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Published December 11, 2005 in General Science
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Nuclear
Nuclear power is being shunned. It’s not surprising, after the serious accident at Chernobyl in 1986 that made the Russian city’s name synonymous with disaster. The potential exists for more of the same and many countries have given up on nuclear power altogether.
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But in other countries, they’ve been able to make it work. In France, for instance, about 75 percent of electricity is generated from nuclear power. Worldwide, it provides 17% of our energy. The US has not brought a new plant online since 1996 yet still generates 788.6 billion kilowatt-hours (KWh) yearly – almost 20% of the US total – accident free.
Nuclear power is like a handgun. It’s the people handling it who are dangerous. But there is one big difference: with a handgun, you shoot a few people at most. A reactor accident could wipe several hundred square miles – permanently.
But all technologies start out crawling before they can walk or even run. The nuclear scientists have been working on the safety problems and already may have solved them.
Danger aside, what makes nuclear power attractive? It’s competitive or cheaper than other forms of power generation. It’s easy to build compact plants that generate hundreds if not thousands of megawatts – something wind and solar can never hope to match. See the chart below to compare energy generation costs.
[Safe Nuclear Power and Green Hydrogen Fuel, Pic 1]
Image source: http://www.uic.com.au/nip08.htm
Compared with coal, still used to produce 50% of the US electricity needs, nuclear is clean. It creates no greenhouse gases. Its waste, although highly toxic, is compact and when handled correctly, safe.
Uranium, the fuel reactors use, is widely available in the continental US and Canada. Australia has the largest known reserves. This makes it unlikely rouge states can affect supply. Stable supply means lower long-term costs – especially when compared with oil and gas fired plants which are now producing about 20% of US electricity.
Reactor designs such as the Canadian CANDU can be very safe and less expensive to build than most reactors in use today. One drawback to this design, unfortunately, is its ability to produce weapons grade plutonium as a byproduct. On the plus side, it can use unenriched uranium – about .07% uranium 235. Regular plants require between 2% and 7% uranium 235 in reactor fuel to run properly.
Physicists and engineers at Beijing's Tsinghua University have made the first great leap forward in a quarter century, building a new nuclear power facility: a pebble-bed reactor (PBR) – sometimes also known as a Pebble Bed Modular Reactor (PBMR). This reactor is small enough to be assembled from mass-produced parts and cheap enough for emerging economies. Its safety is a matter of physics, not operator skill or reinforced concrete. This reactor is meltdown-proof.
What makes it so safe is the fuel: instead of conventional fuel rods made of enriched uranium, PBRs use small, pyrolytic graphite coated pebbles with uranium cores. As a PBR reactor gets hotter, the rapid motion of atoms in the fuel decreases probability of neutron capture by U-235 atoms. This effect is known as Doppler Broadening. Nuclei of heated uranium move more rapidly in random directions generating a wider range of neutron speeds. U-238, the isotope which makes up most of the uranium in the reactor, is much more likely to absorb the faster moving neutrons. This reduces the number of neutrons available to spark U-235 fission. This, in turn, lowers heat output. This built-in negative feedback places a temperature limit on the fuel without operator intervention.
PBRs use high-pressure helium gas, not water, for cooling. Reactors have been “run dry” – without cooling gas. Result: they simply stabilize at a given temperature – lower than the pebbles’ shell melting point. No meltdown can occur.
[Safe Nuclear Power and Green Hydrogen Fuel, Pic 2]
PBR from www.pbmr.co.za
South Africa may have the most modern PBR on the drawing board. With the help of German scientists – acknowledged leaders in the field - they have planned to build several reactors within the next five years. Images in this article come from their design.
The reactor core is a bin of uranium fuel pebbles. Each tennis ball-sized pebble is rotated and/or checked for reactivity by removing them from the bottom of the funnel shaped reactor core. Spent pebbles are replaced by adding new ones at the top of the stack. Used ones that are still reactive also go to the top of the bin. The reactor can be re-fueled without stopping power production – not possible in conventional rod reactors which requires a full shut down.
Pebbles, because of their round nature, allow the cooling gas to be introduced at the bottom and pass freely through the stack. The heated gas is removed to perform work like spinning a turbine to generate electricity then recycled in a closed loop back to the reactor core.
PBRs use helium, which has high thermal conductivity and inertness (read: fireproof and noncorrosive) for cooling. This makes them more efficient at capturing heat energy from nuclear reactions than standard reactor designs. The ratio of electrical output to thermal output is about 50%.
[Safe Nuclear Power and Green Hydrogen Fuel, Pic 3]
Reactor Interior – pebbles in red: www.eskom.co.za/ nuclear_energy/ pebble_bed/ pebble_bed.html
The high-temperature gas design also has a silver lining – it can produce hydrogen. Think about that – fuel cell vehicles need expensive-to-produce hydrogen to run on – this reactor could make hydrogen as a byproduct.
Generation of hydrogen has been the biggest stumbling block to it adoption as a clean fuel. Hydrogen, found primarily in water, is expensive to extract as a gas. While the technical problems of handling, storage and use as fuel are largely solved, the high energy cost to produce hydrogen has made it an energy transport medium, not a source.
These new reactors run at high temperatures which are perfect for cracking abundant water or helium gas into hydrogen which can then be used as a green fuel – burning hydrogen just produces water vapor.
PBRs could produce cheap hydrogen that could be piped to areas of need or used in the local communities.
Plant sites are much smaller than traditional nuclear power plants. Their modular design allows for smaller plants that can grow with needs. A single PBR reactor would consist of one main building covering an area of about 1,300 square meters – less than half a football field. It would be about 42m high (6 stories), some of it below ground level. Billion dollar steel reinforced concrete containment vessels are not required – any coolant leak would be in the form of nonradioactive helium gas which would quickly disperse with out causing any ill effects.
[Safe Nuclear Power and Green Hydrogen Fuel, Pic 4]
Internal functioning with cooling diagram: www.eskom.co.za/nuclear_energy/pebble_bed/pebble_bed.html
[Safe Nuclear Power and Green Hydrogen Fuel, Pic 5]
Fuel Spheres: www.eskom.co.za/nuclear_energy/pebble_bed/pebble_bed.html
Each PBR would produce between 100 and 200 MW – small, in comparison to light and heavy water reactors which typically product around 1,000 MW. But they could easily be scaled up by adding reactors.
Ten PBR reactors producing 1,100 MW would occupy an area of no more than three football fields. Each PBR could serve about 30,000 to 40,000 homes.
Control rooms - much simpler than standard ones - would have a few PCs and extra monitors instead of banks of valves and dials. Each control room could monitor and manage up to 10 reactors.
One of the key features to this technology, especially important in China where energy demand is exploding, is its modular nature. While conventional reactors in operation today are all one of a kind – although many are based on the same designs – PBR reactors could de built with standard rail-movable components. When a new power plant is needed, they simply load the parts on a train with a construction crew and can have it delivering power in short order. Traditional plants in the US were sunk principally by long construction times and cost overruns, not environmental regulations.
Nuclear waste disposal has become a hot-button issue. Standard nuclear waste is very radioactive for 10,000 years or more. It must be transported to and stored in special containment facilities – normally underground. It can also be reprocessed but this is costly and technically difficult. There are only 3 reprocessing facilities worldwide: Thorpe in England, Cogema in France and Myakrt1 Chemical Combine in Russia. Far away from most of the world that needs clean, inexpensive power.
Fuel pebbles have 4 caps of containment built in. Many authorities consider pebbled radioactive waste stable enough it can be safely disposed of in geological storage – without any additional shielding or protection. Even in tests where pebbles were exposed to very high heat without coolant for long periods, they showed no outward damage. If one did manage to break a pebble it would only release one tiny (0.05mm) uranium dioxide particle. This particle is too heavy to be wind borne and so could not be blown into other areas like the fallout from the explosion at Chernobyl.
PBR proponents state they plan to store all waste products on the plant site – avoiding costly and dangerous radioactive material movement.
Even with the long term radioactivity and highly toxic nature of nuclear waste, some environmentalists are voicing support for nuclear energy.
James Lovelock, well known green activist and creator of the Gaia hypothesis that Earth is a single self-regulating organism, published a plea to phase out fossil fuels. Nuclear power, he argued, is the best short term hope for averting climatic catastrophe:
"Opposition to nuclear energy is based on irrational fear fed by Hollywood-style fiction, the Green lobbies, and the media. … Even if they were right about its dangers - and they are not - its worldwide use as our main source of energy would pose an insignificant threat compared with the dangers of intolerable and lethal heat waves and sea levels rising to drown every coastal city of the world. We have no time to experiment with visionary energy sources; civilization is in imminent danger and has to use nuclear, the one safe, available energy source, now, or suffer the pain soon to be inflicted by our outraged planet." - From the London Independent – May, 2004
Nuclear power, shunned after so many years, may be ready for resurgence. For some countries, like China, it may offer the only hope to meet its energy needs of its billion plus population in the 21st century. Indeed, they already have the first 10MW test reactor up and running.
By Philip Dunn, Copyright 2005 PhysOrg.com
Relevant stories
* British debate use of nuclear power , January 17, 2006
* Duke Power may build nuclear power plants , October 27, 2005
* Oak Ridge lab reactor to return to service , May 09, 2006
* University to dismantle nuclear reactor , April 06, 2006
* China claims progress in fusion, says experimental reactor this year , June 02, 2006
* Bubbly Channels , June 30, 2005
* First Near UV Laser Diode Developed In China , May 23, 2005
* Scientists Spruce Up Nation's Oldest Nukes , 22 hours ago
There is a discussion of this news at PhysOrgForum entitled: Abundant, cheap, safe nuclear power. And no drawbacks.
There are 44 replies in that topic. The last post was on 8-Jun-2006
The first 5 posts are :
On 11-Dec-2005 by blazes
http://www.physorg.com/news8956.html
Sounds like a Tom Swift invention to me.
Sorry, any rosy article that says there is no danger sets of alarm bells as a sell job. What if oxygen gets in, or the pebbles crack in the heat exposing their carbon, etc? What about the security issue of storing radioactive waste on site, or burying it? What if there is a hydrogen explosion?
you can"t just say "yeah, it"s completely safe." You need to go through all the possibilities.
On 11-Dec-2005 by Zephir
Such the technology is always safe, just the peoples are dangerous.... wink.gif
On 11-Dec-2005 by The Unabageler
zephir, I suggest you do a little homework yourself and you'd see that they have indeed gone through all these scenarios. Also, it's helium that is used for cooling not hydrogen, so there is not risk of hydrogen explosion inside the reactor at all. The design of the pebbles prevents a critical mass forming that would cause a nuclear explosion, and the equilibrium temperature of the pebble system is a thousand degrees or so below the melting point of the graphite casings.
One thing the article doesn't point out is that the environment around the PBR housing itself is significantly less radioactive than a traditional fuel rod reactor because the graphite absorbs most of the neutrons before they reach the reactor housing.
On 11-Dec-2005 by GRLCowan
Nuclear power is not being shunned. If it were, that would be very odd. The potential for more Chernobyls does not exist, and never existed outside the former Soviet Union, because in 1950 Dr. Edward Teller foresaw in perfect detail how such a reactor might fail, and made sure from then on no such thing could be licensed in the west. When the US submarine San Francisco rammed a seamount at, I guess, 50 miles per hour a submariner died and many were injured, but the reactor suffered no harm, did none, and got all the survivors home.
Philip Dunn probably thinks he wrote a favorable article on the pebble-bed reactor, but seems not to be aware how much "general knowledge" about conventional reactors, stuff he thinks must be in some textbook somewhere, is actually civil servants' rationalization of their profits from fossil fuels that they cannot hope to make from 100-times-cheaper uranium. Lies, in short.
Contradicting every such display of credulity, as I did above for those in his first paragraph, would take too long.
Many potential faults for the PBMR have, of course, been analysed. Oxygen might get in some considerable time after the pressurized helium had all got out, and so was no longer exerting pressure to block inward leakage of any kind, but dense graphite burns slowly, and there are silicon carbide layers that burn more slowly still (they self-protect with SiO2).
--- Graham Cowan, former Ontario, Canada hydrogen fan
boron as energy carrier: real-car range, nuclear cachet
On 11-Dec-2005 by Dr.K.S.Parthasarathy
There is an error in the following sentence in the article
"On the plus side, it can use unenriched uranium – about .07% uranium 235. Regular plants require between 2% and 7% uranium 235 in reactor fuel to run properly"
It is probably a typo! Natural uranium contains0.7% uranium 235 and not 0.007%
K.S.Parthasarathy
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Nuclear reactor
From Wikipedia, the free encyclopedia
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Core of a small nuclear reactor used for research.
Enlarge
Core of a small nuclear reactor used for research.
A nuclear power station. The nuclear reactors are inside the two cylindrical containment buildings in the foreground—behind are the cooling towers (venting water vapor).
Enlarge
A nuclear power station. The nuclear reactors are inside the two cylindrical containment buildings in the foreground—behind are the cooling towers (venting water vapor).
A nuclear reactor is a device in which nuclear chain reactions are initiated, controlled, and sustained at a steady rate (as opposed to a nuclear explosion, where the chain reaction occurs in a split second).
Nuclear reactors are used for many purposes. The most significant current use is for the generation of electrical power (see nuclear power). Research reactors are used for radioisotope production and for beamline experiments with free neutrons. Historically, the first use of nuclear reactors was the production of plutonium for nuclear weapons. Another military use is submarine / ship propulsion.
Currently all commercial nuclear reactors are based on nuclear fission, and are considered problematic by some for their safety and health risks. Conversely, some consider nuclear power to be a safe and pollution-free method of generating electricity. Fusion power is an experimental technology based on nuclear fusion instead of fission. There are other devices in which nuclear reactions occur in a controlled fashion, including radioisotope thermoelectric generators and atomic batteries, which generate heat and power by exploiting passive radioactive decay, as well as Farnsworth-Hirsch fusors, in which controlled nuclear fusion is used to produce neutron radiation.
Contents
* 1 Applications
* 2 History
* 3 The future of the industry
* 4 Types of reactors
o 4.1 Current families of reactors
o 4.2 Obsolete types still in service
o 4.3 Other types of reactors
o 4.4 Advanced reactors
o 4.5 Generation IV reactors
* 5 Nuclear fuel cycle
o 5.1 Fueling of nuclear reactors
o 5.2 Waste management
* 6 Natural nuclear reactors
* 7 See also
* 8 References
* 9 External links
[edit]
Applications
* Nuclear power:
o Heat for electricity generation
o Heat for domestic and industrial heating
o Desalination
* Nuclear propulsion:
o Nuclear marine propulsion
o Proposed nuclear thermal rockets
* Transmutation of elements:
o Production of plutonium, often for use in nuclear weapons
o Creating various radioactive isotopes, such as americium for use in smoke detectors, and cobalt-60, molybdenum-99 and others, used for imaging and medical treatment
* Research applications including:
o Providing a source of neutron and positron radiation (e.g. Neutron Activation Analysis and Potassium-argon dating)
o Development of nuclear technology
[edit]
History
An image from the Fermi-Szilárd "neutronic reactor" patent.
Enlarge
An image from the Fermi-Szilárd "neutronic reactor" patent.
Although mankind has only tamed nuclear power recently, the first nuclear reactors were naturally occurring. Fifteen natural fission reactors have so far been found in three separate ore deposits at the Oklo mine in Gabon, West Africa. First discovered in 1972 by French physicist Francis Perrin, they are collectively known as the Oklo Fossil Reactors. These reactors ran for approximately 150 million years, averaging 100 kW of power output during that time. The concept of a natural nuclear reactor was theorized as early as 1956 by Paul Kuroda at the University of Arkansas [1]
Enrico Fermi and Leó Szilárd, while both were at the University of Chicago, were the first to build a nuclear pile and demonstrate a controlled chain reaction on December 2, 1942. In 1955 they shared U.S. Patent 2,708,656 for the nuclear reactor.
The first nuclear reactors were used to generate plutonium for nuclear weapons. Additional reactors were used in the navy (see United States Naval reactor) to propel submarines and aircraft carriers. In the mid-1950s, both the Soviet Union and western countries were expanding their nuclear research to include non-military uses of the atom. However, as with the military program, much of the non-military work was done in secret.
On December 20, 1951, electric power from a nuclear powered generator was produced for the first time at Experimental Breeder Reactor-I (EBR-1) located near Arco, Idaho. On June 26, 1954, at 5:30 pm, the world's first nuclear power plant to generate electricity began operations at Obninsk, Kaluga Oblast, USSR. It produced 5 megawatts, enough to power 2,000 homes. [2][3].
Calder Hall unit 1, the world's first commercial scale nuclear power station.
Enlarge
Calder Hall unit 1, the world's first commercial scale nuclear power station.
The world's first commercial scale nuclear power station, Calder Hall, began generation on October 17, 1956 [4] Another early power reactor was the Shippingport Reactor in Pennsylvania (1957).
Even before the 1979 Three Mile Island accident, new orders for nuclear plants in the U.S. had ceased for economic reasons primarily related to greatly extended construction times. As of 2004, no new nuclear plants have been ordered in the USA since 1978 [5], although that may change by 2010 (see Future of the industry below).
Unlike the Three Mile Island accident, the 1986 Chernobyl accident did not increase regulations affecting Western reactors. This was because the Chernobyl reactors were known to be an unsafe design, using the RBMK, without containment buildings and operated unsafely, and the West had little to learn from them [6]. There was however political fallout: Italy held a referendum the next year in 1987[7], the results of which led to a shutdown of the country's four nuclear power plants.
In 1992 the Turkey Point Nuclear Generating Station was hit directly by Hurricane Andrew. Over $90 million of damage was done, largely to a water tank and to a smokestack of one of the fossil-fueled units on-site, but the containment buildings were undamaged [8][9].
The first organization to develop utilitarian nuclear power, the U.S. Navy, is the only organization worldwide with a totally clean record. This is perhaps because of the stringent demands of Admiral Hyman G. Rickover, who was the driving force behind nuclear marine propulsion. The U.S. Navy has operated more nuclear reactors than any other entity, other than the Soviet Navy, with no publicly known major incidents. Two U.S. nuclear submarines, USS Scorpion and Thresher, have been lost at sea, though for reasons not related to their reactors, and their wrecks are situated such that the risk of nuclear pollution is considered low.
[edit]
The future of the industry
As of 2006, Watts Bar 1, which came on-line in 1997, was the last U.S. commercial nuclear reactor to go on-line. This is often quoted as evidence of a successful worldwide campaign for nuclear power phase-out. However, political resistance to nuclear power has only ever been successful in parts of Europe, in New Zealand, in the Philippines, and in the United States. Even in the US and throughout Europe, investment in research and in the nuclear fuel cycle has continued, and some experts predict that electricity shortages, fossil fuel price increases and concern over greenhouse gas emissions will renew the demand for nuclear power plants.
Many countries remain active in developing nuclear power, including Japan, China and India, all actively developing both fast and thermal technology, South Korea and the United States, developing thermal technology only, and South Africa and China, developing versions of the Pebble Bed Modular Reactor (PBMR). Finland and France actively pursue nuclear programs; Finland has a new European Pressurized Reactor under construction by Areva. Japan has an active nuclear construction program with new units brought on-line in 2005. In the U.S., three consortia responded in 2004 to the U.S. Department of Energy's solicitation under the Nuclear Power 2010 Program and were awarded matching funds - the Energy Policy Act of 2005 authorized subsidies for up to six new reactors, and authorized the Department of Energy to build a reactor based on the Generation IV Very-High-Temperature Reactor concept to produce both electricity and hydrogen. As of the early 21st century, nuclear power is of particular interest to both China and India to serve their rapidly growing economies - both are developing fast breeder reactors. See also future energy development. In the energy policy of the United Kingdom it is recognized that there is a likely future energy supply shortfall, which may have to be filled by either new nuclear plant construction or maintaining existing plants beyond their programmed lifetime.
On September 22, 2005 it was announced that two sites in the U.S. had been selected to receive new power reactors (exclusive of the new power reactor scheduled for INL) - see Nuclear Power 2010 Program.
It is possible that the first new nuclear power plant to be built in the United States since the 1970s may be installed in the remote town of Galena, Alaska. The town's City Council approved the idea, and Toshiba proposed to install its model 4S "nuclear battery" in Galena free of charge as a test.
See also nuclear power phase-out, nuclear energy policy.
[edit]
Types of reactors
NC State's PULSTAR Reactor is a 1 MW pool-type research reactor with 4% enriched, pin-type fuel consisting of UO2 pellets in zircaloy cladding.
Enlarge
NC State's PULSTAR Reactor is a 1 MW pool-type research reactor with 4% enriched, pin-type fuel consisting of UO2 pellets in zircaloy cladding.
The control room of NC State's Pulstar Nuclear Reactor.
Enlarge
The control room of NC State's Pulstar Nuclear Reactor.
A number of reactor technologies have been developed. Fission reactors can be divided roughly into two classes, depending on the energy of the neutrons that are used to sustain the fission chain reaction.
* Thermal (slow) reactors use slow or thermal neutrons. These are characterized by having moderating materials which are intended to slow the neutrons until they approach the average kinetic energy of the surrounding particles, that is, until they are thermalized. Thermal neutrons have a far higher probability of fissioning U-235, and a lower probability of capture by U-238 than the faster neutrons that result from fission do. As well as the moderator, thermal reactors have fuel (fissionable material), containments, pressure vessels, shielding, and instrumentation to monitor and control the reactor's systems. Most power reactors are of this type, and the first plutonium production reactors were thermal reactors using graphite as the moderator. Some thermal power reactors are more thermalised than others; Graphite (ex. Russian RBMK reactors) and heavy water moderated plants (e.g. Canadian CANDU reactors) tend to be more thoroughly thermalised than PWRs and BWRs, which use light water (normal water) as the moderator (due to the extra thermalization, these types can use natural uranium/unenriched fuel).
* Fast reactors use fast neutrons to sustain the fission chain reaction, and are characterized by the lack of moderating material. They require highly enriched fuel (sometimes weapons-grade), or plutonium in order to reduce the amount of U-238 that would otherwise capture fast neutrons. Some are capable of producing more fuel than they consume, usually by converting U-238 to Pu-239. Some early power stations were fast reactors, as are some Russian naval propulsion units, and construction of prototypes is continuing, see fast breeder, but overall the class has not achieved the success of thermal reactors in any application. An example of this type of reactor is the Fast Breeder Reactor (FBR).
Thermal power reactors can again be divided into three types, depending on whether they use pressurised fuel channels, a large pressure vessel, or gas cooling.
* Pressure vessels holding steam heated by the reactor are used by most commercial and naval reactors. This serves as a layer of shielding and containment.
* Pressurised channels are used by the RBMK and CANDU reactors. Channel-type reactors can be refuelled under load, which has advantages discussed under CANDU reactor.
* Gas-cooled reactors are cooled by a circulating inert gas, usually helium, but nitrogen and carbon dioxide have also been used. Utilisation of the heat varies, depending on the reactor. Some reactors run hot enough that the gas can directly power a gas turbine. Older designs usually run the gas through a heat exchanger to make steam for a steam turbine. The pebble bed reactor uses a gas-cooled design.
Since water serves as a moderator, it cannot be used as a coolant in a fast reactor. Most designs for fast power reactors have been cooled by liquid metal, usually molten sodium. They have also been of two types, called pool and loop reactors.
[edit]
Current families of reactors
* Pool type reactor
* Pressurized water reactor (PWR)
* Boiling water reactor (BWR)
* Fast breeder reactor (FBR)
* Pressurized Heavy Water Reactor (PHWR) or CANDU
* United States Naval reactor
[edit]
Obsolete types still in service
* Magnox reactor
* Advanced gas-cooled Reactor (AGR)
* Light water cooled graphite moderated reactor (RBMK)
[edit]
Other types of reactors
* Aqueous Homogeneous Reactor
* Liquid Fluoride Reactor
[edit]
Advanced reactors
More than a dozen advanced reactor designs are in various stages of development.[10]Some are evolutionary from the PWR, BWR and PHWR designs above, some are more radical departures. The former include the Advanced Boiling Water Reactor (ABWR), two of which are now operating with others are under construction, and the planned passively safe ESBWR and AP1000 units (see Nuclear Power 2010 Program). The best-known radical new design is the Pebble Bed Modular Reactor (PBMR), a High Temperature Gas Cooled Reactor (HTGCR). The Clean And Environmentally Safe Advanced Reactor (CAESAR) is a nuclear reactor concept that uses steam as a moderator - this design is still in development. Possible designs of subcritical reactors exist on the drawing board, notably the energy amplifier, awaiting political support and funding. Some, such as the Integral Fast Reactor (IFR), have been cancelled due to a political climate unfavorable to nuclear power.
[edit]
Generation IV reactors
Even more-advanced reactors are also on the drawing boards. These are the Generation IV reactors[11], which are divided into six overall design classes.
* Gas cooled fast reactor
* Lead cooled fast reactor
* Molten salt reactor
* Sodium-cooled fast reactor
* Supercritical water reactor
* Very high temperature reactor
[edit]
Nuclear fuel cycle
Main article: nuclear fuel cycle
Thermal reactors generally depend on refined and enriched uranium. Some nuclear reactors can operate with a mixture of plutonium and uranium (see MOX). The process by which uranium ore is mined, processed, enriched, used, possibly reprocessed and disposed of is known as the nuclear fuel cycle.
Uranium is sampled and mined as other metals are, via open-pit mining or leach mining. Raw uranium ore found in the United States ranges from 0.05% to 0.3% uranium oxide. Uranium ore is not rare; the largest probable resources, extractable at a cost of US$80 per kilogram or cheaper, are located in Australia, Kazakhstan, Canada, South Africa, Brazil, Namibia, Russia, and the United States.
The raw ore is then milled, where it is ground and chemically leached. The resulting powder of natural uranium oxide is called "yellowcake". The yellowcake powder is then converted to uranium hexafluoride to prepare for enrichment.
Under 1% of the uranium found in nature is the easily fissionable U-235 isotope and as a result most reactor designs require enriched fuel. Enrichment involves increasing the percentage of U-235 and is usually done by means of gaseous diffusion or gas centrifuge. The enriched result is then converted into uranium dioxide powder, which is pressed and fired onto pellet form. These pellets are stacked into tubes which are then sealed and called fuel rods. Many of these fuel rods are used in each nuclear reactor.
Most BWR and PWR commercial reactors use uranium enriched to about 4% U-235, many research reactors use highly enriched, or weapons grade uranium, while some commercial reactors with a high neutron economy do not require the fuel to be enriched at all.
[edit]
Fueling of nuclear reactors
The amount of energy in the reservoir of nuclear fuel is frequently expressed in terms of "full-power days," which is the number of 24-hour periods (days) a reactor is scheduled for operation at full power output for the generation of heat energy. The number of full-power days in a reactor's operating cycle (between refueling outage times) is related to the amount of fissile uranium-235 (U-235) contained in the fuel assemblies at the beginning of the cycle. A higher percentage of U-235 in the core at the beginning of a cycle will permit the reactor to be run for a greater number of full-power days.
At the end of the operating cycle, the fuel in some of the assemblies is "spent," and is discharged and replaced with new (fresh) fuel assemblies. Although in practice, it is the buildup of reaction poisons in nuclear fuel that determines the lifetime of nuclear fuel in a reactor; long before all possible fissions have taken place, the buildup of long-lived neutron absorbing fission products damps out the chain reaction. The fraction of the reactor's fuel core replaced during refueling is typically one-fourth for a boiling-water reactor and one-third for a pressurized-water reactor.
Not all reactors need to be shut down for refueling; for example, pebble bed reactors, RBMK reactors,molten salt reactors, Magnox and CANDU reactors allow fuel to be shifted through the reactor while it is running. In a CANDU reactor, this also allows individual fuel elements to be moved about within the reactor core to places that are best suited to the amount of U-235 in the fuel element.
The amount of energy extracted from nuclear fuel is called its "burn up," which is expressed in terms of the heat energy produced per initial unit of fuel weight. Burn up is commonly expressed as megawatt days thermal per metric ton of initial heavy metal.
[edit]
Waste management
The final stage of the nuclear fuel cycle is the management of the still highly radioactive, "spent" fuel, which constitutes the most problematic component of the nuclear waste stream. After fifty years of nuclear power the question of how to deal with this material remains fraught with safety concerns and technical problems, and one of the most important lines of criticism of the industry is based on the long-term risks and costs associated with dealing with the waste.
Management of the spent fuel can include various combinations of storage, reprocessing, and disposal. In practice storage has been the primary modality so far. Typically the spent fuel rods are stored in a pool of water which is usually located on-site. The water provides both cooling for the still-decaying uranium, and shielding from the continuing radioactivity. After a few decades some on-site storage involves moving the now cooler, less radioactive fuel to a dry-storage facility, where the fuel is stored in steel and concrete containers which are monitored carefully.
Another, more permanent method of disposal of high-level nuclear waste calls for the material to be buried deep underground in certain geological formations. The Canadian government, for example, is seriously considering this method of disposal, known as the Deep Geological Disposal concept. Under the current plan, a vault is to be dug 500 to 1000 meters below ground, under the Canadian Shield, one of the most stable landforms on the planet. The vaults are to be dug inside geological formations known as batholiths, formed about a billion years ago. The used fuel bundles will be encased in a corrosion-resistant container, and further surrounded by a layer of buffer material, possibly of a special kind of clay (bentonite clay). The case itself is designed to last for thousands of years, while the clay would further slow the corrosion rates of the container. The batholiths themselves are chosen for their low ground-water movement rates, geological stability, and low economic value[12].
The Finnish government has already started building a vault to store nuclear waste 500 to 1000 meters below ground, not far from the nuclear plant at Olkiluoto.
Storing high level nuclear waste above ground for a century or so is considered appropriate by many scientists. This allows for the material to be more easily observed and any problems detected and managed, while the decay over this time period significantly reduces the level of radioactivity and the associated harmful effects to the container material. It is also considered likely that over the next century newer materials will be developed which will not break down as quickly when exposed to a high neutron flux thus increasing the longevity of the container once it is permanently buried.
Reprocessing is attractive in principle because (1) it can recycle nuclear fuel and (2) it can prepare the waste material for disposal. Considerable experience with reprocessing in France however, has indicated that a one way fuel cycle based on extracting and processing fresh supplies of uranium and storing the spent fuel is more economical than reprocessing, not the least because in the process of plutonium extraction, the volume of high-level liquid radioactive waste increases about 17-fold.
[edit]
Natural nuclear reactors
A natural nuclear fission reactor can occur under certain circumstances that mimic the conditions in a constructed reactor. The only known natural nuclear reactor formed 2 billion years ago in Oklo, Gabon, Africa. [13] Such reactors can no longer form on Earth: radioactive decay over this immense time span has reduced the proportion of U-235 in naturally occurring uranium to below the amount required to sustain a chain reaction.
The natural nuclear reactors formed when a uranium-rich mineral deposit became inundated with groundwater that acted as a neutron moderator, and a strong chain reaction took place. The water moderator would boil away as the reaction increased, slowing it back down again and preventing a meltdown. The fission reaction was sustained for hundreds of thousands of years.
These natural reactors are extensively studied by scientists interested in geologic radioactive waste disposal. They offer a case study of how radioactive isotopes migrate through the earth's crust. This is a significant area of controversy as opponents of geologic waste disposal fear that isotopes from stored waste could end up in water supplies or be carried into the environment.
[edit]
See also
* Nuclear Reactor Operator Badge
* United States Naval reactor
* List of nuclear reactors
* Green Field status
* Nuclear reactor physics
* Nuclear power
* Nuclear fission
* Nuclear fusion
* Nuclear power plant
* Nuclear meltdown
* Power plant
* Nuclear waste
* Electricity generation
* Nuclear physics
* Enrico Fermi
* Manhattan Project
* Nuclear marine propulsion
* Technology assessment
* List of nuclear reactors
* List of nuclear accidents
* Energy amplifier
* Future energy development
* SCRAM
* SSTAR - LLNL design for a "world" reactor
[edit]
References
1. ^ Oklo: Natural Nuclear Reactors. Office of Civilian Radioactive Waste Management. Retrieved on June 28, 2006.
2. ^ From Obninsk Beyond: Nuclear Power Conference Looks to Future. International Atomic Energy Agency. Retrieved on June 27, 2006.
3. ^ Nuclear Power in Russia. World Nuclear Association. Retrieved on June 27, 2006.
4. ^ 1956:Queen switches on nuclear power. BBC news. Retrieved on June 28, 2006.
5. ^ The Rise and Fall of Nuclear Power. Public Broadcasting Service. Retrieved on June 28, 2006.
6. ^ Backgrounder on Chernobyl Nuclear Power Plant Accident. Nuclear Regulatory Commission. Retrieved on June 28, 2006.
7. ^ Nuclear energy: the majority of Italians remain sceptical but one out of three says yes. Observa. Retrieved on June 28, 2006.
8. ^ EFFECT OF HURRICANE ANDREW ON TURKEY POINT NUCLEAR GENERATING STATION AND LESSONS LEARNED. Nuclear Regulatory Commission. Retrieved on June 28, 2006.
9. ^ SUPPLEMENT 1:EFFECT OF HURRICANE ANDREW ON TURKEY POINT NUCLEAR GENERATING STATION AND LESSONS LEARNED. Nuclear Regulatory Commission. Retrieved on June 28, 2006.
10. ^ Advanced Nuclear Power Reactors. Uranium Information Centre. Retrieved on June 28, 2006.
11. ^ Generation IV Nuclear Reactors. Uranium Information Centre. Retrieved on June 28, 2006.
12. ^ How is high-level nuclear waste managed in Canada?. The Canadian Nuclear FAQ. Retrieved on June 28, 2006.
13. ^ Oklo's Natural Fission Reactors. American Nuclear Society. Retrieved on June 28, 2006.
[edit]
External links
* The Nuclear Reactor crisis
* Worldwide maps of nuclear power stations
* Uranium.Info publishing uranium price since 1968.
* Energy Information Administration provides lots of statistics and information on the industry.
* World Nuclear Fuel Facilities
* The US Nuclear Regulatory Commission supervises the US Nuclear industry
* The Idaho National Engineering and Environmental Laboratory developed nuclear reactor technology in the United States - INEL Newsdesk - Experimental Breeder Reactor-I opens for summer tours
* The International Atomic Energy Agency (IAEA) works with its Member States and multiple partners worldwide to promote safe, secure and peaceful nuclear technologies.
o IAEA Website
o IAEA's Power Reactor Information System (PRIS)
o IAEA's Knowledge Base on Gas Cooled Reactors
o IAEA's Web directory of nuclear related resources on the Internet
* The Pebble Bed Modular Reactor - Whyfiles.org - On a bed of pebbles
* World Nuclear Association - A pro nuclear site
* Greenpeace Nuclear Campaign - An anti-nuclear site
* A Debate: Is Nuclear Power The Solution to Global Warming?
* Environmentalists for Nuclear Power, pro nuclear site
* SCK.CEN Belgian Nuclear Research Centre - pro nuclear site
* The Nuclear Energy Option by Bernard Cohen. Pro nuclear book which compares risks of nuclear power with other methods of energy generation.
* Union of Concerned Scientists, Concerns re: US nuclear reactor program
* The Canadian Nuclear FAQ - a very information-rich resource about Canadian CANDU reactors.
* Critical Hour: Three Mile Island, The Nuclear Legacy, And National Security Online book by Albert J. Fritsch, Arthur H. Purcell, and Mary Byrd Davis
* The Nuclear Boy Scout - Eagle and Eagle TV production about David Hahn's nuclear reactor experiment
* The Radioactive Boy Scout What happened when teenager David Hahn tried a dangerous experiment in his back yard
Nuclear Technology
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Nuclear material Nuclear fuel | Fertile material | Thorium | Uranium | Enriched uranium | Depleted uranium | Plutonium
Nuclear power Nuclear power plant | Radioactive waste | Fusion power | Future energy development | Pressurized water reactor | Boiling water reactor | Generation IV reactor | Fast breeder reactor | Fast neutron reactor | Magnox reactor | Advanced gas-cooled reactor | Gas cooled fast reactor | Molten salt reactor | Liquid metal cooled reactor | Lead cooled fast reactor | Supercritical water reactor | Very high temperature reactor | Pebble bed reactor | Integral Fast Reactor | Nuclear propulsion | Nuclear thermal rocket | Radioisotope thermoelectric generator
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Nuclear weapons History of nuclear weapons | Nuclear warfare | Nuclear arms race | Nuclear weapon design | Effects of nuclear explosions | Nuclear testing | Nuclear delivery | Nuclear proliferation | List of countries with nuclear weapons | List of nuclear tests
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Page 1
W
How Renewable Energy and Energy Efficiency Can Fuel Our Future
Clean Power Comes on Strong
Explore, enjoy and protect the planet
e have the potential
to produce almost all of our electricity from clean
e n e rgy sources. Today, we have the technology
and the know-how to move beyond our depend-
ence on polluting power plants by using clean,
safe, and affordable renewable energy.
By harnessing renewable sources of energ y
like the sun and the wind, we can transform how
we produce electricity. Today’s solar panels effi-
ciently transform sunlight into electricity while
blending into the design of homes and off i c e
buildings. Modern wind turbines rise high above
the ground, capturing the strongest winds to pro-
duce reliable electricity.
A clean energy future will rely not just on re-
newable energy, but also on better use of the en-
e rgy we currently produce. By making the energ y
we produce last longer, or by increasing “energ y
e fficiency,” we can avoid the need for new pol-
luting power plants. We can increase energy eff i-
ciency by using available technologies that do the
same amount of work but use less energy, like a
computer that goes to sleep when it’s not in use.
Clean, renewable energy like solar and wind
power currently produces about 2 percent of our
electricity nationwide. In contrast, nearly 90 per-
cent of our electricity still comes from polluting
s o u rces of energy like coal and nuclear power.
C o a l - b u rning power plants are the nation’s
l a rgest source of carbon dioxide, the heat-trap-
ping pollutant that causes global warming. Coal-
f i red power plants are also responsible for
pollution that increases asthma attacks and wors-
ens environmental problems like acid rain, haze,
smog, and other air and water pollution.
We can face these challenges by taking steps
today towards a brighter energy future.
Using existing technology and re s o u rces, we
can cut our reliance on existing polluting power
plants by providing at least 20 percent of our
electricity from renewable sources of energy by
2020 and by increasing the energy efficiency of
our appliances and homes.
Wind energy is a
powe rful source of clean energy, p roducing elect ri c i ty with no global
wa rming po l l u t i o n .
The Answer is Blowin’ in the Wind
Page 2
Wind energy
is the fastest-growing
source of power on
the planet.
With our tremendous wind re s o u rc e s ,
the United States can become a world
leader in wind energy. Already, wind
turbines in this country produce enough
electricity to meet the needs of more
than 1 million households.
A single modern wind turbine can
produce enough power to meet the an-
nual electricity needs of 500 average
homes. In recent years the price of wind
has fallen dramatically, making it in-
c reasingly competitive with fossil fuels.
The federal government’s National Re-
newable Energy Laboratory projects that
the price of wind energy will fall even
further over the next decade, making it
the most economically competitive re-
newable energy technology.
As a growing power source, wind
e n e rgy can become a major force for
economic development. Wind develop-
ment can save consumers money and
bring construction jobs, leasing ro y a l-
ties, and increased tax revenues to
local communities. Supplying even 5
p e rcent of the country’s electricity with
wind power by 2020 would add $60
billion in capital investment in rural
America, provide $1.2 billion in new
income for farmers and rural landown-
ers, and create 80,000 new jobs. Farm-
ers and ranchers can also use wind
power as a new “crop,” earning $2,000
per year in lease payments per turbine,
helping insulate them from falling com-
modity prices. A single turbine takes
up less than a quarter of an acre, in-
cluding access roads, and farmers can
g row crops or graze livestock right up
to the base of the turbines.
How Does it Work?
Standing as tall as 300 feet to capture
the full force of the wind, modern wind
“You’ve been gettin’your
hat blown off your head
your whole life.
It’s time to stop cussin’and start makin’some money.”
Winds have shaped the rugged
West Texas landscape for ages.Now those winds are fueling a clean energy revolution
that is revitalizing the West Texas economy.Since 1999,wind energy has infused the
state with more than $1 billion in capital investment,providing farmers,ranchers and
local communities with new sources of income.As a result of state policies that require
utilities to purchase renewable energy,the old oil town of McCamey is now home to
multiple wind farms (above) that produce enough electricity to power 125,000 homes.
By replacing electricity generated by fossil fuels,these wind farms take 880,000 tons of
carbon dioxide out of the air every year.
SUCCESS STORY:
Wind Power in Action
turbines use state-of-the-art technology
to turn wind into electricity. When the
wind blows, the blades begin to spin,
t u rning an electric generator to cre a t e
electricity. This electricity is carried
through the turbine tower underground,
where it feeds into the electric grid.
— Ra n dy Sowe l l ,CieloWind LLC
Page 3
When Oberlin College decided to
build a new Environmental Science building,they constructed a hallmark of environ-
mental engineering.Solar power became an integral component of the building’s
design,dispelling myths that the Ohio climate could not support solar energy.A rooftop
array of solar photovoltaic panels provides more than half of the building’s energy
needs,saving money and protecting the environment.The solar array is connected to
the electrical grid,allowing Oberlin to sell excess electricity back to its utility on sunny
days,while using backup energy from the grid on cloudier days.The Science building
also employs energy efficient designs that use only 14 percent as much energy as a typ-
ical office building.By using solar power,Oberlin reduces its energy bills and keeps more
than 350 tons of carbon dioxide out of the air each year.As Professor David Orr says,
“Even in cloudy Ohio,by God,this stuff works.”
SUCCESS STORY:
Solar Power in Action
The sun
is the
ultimate source of
energy.
All the energy stored in the earth’s re-
serves of coal, oil, and natural gas is
equal to the energy from only 20 days of
sunshine. With today’s technologies, we
can harness this energy to produce elec-
tricity. While some parts of the country
a re sunnier than others, most areas re-
ceive enough sunshine to make solar en-
e rgy a powerful source of clean and
affordable electricity.
Thanks in part to successful research
and development, the cost of solar tech-
nologies has plummeted in re c e n t
decades, approaching the cost of fossil
fuels, and is likely to fall even further.
How Does it Work?
Solar technologies allow us to cap-
t u re the sun’s energy in two principal
ways. Solar photovoltaic panels, which
f requently sit atop buildings, convert
sunlight directly into electricity. These
solar panels are made of cutting-edge
silicon materials, similar to those used in
computer chips. As light passes thro u g h
the panels, it creates a current, generat-
ing electricity. This process of convert-
ing light (photons) to electricity
(voltage) gives us the photovoltaic ef-
fect. Also currently in use are solar ther-
mal systems, which use the sun’s heat to
w a rm water for our businesses and
homes.
”Even in cloudy
Ohio, by God,
this stuff works.”
— Pro fessor David Orr, Obe rlin Co l l e g e
Page 4
Why aren’t we using more renewable energy today?
Ma ny economic and po l i t i cal barriers keep re n ewable energy from realizing its
full po te nt i a l .Huge tax subsidies—along with heavy re s e a rch and deve l o p m e nt
f u n d i n g — for polluting power sources like co a l ,o i l ,and nuclear,h ave far out-
weighed inve s t m e nts in clean,re n ewable energy,giving a huge adva ntage to
polluting te c h n o l og i e s.Ma rket barriers also exist that make it difficult and co s t l y
for re n ewable energy sources to co n n e ct to the elect ri c i ty grid and transmit their
power to custo m e r s.
But these barriers ca n
be ove rco m e.In state s
w h e re suppo rt i ve po l i-
cies have been enact-
e d,re n ewable energy
has flouri s h e d.
Are there down-
sides to wind
power?
Some birds are killed
by flying into wind tur-
bines.Unfortunately,
this is a problem with
many tall structures
like buildings and cell phone towers. For instance,cell-phone towers are
responsible for double the bird mortality attributed to wind turbines.The most
important step wind energy developers can take to address this concern is to
properly site wind turbines in areas where they will not pose a threat to birds.
Responsible siting of wind turbines can also mitigate the visual impacts of
wind development.
The far greater threat to birds and other wildlife comes from neglecting our
responsibility to combat global warming. Global warming could shift whole
species of birds north, causing a loss of songbirds here in the United States and
potentially making it more difficult for these species to survive.Appropriately
sited wind turbines and other renewable energy sources will play a pivotal role
in curbing global warming and protecting natural habitats.
Is renewable energy reliable?
The advanced technology of wind turbines and solar panels allows them to
produce substantial amounts of electricity even on days with soft winds or lit-
tle sunshine. As a source of home-grown energy, renewable energy helps
diversify and decentralize our electricity mix,making it more secure.
Are hydropower and nuclear power renewable?
The Sierra Club supports renewable energy sources that can be harnessed
with minimal harm to the environment.Large hydropower facilities can be
extremely damaging to surrounding habitats and destructive to species that
live in them.The Sierra Club does support increasing the efficiency of existing
hydropower facilities.Nuclear power produces huge amounts of highly
radioactive waste that is dangerous for tens of thousands of years.
Geothermal
energy
is right
under our feet.
The Earth’s core is like an inner sun,
heating the Earth’s surface and warming
the water and rocks beneath. This
steaming water and rock can be used to
generate heat and electricity. The upper-
most six miles of the Earth’s crust alone
contains more energy than all the oil and
gas reserves in the world.
G e o t h e rmal re s o u rces are abundant,
affordable, and available 24 hours a day,
365 days a year. Currently, geotherm a l
e n e rgy provides enough electricity to
power nearly 4 million American homes.
Using existing technology, geotherm a l
power plants run more efficiently and
reliably than do coal and nuclear facili-
ties. The U.S. Department of Energy esti-
mates that geothermal power plants
prevent some 22 million tons of carbon
dioxide from escaping into the atmos-
p h e re every year, helping curb global
warming by reducing pollution from our
nation’s biggest culprits, coal-fire d
power plants.
Biomassenergy
provides plant-
powered heat
and electricity.
Plants absorb and store energy fro m
the sun as they grow. With the right
technologies and careful attention to re-
sponsible land-management practices,
the energy contained in plants can be
h a rnessed to produce heat and electric-
ity. Sustainable, dedicated energy cro p s
have the potential to supply a significant
portion of America’s energy needs while
p roviding farmers with a valuable new
market for their crops.
Frequently Asked Questions
The cost of renewable
energy has fallen
sharply since 1980 and
will continue to drop.
Page 5
According to the U.S. Department of Energy,producing 20 percent of our
nation’s electricity with renewable energy by 2020 is not only possible,but it is
affordable.When combined with strong energy efficiency programs, we can spur
innovation,clean up our environment, cut our energy bills,and fuel economic
growth.
Spur Innovation
The United States, once a leader in renewable energy development,has fallen
behind other nations in pursuing clean energy solutions. By reinvigorating our
commitment to renewable energy and energy efficiency,we can develop the
technologies of tomorrow and find solutions for today’s most pressing prob-
lems.
Curb Global Warming
Our nation’s fossil fuel power plants are the primary source of carbon dioxide,
the principal global warming pollutant. Boosting our use of renewable energy
and increasing energy efficiency can eliminate the need for nearly a thousand
new power plants over the next 20 years.
Improve Public Health
Pollution from existing power plants contributes to over 600,000 asthma
attacks each year. Increasing energy efficiency and our use of renewable ener-
gy can take dangerous pollutants out of the air and let us all breathe a little
easier.
Cut Energy Bills
Clean energy choices translate into good financial choices.Together, strong
renewable energy and energy efficiency policies could save a typical family
$350 per year in lower energy bills by 2020.In addition,more renewable ener-
gy means more insulation from price spikes.Similar to good investors diversi-
fying their stock portfolio,using more renewable energy will diversify our
electricity mix and make us less dependent on the performance of a small
number of fuels.
Enhance Energy Security
Renewable energy is a reliable source of “home-grown”energy,allowing com-
munities and homes to generate their own power.While current power plants
and transmission lines could be inviting targets for terrorists, decentralized
renewable energy sources make it more difficult to disrupt large portions of
the electrical grid.
Bring Jobs,Income,and Revenue to Rural America
Renewable energy development can be a powerful economic support for
rural areas.Farmers and ranchers have received $2,000 per year in lease pay-
ments for each wind turbine operating on their land.Renewable energy proj-
ects also infuse local communities with increased tax revenues and generate
local jobs.
Harvesting the Benefits of Clean Energy
Energy
efficiency
is easy and saves you
money.
The cleanest way to meet our elec-
tricity needs is by using less of it in the
first place. By planning intelligently and
using existing technology, we can cut
our electricity consumption and slow
down the meter. Improving energy eff i-
ciency lowers energy bills, eliminates
the need for new power plants, in-
c reases our energy security, and keeps
our environment clean.
We have already seen that energy ef-
ficiency works. Today’s efficiency stan-
dards save as much energy as is used
by 6.5 million households. This pre-
vents as much global warming pollution
as if we took 25 million cars off the
road. And we can do much more with
only small improvements. For example,
if every household in the United States
switched to Energy Star light fixture s
(see “Take Action” on the back page of
this fact sheet), we could prevent 50
million tons of global warming pollu-
tion per year, which would be equiva-
lent to taking another 10 million cars off
the road. Everyone can take personal
responsibility to make sure our homes,
businesses, and appliances are as eff i-
cient as possible.
Page 6
gy sources.If so, sign up. If not,tell your utility you’d like
clean energy options.Check with your local home
improvement store to find out if it carries photovoltaic
panels for installation on rooftops.
Buy energy-efficient electronics and appliances.
Replacing an old refrigerator, air conditioner,or heating
system with an energy-efficient model will save you
money on your electricity bill and cut global warming
pollution.Look for the Energy Star label on new appli-
ances or go to www.energystar.gov to find the most ener-
gy-efficient products.
Bring renewable energy to your community. Talk to
people at your workplace, local school system,or place of
worship about purchasing a portion of its electricity from
clean,renewable energy sources.Finance the project by
finding money-saving energy efficiency projects.
For more ideas,please visit our Web site at
www.sierraclub.org/energy.
Explore,enjoy and protect the planet
408 C St.NE • Washington, D.C.20002 • (202) 547-1141 • www.sierraclub.org
Please tell your public officials that you care about making
renewable energy and energy efficiency a part of our energy
future.Urge your public officials to:
Produce 20 percent of our electricity from renewable
energy sources by 2020.
Establish strong energy efficiency standards for elec-
tronics, home appliances, and buildings.
You can also make important energy choices in your home
and workplace.
Bu t ton up your house to save energy by we at h e r - s t ri p-
ping your windows and doo rways.St a rt replacing old light-
bulbs with energy - e f f i c i e nt co m p a ct fluore s ce nt bulbs.
Fi n a l l y,call your local utility to get a free energy audit and
l e a rn about more ways to save money and energy.
Make your home renewable. Call your local utility and
ask whether it offers electricity produced from clean ener-
Take Action:Increase Renewable Energy Use and Improve Energy Efficiency
|
