The Promise of Fusion Power
Nuclear fusion as a power source has long been seen as technology that is very promising but just out of reach. With significantly less radioactive and toxic waste than fission reactors, and with seawater as the primary source of fuel, fusion promises to finally deliver on the dreams first ascribed to fission in the early days of the nuclear age.
One problem is that fusion reactors require a lot of power as an input in order to produce even more power as an output. Another problem is that the technology to contain a sustained thermonuclear reaction for an extended period of time has proven to be more elusive than was envisioned a generation ago.
It will take until 2050, by current estimates, to reach the point where a fusion reactor will be out of the experimental stage and in use as a practical source of electricity. Meanwhile, nuclear fission reactors are the best source of electricity with current human technology. Solar, wind, hydroelectric, and other sources must be pursued as alternatives to coal as sources of electricity, but those sources are bound by practical limitations.
So, what can we do now to prepare for the day when fusion power can replace fission as the primary source of electricity in the U.S. and other industrialized countries? The answer is breeder reactors. By replacing the aging traditional fission reactors currently in use with new breeder reactors, we can prepare for the future while greatly reducing the radioactive waste requiring long term storage on the order of 10,000 years.
First, you need a breeder reactor that creates plutonium as a byproduct while generating power. Plutonium is a byproduct of uranium fission reactors, and only a portion of the plutonium generated is consumed in fission events within the reactor. Unlike traditional fission power reactors, breeder reactors can also avoid the need to store radioactive byproducts with extremely long half lives, because almost all of the byproducts are fissionable materials. Other byproducts include small amounts of deuterium and tritium, isotopes of hydrogen that can be used as fuel in a fusion reactor.
Next, the second fission reactor consumes the plutonium and other fissionable materials, while generating more power and producing less overall radioactive waste for long term storage. Just as in the breeder reactor, byproducts include deuterium and tritium, which can be used as additional fuel in a fusion reactor.
Eventually, the a third, fusion reactor can be built on the site of the first two reactors. The fusion reactor generates power using the deuterium and tritium generated in the fission reactors as well as tritium that can be produced from the lithium used as a heat transfer material in the fusion reactor. Most of the deuterium would be extracted from seawater using the same process that created the heavy water used in the fission reactors as coolant.
Fusion reactors require a large amount of power. Nuclear fusion is the process that powers the sun and other stars. It requires ionized atoms in a superheated plasma contained by magnetic fields in a torroidal chamber. The plasma must be contained for a long time, which requires extremely powerful electromagnets that require a lot of power. The resulting reaction produces significantly more power than it consumes, but it requires an external power source to start and restart the reaction. The fission reactors can supply that power while also providing power for consumers.
By using three (or more) reactors in tandem, significantly more power can be extracted from the same amount of uranium as a single uranium reactor, while also reducing radioactive waste. The fusion reactor also can be fueled primarily by deuterium extracted from seawater, but it can run more efficiently using tritium generated as byproducts of the fission reactors and from the fusion reactor itself.
The fission reactors can generate power for decades while also generating tritium to be stored until the fusion reactor can come online. By that time, the amount of tritium on hand will be enough to combine with the more plentiful deuterium to fuel the fusion reactor for quite some time, while the breeder reactor technology also improves to more efficiently produce more tritium.
Also, by continuing to increase our capability with nuclear fission in parallel to investing in fusion technology, we can develop ways to more efficiently process the fissionable byproducts of the breeder reactor and the plutonium reactor. That may even allow us to process the current accumulation of radioactive nuclear isotopes to generate more power while reducing the accumulated waste produced by current reactors.
Next, the second fission reactor consumes the plutonium and other fissionable materials, while generating more power and producing less overall radioactive waste for long term storage. Just as in the breeder reactor, byproducts include deuterium and tritium, which can be used as additional fuel in a fusion reactor.
Eventually, the a third, fusion reactor can be built on the site of the first two reactors. The fusion reactor generates power using the deuterium and tritium generated in the fission reactors as well as tritium that can be produced from the lithium used as a heat transfer material in the fusion reactor. Most of the deuterium would be extracted from seawater using the same process that created the heavy water used in the fission reactors as coolant.
Fusion reactors require a large amount of power. Nuclear fusion is the process that powers the sun and other stars. It requires ionized atoms in a superheated plasma contained by magnetic fields in a torroidal chamber. The plasma must be contained for a long time, which requires extremely powerful electromagnets that require a lot of power. The resulting reaction produces significantly more power than it consumes, but it requires an external power source to start and restart the reaction. The fission reactors can supply that power while also providing power for consumers.
By using three (or more) reactors in tandem, significantly more power can be extracted from the same amount of uranium as a single uranium reactor, while also reducing radioactive waste. The fusion reactor also can be fueled primarily by deuterium extracted from seawater, but it can run more efficiently using tritium generated as byproducts of the fission reactors and from the fusion reactor itself.
The fission reactors can generate power for decades while also generating tritium to be stored until the fusion reactor can come online. By that time, the amount of tritium on hand will be enough to combine with the more plentiful deuterium to fuel the fusion reactor for quite some time, while the breeder reactor technology also improves to more efficiently produce more tritium.
Also, by continuing to increase our capability with nuclear fission in parallel to investing in fusion technology, we can develop ways to more efficiently process the fissionable byproducts of the breeder reactor and the plutonium reactor. That may even allow us to process the current accumulation of radioactive nuclear isotopes to generate more power while reducing the accumulated waste produced by current reactors.
At the same time, the use solar and wind power can be used to provide supplemental renewable power as part of a long term strategy for reducing dependence on fossil fuels. Oil and gas reserves won't last forever, and they should be limited to use where electric power is not practical.
For example, in addition to more farms of large wind turbines, why not generate power from wind in cities with rooftop helix-style turbines that can extract energy from swirling winds. In cities with lots of sun, solar panels can generate electricity on otherwise barren rooftops, as well
We need an "all of the above" energy strategy that leverages ongoing improvements in technology, and we can't limit ourselves to renewable sources. Fusion power will be necessary for many years to come. It is worth the investment and the wait.
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