In a world increasingly aware of and affected by global warming, the news that was a record year for greenhouse gases levels was something of a blow. With the world's population due to hit nine billion by , it highlights the increasingly urgent need to find a clean, reliable and renewable source of energy.
India hopes it has the answer: thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust. The pro-thorium lobby claim a single tonne of thorium burned in a molten salt reactor MSR — typically a liquid fluoride thorium reactor LFTR — which has liquid rather than solid fuel, can produce one gigawatt of energy. A traditional pressurised water reactor PWR would need to burn tonnes of uranium to produce the same amount of energy. They also produce less waste, have no weapons-grade by-products, can consume legacy plutonium stockpiles and are meltdown-proof — if the hype is to be believed.
India certainly has faith, with a burgeoning population, chronic electricity shortage, few friends on the global nuclear stage it hasn't signed the nuclear non-proliferation treaty and the world's largest reserves of thorium. There is a significant sticking point to the promotion of thorium as the 'great green hope' of clean energy production: it remains unproven on a commercial scale.
While it has been around since the s and an experimental 10MW LFTR did run for five years during the s at Oak Ridge National Laboratory in the US, though using uranium and plutonium as fuel it is still a next generation nuclear technology — theoretical.
Like all nuclear power production they rely on extensive taxpayer subsidies; the only difference is that with thorium and other breeder reactors these are of an order of magnitude greater, which is why no government has ever continued their funding.
China's development will persist until it experiences the ongoing major technical hurdles the rest of the nuclear club have discovered, he says. Others see thorium as a smokescreen to perpetuate the status quo: the world's only operating thorium reactor — India's Kakrapar-1 — is actually a converted PWR, for example. In his reading, thorium is merely a way of deflecting attention and criticism from the dangers of the uranium fuel cycle and excusing the pumping of more money into the industry.
Conventional, civilian bands are a no-go because they'd give away the team's position. As the fighter jet and its automated wingmen cross into hostile territory, they are already sweeping the ground below with radio-frequency, infrared, and optical sensors to identify potential threats. On a helmet-mounted visor display, the pilot views icons on a map showing the movements of antiaircraft batteries and RF jammers, as well as the special forces and the locations of allied and enemy troops.
While all this is going on, the fighter jet's autonomous wingmen establish an ad hoc, high-bandwidth mesh communication network that cuts through the jamming by using unjammed frequencies, aggregating signals across different radio channels, and rapidly switching among different channels.
Through a self-organizing network of communication nodes, the piloted fighter in the air connects to the special forces on the ground. As soon as the network is established, the soldiers begin transmitting real-time video of artillery rockets being transported into buildings.
The fighter jet acts as a base station, connecting the flying mesh network of the UAVs with a network of military and commercial satellites accessible to commanders all over the world.
Processors distributed among the piloted and unpiloted aircraft churn through the data, and artificial-intelligence AI algorithms locate the targets and identify the weapons in the live video feed being viewed by the commanders. Suddenly, the pilot sees a dot flashing on the far horizon through his helmet-mounted display.
Instantly, two of the four teammates divert toward the location indicated by the flash. The helmet lights up a flight path toward the spot, and the pilot receives new orders scrolling across the display:.
The two UAVs that have flown ahead start coordinating to identify the location of hostile forces in the vicinity of the downed aircraft. A Navy rescue helicopter and medical support vessel are already en route. Meanwhile, with the fighter jet speeding away on a new mission, the two other UAVs supporting the special forces squad shift their network configuration to directly link to the satellite networks now serving the base-station role formerly played by the fighter jet.
The live video feed goes on uninterrupted. The reconfigurations happen swiftly and without human intervention. Warfare has always been carried out at the boundary between chaos and order. Strategists have long tried to suppress the chaos and impose order by means of intelligence, communication, and command and control.
The most powerful weapon is useless without knowing where to aim it. The most carefully constructed plan leads nowhere if it is based on bad intelligence. And the best intelligence is worthless if it arrives too late. The next key enabler is fifth-generation 5G wireless communications. These are sizable and complicated projects, and several different strategies are already becoming apparent.
At Lockheed Martin , we're enhancing standard 5G technologies to connect the many platforms and networks that are fielded by the various branches of the armed services. We call this our 5G. MIL initiative. Earlier this year, in two projects, called Hydra and HiveStar , we demonstrated the feasibility of key aspects of this initiative.
Hydra yielded encouraging results on the interoperability challenge, and HiveStar showed that it was possible to quickly construct, in an area with no existing infrastructure, a highly mobile and yet capable 5G network, as would be required on a battlefield. The new work takes an unusual approach.
It is a collaboration with commercial industry in which technology is transferred from the civilian to the military sector, not the other way around.
Radar, rocketry, and nuclear energy got their starts in military labs, and it took years, even generations, for these technologies to trickle into consumer products. But today, for fundamental technologies such as computing and communications, the sheer scale of private-sector development is increasingly beyond the resources of even the largest national defense agencies. To deploy networks that are sufficiently fast, adaptive, agile, and interoperable, warfighters now have little alternative but to exploit commercial developments.
No wonder, then, that the U. To understand the significance of such a shift, consider how the United States got to this juncture. In 18th-century conflicts, such as the Revolutionary War , the only battlefield sensors were human eyes and ears.
Long-distance communication could take days and could be interrupted if the messengers it relied on were captured or killed. Tactical battlefield decisions were signaled by flags or runners to commence maneuvers or attacks. By World War II, combatants had radar, aircraft, and radios to sense enemy planes and bombers up to 80 miles ahead.
They could communicate from hundreds of miles away and prepare air defenses and direct fighter-interceptor squadrons within minutes. Photoreconnaissance could supply invaluable intelligence—but in hours or days, not seconds.
Today, the field of battle is intensively monitored. There are countless sensors on land, sea, air, space, and even in cyberspace. Jet fighters, such as the F, can act as information-processing hubs in the sky to fuse all that data into a single integrated picture of the battlefield, then share that picture with war fighters and decision makers, who can thus execute command and control in near real time.
Three Lockheed Martin military aircraft, built in different eras, have different communications systems designed to make it hard for an adversary to detect a transmission. In a project called Hydra, engineers used electronic systems called open-system gateways to enable the three to communicate freely. From the top, the aircraft are the F, the U-2S, and the F Lockheed Martin. At least, that's the goal. The reality often falls short. The networks that knit together all these sensors are a patchwork.
Some of them run over civilian commercial infrastructure and others are military, and among the military ones, different requirements among the different branches and other factors have contributed to an assortment of high-performance but largely incompatible communication protocols. Messages may not propagate across these networks quickly or at all. Here's why that's a problem. Say that an F detects an incoming ballistic missile. The aircraft can track the missile in real time.
But today it may not be able to convey that tracking data all the way to antimissile batteries in time for them to shoot down the projectile. That's the kind of capability the 5G.
MIL initiative is aiming for. There are broader goals, too, because future battlefields will up the ante on complexity. Besides weapons, platforms, and gear, individual people will be outfitted with network-connected sensors monitoring their location, exposures to biochemical or radioactive hazards, and physical condition. To connect all these elements will require global mesh networks of thousands of nodes, including satellites in space. The networks will have to accommodate hypersonic systems moving faster than five times the speed of sound, while also being capable of controlling or launching cyberattacks, electronic warfare and countermeasures, and directed-energy weapons.
Such technologies will fundamentally change the character and speed of war and will require an omnipresent communications backbone to manage capabilities across the entire battlefield. The sheer range of coordinated activities, the volume of assets, the complexity of their interactions, and their worldwide distribution would quickly overwhelm the computing and network capabilities we have today.
The time from observation to decision to action will be measured in milliseconds: When a maneuvering hypersonic platform moves more than 3. Our 5G. MIL vision has two complementary elements. One is exemplified by the opening scenario of this article: the quick, ad hoc establishment of secure, local networks based on 5G technology. The goal here is to let forces take sensor data from any platform in the theater and make it accessible to any shooter, no matter how the platform and the shooter each connect to the network.
Aircraft, ships, satellites, tanks, or even individual soldiers could connect their sensors to the secure 5G network via specially modified 5G base stations. They could also share data via military tactical links and communications systems. In either case, these battlefield connections would take the form of secure mesh networks.
In this type of network, nodes have intelligence that enables them to connect to one another directly to self-organize and self-configure into a network, and then jointly manage the flow of data. Inside the hybrid base station would be a series of systems called tactical gateways, which enable the base station to work with different military communication protocols.
Such gateways already exist: They consist of hardware and software based on military-prescribed open-architecture standards that enable a platform, such as a fighter jet made by one contractor, to communicate with, say, a missile battery made by another supplier.
The second element of the 5G. MIL vision involves connecting these local mesh networks to the global Internet. Such a connection between a local network and the wider Internet is known as a backhaul. In our case, the connection might be on the ground or in space, between civilian and military satellites.
The resulting globe-spanning backhaul networks, composed of civilian infrastructure, military assets, or a mixture of both, would in effect create a software-defined virtual global defense network. The software-defined aspect is important because it would allow the networks to be reconfigured—automatically—on the fly. That's a huge challenge right now, but it's critical because it would provide the flexibility needed to deal with the exigencies of war.
At one moment, you might need an enormous video bandwidth in a certain area; in the next, you might need to convey a huge amount of targeting data.
Alternatively, different streams of data might need different levels of encryption. Automatically reconfigurable software-defined networks would make all of this possible. The military advantage would be that software running on the network could use data sourced from anywhere in the world to pinpoint location, identify friends or foes, and to target hostile forces.
That means no matter how many thorium nuclei you pack together, they will not on their own start splitting apart and exploding. If you want to make thorium nuclei split apart, though, it's easy: you simply start throwing neutrons at them. Then, when you need the reaction to stop, simply turn off the source of neutrons and the whole process shuts down, simple as pie.
Here's how it works. When Th absorbs a neutron it becomes Th, which is unstable and decays into protactinium and then into U That's the same uranium isotope we use in reactors now as a nuclear fuel, the one that is fissile all on its own. Thankfully, it is also relatively long lived, which means at this point in the cycle the irradiated fuel can be unloaded from the reactor and the U separated from the remaining thorium.
The uranium is then fed into another reactor all on its own, to generate energy. The U does its thing, splitting apart and releasing high-energy neutrons. But there isn't a pile of U sitting by. Remember, with uranium reactors it's the U, turned into U by absorbing some of those high-flying neutrons, that produces all the highly radioactive waste products.
With thorium, the U is isolated and the result is far fewer highly radioactive, long-lived byproducts. Thorium nuclear waste only stays radioactive for years, instead of 10,, and there is 1, to 10, times less of it to start with.
Researchers have studied thorium-based fuel cycles for 50 years, but India leads the pack when it comes to commercialization.
In , India's nuclear regulatory agency issued approval to start construction of a megawatts electric prototype fast breeder reactor, which should be completed this year.
In the next decade, construction will begin on six more of these fast breeder reactors, which "breed" U and plutonium from thorium and uranium.
Design work is also largely complete for India's first Advanced Heavy Water Reactor AHWR , which will involve a reactor fueled primarily by thorium that has gone through a series of tests in full-scale replica.
The biggest holdup at present is finding a suitable location for the plant, which will generate MW of electricity. Indian officials say they are aiming to have the plant operational by the end of the decade.
China is the other nation with a firm commitment to develop thorium power. This molten salt blanket becomes less dense as temperatures rise, slowing the reaction down in a sort of built-in safety catch.
This kind of thorium reactor gets the most attention in the thorium world; China's research program is in a race with similar though smaller programs in Japan, Russia, France, and the U.
There are at least seven types of reactors that can use thorium as a nuclear fuel, five of which have entered into operation at some point. Several were abandoned not for technical reasons but because of a lack of interest or research funding blame the Cold War again.
So proven designs for thorium-based reactors exist and need but for some support. Well, maybe quite a bit of support. One of the biggest challenges in developing a thorium reactor is finding a way to fabricate the fuel economically.
The options for generating the barrage of neutrons needed to kick-start the reaction regularly come down to uranium or plutonium, bringing at least part of the problem full circle. And while India is certainly working on thorium, not all of its eggs are in that basket.
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