Chapter 7: “NEGAWATTS”
By Richard Lance Christie
(Draft date: October 13, 2007)
"Negawatts" is a term coined by Dr. Amory Lovins of the Rocky Mountain Institute to describe energy gained by conservation. He explored the potential for negawatts as a means of meeting national energy needs in his book The Soft Path published in the 1980's.
In the past, the biggest efficiency gains in the U.S. system followed adoption of new federal standards, regulations, tax incentives, and research funding.
According to the American Council for an Energy-Efficient Economy (ACEEE), feasible steps to increase efficiency can reduce U.S. energy use, and related greenhouse-gas emissions, by 30 percent. The Council says this would save the typical American family $650 per year in energy costs. The “2,000-Watt Society” program promoted by the Swiss Federal Institute of Technology claims it is feasible to reduce per-capita energy use in industrialized countries to 2,000 watts per day - a two-thirds energy reduction for Europeans and a five-sixth decrease for spendthrift Americans - without crimping anyone’s standard of living.
David B. Goldstein, director of energy programs at the Natural Resources Defense Council and a recipient of a MacArthur Foundation award for his work on appliance-efficiency standards, says: “We haven’t found a major use of electricity for which there aren't’t great opportunities for savings.” He has written a book, Saving Energy, Growing Jobs which explains the social and economic benefits of a more efficient, sustainable economy that rewards energy efficiency and competition. Princeton professor Dr. Stephen Pacala estimates that it costs 8 to 12 cents to generate and deliver a kilowatt-hour from a new coal-fired power plant, while freeing up that same amount of energy through efficiency costs just 3 cents. Venture capitalist Dan Reicher asks, “Why is it that an energy source that can be deployed at two to four cents a kilowatt-hour isn't’t being deployed - when some of the other things we’re excited about...cost ten times as much?” For example, today’s typical refrigerator uses about one-fourth the energy of a 1972 model to cool a cubic foot of space, but still accounts for 20 percent of total household electricity use. Efficiency standards for appliances generally save consumers $2 to $3 in utility costs for every dollar increase in purchase price.
Without more efficient use of energy, in 2006 the U.S. Energy Information Administration forecast that by 2025 annual energy use in the U.S. will hit 134 trillion megajoules (127 quadrillion BTUs), over a quarter greater than it was in 2005.
Former UC - Berkeley efficiency expert Art Rosenfeld says that if the United States were working at the energy-efficiency level of the early 1970s, we would be spending $700 billion a year more on energy than we are. Investment in energy efficiency has already reduced energy demand and costs. Carl Pope of the Sierra Club estimates that failure to modernize the electricity distribution grid is costing ratepayers $150 billion a year; they are paying to generate electricity that is lost in the grid instead of reaching customers.
Dan Reicher points out that “More than 30 million U.S. homes are currently eligible for the home-weatherization program, which insulates people’s dwellings and can, for a modest investment, reduce home energy use by more than 30 percent....The budget last year for the home weatherization program was $228 million. We’ve done 5.5 million homes in the U.S. in the last 30 years, but we have 25 million more that are eligible for federal and state help. By upgrading a home’s furnace, sealing leaky ducts, fixing windows, and adding insulation, we can cut energy bills by up to 40 percent. By adding energy-efficient appliances and lighting, the savings are even greater. Replacing a 1970s-vintage refrigerator with a new energy-efficient model will cut an average home electricity bill by 10 to 15 percent.”
According to a study by Lawrence Berkeley National Laboratory, energy lost through inefficient residential windows accounts for 2 percent of total U.S. energy consumption. Low-emissivity coatings made from tin or silver oxide reduce winter heat loss and also block entry of summer heat, because they do not allow infrared radiation to pass from whichever side of the film is warmer. Computer-controlled occupancy sensors automatically adjust building lighting based on the amount of natural light available, and adjusts the flow of outside air into the building based on sensing carbon dioxide levels indoors.
The Small Farm Energy Project in the late 1970's sponsored by the Iowa Center for Rural Affairs demonstrated that 24 farmers in northeast Nebraska reduced their energy use by an average of 19 percent by adopting behavioral changes and using farm-based technologies to save and capture energy.
In the May/June 2006 WorldWatch, page 5, Jim Williams observes, “Only a government whose citizens are personally committed to living sustainably will have the moral authority to demand this behavior of the rest of the world.” He and his family rebuilt their house for energy efficiency, changed jobs so they can walk to work, installed solar hot water heating, fly only for family emergency, and reduced their purchases of “useless material goods.” “We have reduced our energy consumption, not just for heating and transportation, but for all the indirect costs of goods and services we receive, to a third of the average American’s, a level that can easily be provided by domestic sources of energy.”
Section 1: Government Energy Conservation Programs
In 2000, California - the world’s sixth largest economy - used 40 percent less energy per capita than the average for Americans. After the Enron-induced energy crisis ended in 2001, California has fashioned a new framework of utility regulations that places even greater emphasis on energy use efficiency. Through 2008, utility companies plan to spend $2 billion - a record for any state - to help California utility customers save energy. According to studies by the California Public Utilities Commission (CPUC), this investment will yield a net gain of $3 billion in economic benefits for the state by producing energy bills. Brian Prusnek of CPUC observes: “In terms of greenhouse gas emissions, that’s the equivalent of taking 650,000 cars off the road. How many other investments yield a 50 percent financial return and reduce pollution?” Under the new “loading order” scheme, when utilities plan for how to meet long-term growth in energy demand, the resource of first resort is efficiency, with renewable energy generating sources next in line. Only if a utility can demonstrate that they cannot meet long-term demand with efficiency and renewable source measures are they allowed to turn to fossil-fuel and nuclear-generated power, and any new plants from which they buy new power must be no dirtier than a combined-cycle natural gas generating plant is currently.
California also developed a strategy for cutting electricity demand known as “demand side management.” Through use of DSM California was able to reduce its energy demand circa 2000 by nearly 5,000 megawatts, equivalent to the output of 10 large power plants. In addition, California decoupled the tie between a utility’s financial health and increases in electricity sales.
Every few years regulators determine how much revenue utilities need to cover authorized costs. They then set electricity rates at a level that allows utilities to recover those costs, based on a forecast of sales. If actual sales are above or below that forecasts, then revenues are “trued up” at the next regulatory cycle: over-collections are given back to customers in the form of reduced rates, and under-collections are eliminated with modest rate increases. The utility companies like the scheme because it stabilizes them financially.
California was the first state to adopt energy standards for appliances. These went into effect in 1977 and were upgraded throughout the 1980s. Florida, Massachusetts, Connecticut, New York, and other states followed suit, sometimes copying the California code verbatim. This shift at the state level led appliance manufacturers to lobby for a national appliance efficiency standard, which President Reagan signed into law in 1987. National refrigerator standards, based on California’s, are today saving more than 130,000 megawatts of electrical generating capacity, a savings of about $17 billion a year in utility costs to users.
California’s efficiency standards for new buildings, introduced in 1978 and known as Title 24, have been replicated all over the world. The code governing new construction in Russia, for example, is modeled on California’s Title 24 and is cutting energy use in new buildings by an estimated 40 percent. China is currently working on instituting California-code-based energy efficiency standards for new construction. California’s efficiency standards resulted from Art Rosenfeld’s work with a team at Lawrence Berkeley National Laboratory which created a computer program that modeled the energy performance of buildings, which they released into the public domain in 1976. Originally known as “Two-Zone,” the current edition is called DOE-2. The work on energy efficiency in buildings led to formation of the LBL’s Center for Building Science, which Rosenfeld headed from 1974 to 1994. In addition to the “Two Zone” building energy efficiency modeling program, the Center developed the low-emissivity window and championed the fluorescent ballast light. The DOE-2's use in building standards are today saving the U.S., conservatively, $10 billion a year in electricity and natural-gas costs. High-frequency ballasts for fluorescent lamps are saving the U.S. around $5 billion worth of electricity a year. Low-emissivity windows are probably saving between $5 and $10 billion a year. The center also led to cities and towns installing thousands of light-emitting diode traffic lights, which use less than half as much electricity as the incandescent lamps they replaced.
When the OPEC oil embargo hit in October, 1973, particle physicist Art Rosenfeld at the Radiation Laboratory of the University of California (now the Lawrence Berkeley National Laboratory) calculated that, if Americans used energy as efficiently as the Japanese or Europeans, the U.S. would have been exporting oil in 1973. Rosenfeld reasoned that the solution to U.S. oil dependence was not to bend Arab regimes to America’s will but to end America’s thralldom by wasting less energy. In 1974, Rosenfeld and like-minded physicists organized a month-long workshop at Princeton to look at energy savings potentials in building design, transportation, the manufacturing sector, and gas and electric utilities. “By the end of the first week, we realized that we had blundered into one of the world’s largest oil and gas fields. The energy was buried, in effect, in the buildings of our cities, the vehicles on our roads, and the machines in our factories.”
B. New York State energy conservation
In 2004 New York passed energy efficiency standards for products that the federal government did not then regulate, such as ceiling fans and commercial freezers. This was part of an eight-state effort to transform the appliance industry. It worked. Once the standards passed, manufacturers lobbied Congress for national standards because it was cheaper to make a single product that could be sold anywhere than to revamp products to meet different requirements in different states.
Section 2: Transportation
Transportation accounts for one third of all U.S. greenhouse gas emissions. A 60 percent improvement in vehicle efficiency by 2020 would cut fuel demand by 2.3 million barrels a day, as much as we now import from the Persian Gulf. Reducing traffic congestion with tolls and improved transit systems could save $63 billion a year in time and fuel conserved.
California-based ZAP (Zero Air Pollution) introduced its first production electric vehicle that incorporates solar power source, the XEBRA XERO, on November 18, 2006. While electric cars are 90 percent less polluting than standard gasoline cars, the XERO has solar panels mounted on its top so that a customer with a short commute can achieve zero air pollution emissions from the energy he drives on by allowing the car to recharge itself while parked in a sunny place.
DaimlerChrysler recently introduced its modular exhaust treatment system - “BLUETEC technology” - which cuts nitrogen oxide and soot output significantly, enabling cars to meet the most stringent U.S. emission standards.
Sandia National Laboratories is working with U.S. engine manufacturers on a new engine combustion process called “homogeneous charge compression ignition.” In theory HCCI can provide both high fuel economy and ultra-low emissions of nitric oxides and particulates. In practice a problem with narrow load range was encountered in engines using the technology, which Sandia reports is being overcome by stratifying the temperature and/or mixture of fuel and air in the combustion chamber. Sandia received a patent on this mixture-stratification technique.
A. Comparing transportation energy efficiencies
Internal combustion engines are only about 10-15% efficient at moving a typical 2-ton vehicle, and less than 1% efficient at moving the mass of the human passenger in that vehicle. However, these figures assume that the fuel for the vehicle magically appears in the tank. In fact, it takes a lot of energy to pump, refine, and transport the fuel, so vehicle efficiency is more accurately measured from oil well or other source to the vehicle drive wheel. As oil becomes increasingly scarce and the environmental costs of burning it are becoming known, we need to develop a means of measuring efficiency that considers the finite nature of earth’s stored energy resources and the effects of fuel burning on the planet’s ability to support life.
Ultimately almost all energy used on earth came from the sun. How about measuring vehicle efficiency from sun to wheel? This gives us a universal standard by which to compare different vehicular technologies in terms of “true” efficiency measured in the same terms.
About 350,000,000 trillion watt-hours of solar energy strike the Earth’s surface annually. It took 3.5 billion years of photosynthesis to create the world oil reserves that contain about 1,000,000 trillion watt-hours of energy. Using direct solar radiation is therefore about 1 quadrillion times more efficient than burning fossil fuel.
Biofuels depend on photosynthetic capture of solar energy by plants to power the synthesis of hydrocarbons. Photosynthesis by plants is at most 1 percent efficient at converting solar energy into carbohydrates when adequate water and nutrients are available. The efficiency of producing biofuels from carbohydrates and then getting the biodiesel fuel into the vehicle tank varies from 10 to 35 percent depending on the process and the distance from manufacture to point of use. Since the vehicle engine and drive train have an efficiency of about 10-15 percent turning fuel energy into torque, the overall efficiency from sun to wheel for biofuels is about 0.01-0.05 percent.
Photovoltaic panels are about 8-16 percent efficient currently in converting solar energy into electricity. The efficiency of solar thermal electric generation can exceed 35 percent. Current battery charge-discharge efficiency varies from 80-95 percent. Electric motors are more than 90 percent efficient at converting electric power energy into torque energy. That results in an overall efficiency from sun to wheel for solar-charged electric vehicles of 3-30 percent. When efficiency is measured from sun to wheel, solar-charged Evs are 60 to 3,000 times more efficient than internal combustion engines burning biofuels.
Section 3: Home heating
A. Floor radiant heating: The Union of Concerned Scientists’ Stephen Young reports the results of converting from a steam boiler supplying radiators to a 92.5 percent-efficient new boiler connected to a radiant floor heating system in his 1860-vintage Washington, D.C. row house. Previously, he faced $500 heating bills with his thermostat set at 59 degrees during the comparatively mild Washington winters. With the floor radiant heating system he used 60 percent less gas with his thermostat set at 69 degrees. The 92.5 percent-efficient boiler cost about a third more than less efficient new boilers, but he calculates he will recover the difference in capital expense in four years from fuel savings.
B. Wood pellets from waste for heating: In October 2006 U.S. Rep. John Salazar (D-CO) opened the first bag of a new type of wood pellets manufactured from slash piles produced by forest thinning and fire-mitigation projects in the forest. The pellets were used to heat the 2,500-square-foot first floor of the Mountain Studies Institute, saving an estimated $1,500 over propane. Forest Energy Corp. of Show Low, AZ, processes pine bark, needles, and core wood together to form a wood pellet suitable for many existing pellet stoves and most new pellet boilers. Conventional wood pellets are made from residue sawdust from lumber mills and furniture factories. The company plans to deliver most of its slash-derived pellets in bulk by truck, eliminating the cost of bags, into a customer’s storage bin or silo from which the pellets would be fed into a modern pellet stove or boiler.