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ENERGY EFFICIENCY ALTERNATIVES

Energy efficiency is assuredly the most effective and economically advantageous means of reducing carbon dioxide emissions and other energy-derived pollutants. Energy efficiency measures in the end use, manufacturing and transmission of electricity replace the need for fossil fuel resources and virtually always produce a net economic benefit, often substantial. Efficiency measures also can reduce the great costs and risks of dependence on oil imports. Many of the products required for efficiency measures can be produced domestically and have the potential for substantial export marketing. Moreover, by improving the efficiency of industrial processes, such measures often result in enhanced competitiveness of domestic production in our global economy.

The potential for reduction of carbon emissions through energy efficiency measures is enormous. It has been calculated that 60% of all primary energy used is lost in various stages of conversion and use, and that over 60% again is lost or wasted at the end-use stage. The IPCC in 1998 made a similar calculation, finding that almost 71% of all primary energy used is wasted. Energy efficiency measures can economically avoid a large percentage of this waste.

Appliance Efficiency

Furnaces, boilers, air conditioners, heat pumps, refrigerators, water heaters, clothes washers and dryers, ranges and dishwashers consume 85% of energy consumption in the residential sector. 65% of energy use in the commercial sector is used for heating, cooling, lighting, water heating, refrigeration and office equipment. In the industrial sector, lighting equipment and electric motors account for more than 75% of electricity consumption. The tasks desired from these appliances can be furnished by much more efficient appliances, often using a fraction of the electricity used by less efficient, widely used models, and offering substantial savings to companies, consumers and society, including reductions of carbon dioxide and other health-damaging pollutants.

Lighting

In countries that have grid electricity, replacement of incandescent light bulbs with compact fluorescent bulbs which last four times longer and use one-quarter as much electricity achieves great savings to the consumer and to society. Task lighting, reflectors and use of daylight also result in significant savings at low or no cost. In many countries, utilities invest in lighting efficiency measures for residential and business customers, sometimes repayable out of the savings from the conversion. Many countries have started to produce the compacts for domestic use and for export, creating important business, revenue and job creation opportunities. Conversion of incandescent street lighting to sodium vapor or other efficient alternatives again creates considerable savings to municipal taxpayers and to the environment, and produces much improved lighting to boot.

In the rural areas of most developing countries, which lack grid electricity, night lighting is provided at high costs and with severe pollution consequences by kerosene. One consequence is that about one-third of the world population uses fuel-based lighting with very significant greenhouse gas emissions and cost consequences. One study found that kerosene accounted for nearly 60% of the total energy requirement for lighting in India's residential sector in 1986 and in Brzel 40% as much energy as reuited for lighting energy in the entire country.

Fuel-based lighting creates substantial amounts of carbon dioxide emissions. The results of a recent study show that between 15 and 88 billion liters of kerosene are consumed each year to provide residential fuel-based lighting in the developing countries. The cost of this energy ranges from $15 to $88 billion per year. This fuel-based lighting results in between 37 and 223 million metric tons of carbon dioxide emission per year. The energy services provided are 1/80th of the level of electric light sources and the lumens of light provided are approximately 1/1000th that enjoyed in households in the industrialized world.

Insulation

Most of the buildings in the developing countries are totally without insulation, resulting in the waste of much of the fuel (usually fossil) which is used to heat and cool them. Many of the older buildings in developed countries also lack adequate insulation. The buildings can be retrofitted with insulation at a payback of just a year or two of the retrofit costs.

Urban Heat Islands

One-sixth of the electricity consumed in the U.S. goes to cool buildings, at an annual cost of $40 billion. In urban areas, the lack of shade for buildings and dark-colored roofs and roads create what is known as Aurban heat islands@ which consume large amounts of air conditioning energy. The planting of deciduous trees on the south side of buildings and painting the buildings in light colors, routinely done in many tropical countries, are low cost/no cost means of achieving substantial savings in the energy used for air conditioning in hot climates. Thus, building owners in Haifa and Tel Aviv are required to whitewash their roofs each spring.

The use of light colored aggregates in highway and road construction materials can also achieve substantial energy savings. The direct savings in air conditioning of the buildings treated are supplemented by an indirect saving from the lowering of temperature in surrounding buildings.

A program promoting urban heat island improvements would achieve multiple carbon dioxide savings B from the absorption of carbon dioxide from the trees and from the reduced use of energy for air conditioning. It is estimated that a tree in Los Angeles will save 3kg of carbon per year by lowering citywide air conditioning requirements plus 15kg per year in building air conditioning savings if planted to shade a building. An urban tree keeps reduces carbon dioxide emissions about 9-times more than a tree in the forest because of the air conditioning it will save in urban areas. A single tree can evaporate 40 gallons of water a day, offsetting the heat equivalent to that produced by 100 100-watt lamps burning eight hours per day.

Cooking Stoves

Much of the cooking in developing countries is done on wood or coal burning stoves, exposing occupants to very concentrated emissions and contributing considerably to carbon dioxide and other pollutant emissions. Inexpensive efficient stoves are available and in use in many places around the world now which both reduce the amount of fuel needed and pollutant emissions.

For example, Kenya has an outstanding cooking stove program, having adapted a Thai Abucket@ ceramic-lined charcoal-burning stove that saves between 20% and 50% of the fuel otherwise used and now costs only $1-3. There are now about 900,000 of these Ajiko@ stoves in Kenya, reaching about 60% of urban households and 20% of rural homes. About 200 local firms produce the stoves. The Kenya program has been adopted in Tanzania, Uganda and Rwanda. China established a National Improved Stove Program in 1992, which has provided over half of China's rural households with improved stoves. China also started to manufacture, install and service the stoves. Some 160 million cooking stoves were upgraded between 1982 and 1998 at a cost of $158 million in government support. The unit cost per stove was $9.

Drinking Water Purification

The recent development of ultraviolet (UV) water purification, if widely adopted, could save the vastly greater energy consumed by existing water filtration and chlorination plants in industrialized societies or the use of fossil fuel or wood to boil water for purification in developing countries. Attendant advantages are that UV processes use no chemicals, impart no taste or odor to water, have no risks of overdose, do not require pressurized water and cost less than the alternatives.

Approximately 1 billion people worldwide use cookstoves to boil their drinking water. This process is reliable, but it demands labor, imposes high economic, environmental and human health costs and is ultimately susceptible to limited fuel availability. It contributes to carbon dioxide emissions both through the combustion of the biomass and the destruction of forests needed to furnish the fuel wood.

UV treatment uses approximately 6,000 times less energy than boiling over a biomass cook stove. UV technology is a rapid disinfection process that acts at the DNA level without heating the water, and thus offers great energy and cost savings potential. It has been estimate that if half the 500 million people in China who use biomass stoves for water purification were to use UV treatment instead, 125 metric tons of carbon dioxide emissions a year would be saved with a potential cost of $0.26 per ton of carbon saved at approximately half the cost of the wood stove technology, not counting environmental externality costs savings.

Recycling

The recycling of household waste products economically saves consumers and municipal taxpayers the costs and pollution of waste incineration. The recycled waste is often convertible into useful products that can create revenues and jobs.

In the industrial and commercial sectors, the recycling of wastes is also economically and environmentally advantageous. For example, the U.S. throws away enough aluminum to rebuild the country's commercial aircraft fleet every three months, even though recycling aluminum takes 95% less energy than manufacturing it. Interface, the world's largest carpet-tile maker, estimates it cuts its materials flow by about tenfold by leasing floor-covering services instead of selling carpet and by remanufacturing old carpet. Land and coalmine gas recovery turns heat-trapping and hazardous methane emissions into a voluble fuel that also displaces fossil fueled power plants.

Transmission & Power Plant Efficiency

In many developing countries, the transmission and distribution systems are inadequate, causing large losses of the power generated and also resulting in frequent blackouts or brownouts that are very costly to businesses. Even in developed countries, these systems are often neglected, resulting in outages at times of system stress -- as with the blackout in New York City in a heat wave last summer. Leaky transmission systems cause unnecessary and costly pollution emissions. Upgrading inadequate transmission or distribution systems should be a high priority in these cases. Usually, these costs are borne by the utility company and paid for in the electricity charges, but legislation and financing assistance may be necessary to effectuate these efficiencies in some developing countries.

Distributed resources such as energy efficiency measures, fuel cells and photovoltaics are often economic alternatives to expansion or upgrades of transmission and distribution systems. Because of their proximity to customer loads, distributed systems can offer improved reliability, as well as carbon dioxide emission reductions, particularly efficient compared with the typical transmission losses of about 10% of central plant generated power.

Most power plants in the U.S. and around the world also are grievously inefficient, converting most of their fuel into waste heat rather than power production. While the U.S. average power plant efficiency has increased from about 23% in 1949 to 32% in 1996 due to the introduction of 52% efficient combined cycle natural gas power plants, if all plants were that efficient, power sector carbon dioxide emissions in 2010 would decline about 30%, cutting U.S. carbon emissions by about 190 MMT. If this generation all came from natural gas plants, carbon emissions would decline by a further 32% (215 MMT).

Industrial Efficiency

Electric motors consume more than half of the electricity in the U.S. and almost 70% of manufacturing sector electricity. Replacement of standard electric motors with smaller variable speed drive motors (as with the gear shift in a vehicle) and matching the motor output to the load, produces large electricity and pollution savings and economic benefits. It has been estimated that variable speed electric motors would result in short-term carbon emission reductions of nearly 10 million tons per year in the U.S., nearly 8 million tons in Japan and over 14 million tons in the European Community. Technological improvements also have permitted manufacture of much more efficient motors.

Industry can also benefit itself and reduce carbon emissions by relamping, replacing their incandescent lights with compact fluorescents, reflectors and task lighting.

The biggest industrial energy savings, though, frequently occur in improving the efficiency of industrial processes themselves, e.g. using continuous casting of steel and utilizing waste products for electricity and heat generation, as is often done in paper, lumber and plywood manufacturing in the United States. The U.S. chemical industry saved nearly half its energy per unit of product from 1973-1990 by plugging steam leaks, installing insulation and recovering lost heat. These kinds of improvements can usually be financed through commercial loans repayable from the savings achieved. Some U.S. utilities do industrial efficiency audits, provide technical assistance and participate in the financing of efficiency improvements.

The industrial sector in the U.S. accounted for about 36 quads of primary energy use in 1997, 39% of U.S. energy consumption, with manufacturing in six sectors dominating (petroleum refining, chemicals, primary metals, paper and pulp products, food products, and stone, clay and glass products). There is a great potential for cost-effective improvement. For example, an in-depth analysis of 49 specific energy efficiency technologies for the iron and steel industry in 1999 found a total cost-effective energy savings potential of 18%.

Combined Heat and Power (Cogeneration)

Utilization of the waste heat from electricity generation for industrial or district heating purposes converts as much as 90% of fuel input into useful energy, compared to 30-35% for a conventional power plant, thus saving significant amounts of fuel and pollution. Conversely, some manufacturing facilities that produce substantial high temperature fluid or steam wastes have used this waste heat for electricity production. Roughly 52 GW of combined heat and power (CHP) was installed in the U.S. as of 1998, providing about 9% of total electricity production. Europe is far ahead of the U.S. in CHP installation, exceeding 30% in the Scandinavian countries and widely being used in the climate strategies of the U.K., Denmark, Sweden, the Netherlands and Germany.

There is enormous potential to expand the use of CHP. For example, the chemicals industry uses only about 30% of its CHP potential and has used only 10% of useable sites. A CHP plant in Stockholm has a net overall efficiency of 86% compared to an average efficiency of just 36% for non-CHP plants in the European Union.

All U.S. conventional power plants together convert only one-third of their fuel into electricity, thus wasting two-thirds as waste heat, which is equivalent to the total energy use of Japan. The Trigen Corporation's cogeneration installation increases system efficiency 2.8 times, harnessing 90-91% of the fuel's energy content, providing electricity costing only .5-2 cents/kWh. Fully adopting this one innovation would profitably reduce total carbon dioxide emissions of the U.S. by about 23%. Selling waste heat from industrial processes to others within affordable distances could cost-effectively save about 45% of Japanese and 30% of U.S. industrial energy, or 11% of U.S. total energy.

However, a variety of barriers including hostile utility policies, excessively onerous environmental permitting requirements, lack of regulatory recognition of CHP benefits and unfavorable tax treatment, limit CHP growth in the U.S. It has been estimated that legislative and regulatory action to remove these barriers could result in an additional 50 GW of installed CHP by 2010 and 144 GW by 2020 in the U.S., with a net savings that pays back the first cost in 4-5 years on average. These policy changes are estimated to achieve carbon reductions of about 27 million tons/year in the industrial sector and 7 million tons in other sectors by 2010.

District Heating

District Heating involves the use of a single heating generator to warm and cool multiple homes in a community. Considerable energy can be saved in defined or newly planned communities by using district heating instead of less efficient heating units for each building or each dwelling unit in the community. District heating is widely used in Europe, particularly in the Scandinavian countries.

Transportation Efficiencies

Cars and light trucks currently account for 56% of transportation energy use. The efficiency of vehicles can be greatly improved through using lighter weight materials and smaller vehicles, reducing wind resistance, improving tire performance and improving the combustion efficiency of engines.

New vehicle propulsion systems are being adopted and designed which can greatly reduce or avoid altogether the use of fossil fuels, namely: electric vehicles with regenerative braking systems; electric/hybrid vehicles that combine electric motors with small, more efficient internal combustion engines; fuel cell-driven vehicles utilizing hydrogen as their fuel; and vehicles propelled by propane gas or ethanol. Toyota is now mass-producing the Prius hybrid car in Japan. Toyoto and Honda are planning to introduce in the U.S. market their two mass-produced electric hybrid vehicles with 50-75% improved fuel efficiency in 2000. Plants for the manufacture of cellulosic ethanol for use as a vehicle fuel or additive are being constructed in a number of U.S. states including Louisiana, California and New York. Argentina established a program in 1984, which has resulted in there now being 450,000 compressed natural gas vehicles in use there.

Many of these new transportation technologies are now being used around the world, particularly in busses and for automobile fleets. The use of natural gas busses has been adopted for Flanders and Brussels in Belgium, Denmark, France and Hungary (which is replacing its old diesel engines with new compressed natural gas for all its buses in Budapest). Brazil has pioneered in growing energy crops for conversion to ethanol as a vehicle fuel. Brazil initially subsidized the manufacture of ethanol adapted vehicles (the subsidies have since been eliminated). This program has avoided the need and costs of major imports of gasoline and has significantly reduced automobile-derived pollution.

Other significant measures to reduce transportation energy use include: land use planning to avoid urban/suburban sprawl that requires the use of vehicles for access to essential services ; promotion of mass transportation facilities that are much more energy efficient than vehicles; promotion of car pooling; van transport to work; and HOV lanes restricted to multi-passenger occupied vehicles on highways; elimination of free parking and imposition of parking fees at business and institutions; and promotion of pedestrian and bicycle paths, bicycle parking facilities, and urban bicycle lanes.

# # #

Energy efficiency measures almost always result in savings to the producer, the consumer and society. They are usually inexpensive compared to new power construction and are capable of financing out of the savings achieved. For developing countries, the initial installation of energy efficient products and processes enables them to leapfrog to use of the superior technologies, thus avoiding the experience of most developed countries in having to convert inefficient products or processes to efficient ones, incurring a double cost and, while the inefficient products are in use, incurring electricity and environmental costs arising from their use.

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