waste heat, insulating windows and doors, using alternative roofing materials, buying Energy Star appliances that improve efficient use of energy, or locating near mass transit that decreases dependency on personal passenger vehicles. Recycling household waste and producing less of it may be the point-of-entry to greener living for one household; co-generating electricity with a small wind turbine may suit another; building a rain garden or choosing native plants instead of conventional lawns may be the best choice for others.
Every choice in one's own shelter makes an impact on quality of life locally and globally. Foregoing the choice of wasteful consumption for mindful use of resources will be essential if we are to preserve the world for future generations - this need not be deprivation, but wiser selection among available options. This is true not only of our housing, but of our use of our larger home, the planet Earth.