let me finish tonight roughly where i began tonight. i don't really like negative political ads. can you tell. when it gets near election time and they start running them, i get depressed. some like indictments, they're usually black and white, the creepy voice of the announcer, sometimes sarcastic, sneering. other times whispering. he's giving you the dirt. the newspaper clippings, the mocked up headlines that flash on your screen to give the attack ads some authority -- hey, this guy belongs in jail. this is criminal stuff. how awful? how does this guy live with himself? does he have a family, how does he get up in the morning or go to bed at night sbog corrupt. we're supposed to have a couple of reactions. second, we're supposed to forget all about the ad once the election is over and go on believing the government is in good hands. we're supposed to believe in all those -- we've elected to run

the country even when we remember they spend weeks watching and listening to the disgusting tv ads and the state assembly people and the judges and city council people, u.s. senators and members of congress. after they watched so much of this stuff, we don't feel good about politics at all. neither do we forget all about what we've seen in the ads after the election is over. now we remember face after face, familiar sounding name after familiar-sounding name, as the people who are now running the government those ads we get at election time are the previews of coming attractions like you see in a movie theater what's coming in a political office near you. i don't like politics as prosecution. one of the people like you, maybe, who thinks politics can bring out the best in us. good people to lead us. sometimes what we're facing right now, the best people. these ads, the nasty tv ads you see, how about the next time you catch one, you pay attention to

which candidate is paying for the ad. the ad that says, i'm joe blow and i approve this message? how about voting against that guy next time. that's hardball for now. thanks for being with us. up next, "future earth," addicted to power. a ship carrying gas explodes in boston harbor. a chinese den collapses, unleashing a 50-foot tidal wave. the east coast is plunged in to days of darkness by a blackout. and in london, a train carrying nuclear waste crashes. enveloping the city in a radio active cloud. these nightmare scenarios could happen. because we have become addicted

to energy. and like any addict, we don't care how we get our fix, but now the consequences could lead to global disasters. addicted to power -- we are. across this globe of ours, the race is on to plug the growing gap between diminishing energy supply and soaring demand. meanwhile to avoid choking on the carbon-based energy we burn, we're engaged in a worldwide search, not a gold rush, but a power rush. to be first to find and first to develop new energy sources that are clean, green, and, yes, inexpensive. >> what will happen to the world 100 years from today is actually

fundamentally quite frightening. many people don't appreciate just how frightening it is. so we need a new industrial revolution. >> america's secretary of energy, professor steven chu, is a nobel prize-winning physicist. he deals in science fact. >> we had incredible energy resources. so we built an energy structure and a set of habits based on abundant energy for 200 years. >> rapid global industrialization has helped create mobile prosperity. but it is also addicted the world to fossil fuels now poisoning and warming our planet. in the next 20 years, we'll need 60% more power to satisfy the new emerging global economist. but what will be the source of that new power?

fossil fuels? nuclear? hydroelectric? each has advantages and risks. another. >> our generation's response to this challenge will be judged by history. for if we fail to meet it boldly, swiftly, and together, we risk consigning future generations to an irreversible catastrop catastrophe. >> oil is the fossil fuel that drives the world's economy. oil is black gold, dirty, but precious. the world is hooked. >> you look back at the history of the 20th century, in some ways, it's a history in oil. it's been a driver of geopolitics, it's ban driver of military policy for a lot of countries. and at the same time, it's been the sort of fuel for the engine

of economic growth. >> the u.s. is a society built on oil. transport, food, medicine, all inextricably linked to oil with a huge $1 trillion infrastructure built to support it. but the world's oil reserves are fast running out. we may already have passed the peak of production. our reliance on oil also makes it a potent political tool. when use in the past and most likely to be used again in the future. u.s. government advisor and global energy security expert understands the dangers. >> we remain hostage to a

relatively wide range of possibilities for oil to be disrupted, any of which could cause problems of world trade or cause economic growth to come to a halt. >> disruption of supply by accidents and even terrorist attacks is now the global economy's achilles heel. 80% of the world's oil passes through tankers through six narrow channels known as choke points. the strait in turkey connects russia, the world's second biggest oil exporter, with the rest of the world. >> it's probably the most likely single point in the world that would cause an oil shock wave, globally. if they were closed, 7% of the oil that every day is on the ocean and on the pipelines would cisse to be shipped. >> disruption of oil supply

could throw the world in to turmoil. turkey, 2015. a tanker loaded with 150,000 tons of russian crude oil navigates through the channel which is at its narrowest point, 2,200 feet wide. iran, russia's main export competitor is suspicious with russia's links to the west and oil deals in the caspian sea. a terrorist group with iranian sympathy plows a suicide boat loaded with explosives in to the russian tank. the sunken tanker blocks the

channel to all traffic. markets react instantly to the news. >> as soon as it's closed, phones ring, oil prices rise immediately. >> but there's worse news -- africa's biggest oil producer, nigeria, is in turmoil after election results are contested. >> oil has been systematically disrupted in nigeria for political gain for the entirety of the last decade. the disruption would provide a great opportunity for them to amplify the impact of their disruptions. >> nigerian militants capitalize on the oil market collapse by disrupting the oil wells, another 5% of the global supply is lost. with 12% of oil supplies disrupted, prices spiral out of control. after three days, motorists begin to panic, buying gasoline. people are forced to seek other

means of transport. as oil prices increase, truckers protest, blockading roads. but the price keeps rising. >> we could be well above $130, $140 by the end of it. those are the kinds of prices that triggered the last recession. >> it takes four weeks to reopen the channel. it's too late. the world plunges to global recession. >> is the united states prepared to deal with another oil shock? no. is the world economy prepared to deal with an oil shock? the answer is no. >> until we can develop alternative fuels for transportation, the world remains at the mercy of the oil markets. weaning ourselves off of fossil fuels is a slow and expensive business, but there's a fossil fuel that's cheap and plentiful, natural gas. [ cellphone rings ] [ katie ] hey.

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>> our existing forms of energy are running out. and they're polluting and warming our planet. are we heading for a crisis point? in an energy-starved world, natural gas is becoming an increasingly attractive alternative for generating energy. it emits half the carbon of coal and 1/3 the carbon for oil. demand for gas is growing. but in its gaseous state, it's expensive to transport, so it's compressed 600 times, then cooled becoming a liquid gas known as lmg. one giant tanker can hold 36

million gallons of lmg in pressurized tanks, enough to power a city like boston, massachusetts for a week. but a tanker is extremely dangerous. firefighters train for an lmg accident. the freezing liquid doesn't burn, but as it pours out of a ruptured container, it vaporizes and spreads uncontrollably. now the gas cloud becomes highly volatile. once ignited, it burns at 2300 degrees fahrenheit, twice as hot as gasoline. >> if you have a large gas united, what's going to stop you

initially getting too close to the fire. you can feel it on your face now. >> the surrounding air becomes so heated, firefighters can't get close. this is just a small training fire, an accident in a busy port would involve millions of gallons of lmg. >> that would be a potential bomb. i would imagine a firefighter's worst nightmare or something like that to happen in the middle of a city. >> at present, there are 11 ports that handle lmg hankers in the u.s. the one in boston is in the heart of the city. candace kelshaw is an expert in maritime terrorism. her research has revealed that tankers could become a target for future terrorist attacks. >> the most likely scenario is that you would have an officer

that has quite a ship, is familiar with the environment at sea and has become radicalized and now has a suicide mission planned. >> a suicide mission in a city harbor would be cat trosk, affecting tens of thousands. m.i.t. professor and former chairman of the massachusetts port authority, james fey, published the report outlining the dangers of an explosion in boston harbor. >> you just have to look at the population of people out of doors in a space like this. anyone within half a mile of the waterfront could be hurt. >> 2015 -- boston harbor.

1,000-foot tanker carrying 33 million gallons of lmg sales at five knots, just over walking distance, in to boston harbor. close by is downtown, east boston, logan airport, and charlestown, all densely populated. as is normal, when an lmg tanker approaches the harbor, no other traffic is allowed on the water. security is tight. >> helicopters are overhead. the roads are closed on the side. the bridges are closed. there's a moving security to either side of the vessel. >> the massive security presence is looking the wrong way. a radicalized crew member has planted a bomb next to one of the lng tanks. >> it doesn't take very much to blast a very big hole in the

side of a tanker. >> the bomb's explosion splits the side of one of the tanks and the lmg pours out. it ignites, rupturing the other tanks. >> once that occurred, you're looking at what will be the most catastrophic thing, breach of the tanks. >> thousands of tons of liquid gas pour into the water. >> the lng comes in contact with what it would regard as red hot liquid. it is so cold compared to the wat water. >> the lng expands. winds with a vapor cloud towards

downtown boston. the cloud erupts in a fireball 1,000 feet high. that's thermal radiation wave pulses through the city. this isn't fire, but heat from the explosion so hot that it ignites anything in its path. >> that circle identifies the region within which there would be harmful radiation to anyone on the shore. >> the gas would burn for 50 minutes and it would be long enough to devastate the city. >> it's an enormous fire. we've never seen anything like that, i hope we never do. >> as long as lmg is shipped into harbors like in boston, the threat remains all too real. >> trying to run this kind of business and all crowded ports where a lot of people live nearby has got to go. we've got to get the danger

offshore and then there's no problem. >> while this would address the problem of safety, it does nothing to change the fact that gas is a fossil fuel and harmful to the environment. planners are going back to the future and looking once more at nuclear power. national car rental? that's my choice.

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as the threat of global warming increases, there's growing pressure to reduce carbon emissions forcing government to reconsider nuclear energy. >> right now if i look at technology for coal and technology for nuclear and environmentally its impacts, while only one has no carbone

missions so i would quite frankly favor nuclear. it is estimated that over 500 nuclear plants and 30 countries will be in operation by 2025 despite the long shadows that hang over nuclear power. in 1979, a partial meltdown at the three-mile island nuclear power plant in pennsylvania led to the release of radio active gases. then, in 1986, a disastrous accident in a soviet power plant at chernobyl led to the deaths of thousands. this confirmed the worst fears of the anti-nuclear lobby. but the tide is turning. energy planners believe the nuclear energy has learned its nuclear lessons. >> we now know how to operate power plants in a safe way. the designs are far safer than

chernobyl and far safer than the three-mile island design. >> but one problem persists -- the safe disposal of the nuclear fuel rods which remain lethal for centuries. >> if this rod had been just withdrawn from a reactor, it would be so intense intensely radioactive that my survival rate would be less than 1/30th of a second. >> john large is a world renowned nuclear scientist. >> the unsolved problem is the back end of the nuclear process -- what do you do with the intensely radioactive fuel once it's served its purpose in the reactor? >> nuclear waste is transported in specially designed flasks that are tested to the limit. tests like these prove the flasks could survive a 100

mile-per-hour train collision. they are also designed to withstand a fire burning at 1400 degrees fahrenheit for 30 minutes with the fuel rods shielded in water-filled compartments. but according to john large, that may be their fatal flaw. >> i'm concerned about the thermodynamic performance of this. if it's in a fire, there's no way of venting the excess pressure buildup that occurs. this is full of water so it turns into a pressure cooker. >> such conditions could occur in a railway tunnel fire. july 18, 2001 -- baltimore, maryland. population 600,000. a 60-car freight train laidened with flammable chemicals derailed inside the howard street tunnel resulting in an

inferno. physicist dr. marvin reznikov investigates what could have happened if the nuclear blasts had been involved in the tunnel fire. >> some were glowing reddish orange. that would tell us that the fire would have to be around 1500 or 1600 degrees fahrenheit. >> nuclear waste flasks can understand temperatures like that for an hour. the baltimore tunnel fire lasted for five days. john lars is calculating what could have happen if destruction struck one of the world's biggest cities. london, england. 2015. spent nuclear fuel from the reactor is en route to the world's largest reprocessing

plant in england. it makes a routine rail journey through the heart of london. the train approaches a half-mile-long tunnel north of the city center. in the darknd, the badly maintained track buckled, derailing the train. fortunately, the protective flasks are intact. but before the train's crew can raise the alarm, a freight strain laidened with oil rumbles into the tunnel, plowing head on to the derailed train. the spark ignites the spilled fuel.

the tunnel's brick walls act like a furnace, temperatures rise to 2,500 degrees fahrenheit. fire crews assess the radiation levels and know it's time to evacuate. pressure will build up and build up rapidly an hour and a half into the fire would be sufficient to break it and enable the fuel to be broken up released into the atmosphere. >> even though only 1% of the radioactive fuel is likely to be released, it's all it takes to create the deadly plume over london. the weather dictates the number of people exposed, which could be up to 700,000.

there may not be any immediate deaths, but during the next 50 years, thousands of londoners could die as radioactive elements like cesiam and plutonium lead to cancers. sooner or later, spent fuel now stored on site at u.s. nuclear plants will need to be moved, putting american cities at risk. get the growing need to fill the energy gap has forced the nuclear option back on the table. >> i think nuclear power has to play a significant role as we transition to renewables. it's going to take some time. it's part of the mix. >> nuclear power could offer a short term solution. but could we harness the power of the rivers of the world to provide an endless clean source

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i'm lynn berry. here's what's happening. the senate approved a plan to have benefits for families caring for severely wounded veterans. the coast guard says an oil rig that explode in the gulf of mexico this week was carrying 700,000 pounds of diesel fuel and it could spill 8 million barrels of oil per day. now back to "future earth." >> our hunger for carbon-based energy is causing weather changes and altering the air we breathe. meanwhile, the earth mourns, the polls melt, the ocean dries. but there is a green solution to our energy conundrum that happens to be blue -- water. by combining water and gravity, one gets an inexhaustible source

of clean green energy and it's available on every continent, hydroelectric power. >> but the giant dams needed to hold back the water have an environmental cost, producing the flow and damaging the ecosystem downstream. if a dam ever collapses, the death toll could be shocking. in 1975, a 50-foot wave killed 230,000 chinese from the dam. >> a typhoon overwhelmed the dam. you've got to be able to anticipate those storms. make sure they're designed for the extreme loads, especially if you have extreme consequences. >> but despite the risks, china, argentina, congo, india, vietnam, and mexico are all planning massive super dam

projects. this is in western mexico. when it's complete, this hydroelectric dam on the santiago river will be one of the tallest in the world, more than 700 feet high. >> we are installing 750 megawatts of power here, enough to give energy to the city of guadalajara which is 5 million people. >> ensuring a 700-foot high wall of water stays in place is an overwhelming priority for mr. menendez. >> safety is high. we can't allow any minor divisions because we will have two more dams and lit be work as a cascade and it will be a

disaster. >> engineers design dams to meet the most extreme conditions, like a rainstorm that might come only once in 1,000 years. but global warming is forecast to make unpredictable weather more frequent and more extreme. experts now say the world's 45,000 large dams need to be upgraded to protect them from the effects of global warming or the consequences could be dire. china, 2015, the country leads the world in hydroelectric power generation. its population, now 1.4 billion, consumes more energy per day than the united states in a week.

its latest dam is built to withstand a one in 1,000-year flood. an unprecedented category five typhoon strikes, unleashing 80 inches of rain in just 24 hours. debris carried by the rising water blocks the spillway. >> if the dam was not operated properly for this storm, or if the spillway were clogged with debris, you could get more in flow than was ever anticipated. >> with the spillway blocked, the water level rises rapidly. a landslide crashes in to the reservoir, releasing 5,000 tons of earth and rock. 800 million cubic feet of water overtops it dam, sending a massive wave rolling down the

hillside towards the village. a further seven dams are reached by the wake as it streaks downstream. whole communities are washed away. an area the size of los angeles is flooded. hundreds of thousands die. super dams can offer plentiful energy for many countries, but the unpredictability of future weather means there's an added pressure and risk. however our future energy is generated, it will be all for nothing if it can't get to where the power plant can get. the power grid could be the weakness link of all in our future energy supply. ya know, i'm really glad we finally decided to see where raisin bran crunch is made.

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>> we're facing an energy crisis where any disruption to the delicate balance of supply and demand could lead to disaster. even if we can solve this crisis, can we trust the grid to reliably supply us with electricity? america's first grid was created in new york city almost 120 years ago and then rapidly expanded to cover the whole of the east coast. but it's now old and prone to failure as it struggles to cope with ever-increasing demands for energy. >> if we lost electricity

tomorrow, it would be pretty much back to the stone age existence. >> professor tom overbuy is an expert in the workings of the u.s. grid. >> it would be hard to imagine the modern world without electricity because we depend on it for everything we do. when the lights go out, pretty much nothing gets done. >> 180,000 miles of transmission lines have been grafted on to america's ancient infrastructure, to keep the electricity flowing requires constant care. our relentless dependence on electricity means cables can't even be powered down for maintenance -- how do you repair a 500,000-volt line you can't switch off? very carefully. specially designed helicopters allow technicians to work on

live lines. >> you might do it every day. can't get complacent with it. got to think about what you're doing all the time. >> the secret of working on energized cables is to attach yourself to the live lines so that you are grounded. >> put the wand on the wire, the whole helicopter, the people, everything, gets energized to the same potential. >> the team know ifs they make a mistake, it will be fatal. >> aviation in and of itself is not inherently dangerous. it's extremely unforgiving. this is a little more unforgiving than that. >> despite this constant maintenance, the aging grid still fails. august 14, 2003. the cascade of failures plunged

some 55 million people on the eastern seaboard in to the dark. the blackout shuts offices and strands commuters. but within 24 hours, it's over. >> if we don't improve our transmission grid, we're probably looking at more potential blackouts in the future certainly if we have a growing population which we do in growing electric demand. >> the grid must cope with a 33% increase in demand in the next decade alone. but it faces new challenges, extreme weather and fires already cause 40% of all major outages. climate change will bring more intense hurricanes, more floods,

and boosting heat waves. outages of the future could last more than 24 hours. the east coast, 2015. global warming is all too real. the northeast is gripped by a blistering heat wave. high temperatures and increased demand causes transition lines to overheat, bringing power out annals across the grid. >> in a cascading failure, what happens one line trips, it causes an increase flow on the other lines. if another line flips, it causes more and more flow. so eventually you get a cascade. >> the overload ripples through the system, jumping from circuit to circuit until the entire system crashes. the great blackout of 2015 has

begun. new york is hit first. elevators stuck. subways come to a halt. four million commuters are strand in the darkness. after 24 hours of blackout with repairs under way, there's a new disaster -- a massive summer storm sweeps over the eastern seaboard damaging thousands of lines. within 30 minutes, lights go out across ten states, from michigan to vermont and all the way up to canada. by day two, it's clear the northeast grid has suffered significant infrastructure damage. gas stations can't pump fuel, food rots without refrigeration. on day three, in the stifling

heat, millions are forced to abandon their homes. >> you live in a high-rise and it gets hot, you're going to have to leave because it's going to become unliveable inside that building very quickly. open spaces become refugee camps across the northeast. day four, at hospitals, patients die as backup generators run out of fuel. fuel and water is rationed. panic takes hold. looting breaks out. law and order breaks down. thousands of extra grid workers are drafted from texas and the west coast to help restore supply. >> the power grid is not designed to get everyone with the full electric load at the same time. places like hospitals, police station, fire stations get electricity first. then it takes a while to get to the residential neighborhood.

>> as the fixes are made, the power stations restart, and the grid sputters back to life. society gradually returns to normal. but the cost is many lives and billions of dollars lost. the risk of this disaster will be reduced but will require anup graded and smarter grid. but to power this grid of the future, the hunt is on to find a green carbonless source of energy and better ways to deliver it. scientists now believe the holy grail to the energy crisis could lie in re-creating the sun here on earth. national car rental knows i'm picky.

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in the last 100 years, the

use of energy has revolutionized the way we live, but it has also fundamentally changed the planet we inhabit. so we must find new sources, ones that are plentiful, but above all, clean, without carbon emissions. leading the u.s. to revolution is the job of secretary professor chu. >> incredible opportunity to say, all right, we have the greatest research and development and machinery in the world. why not take the opportunity to become the leader in the industrial revolution? >> and solutions exist -- clean abundant energy is available, enough to power the entire world many times over. >> there's plenty of renewable energy around -- five times as much wind available compared to

the total power of demand. the amount of sun height is even more. >> if april is enough to have it on demand, why aren't we using it? green energy though clean, renewable, and abundant is often dependent on the weather. electricity is generated when the wind blows and the sunshine. the solar array in the mojave desert captures 13 hours of sun a day. we have an around-the-clock energy addiction. environmental engineer professor mark jacobson believes that combining a variety of clean energy sources can overcome the problems. >> we want to be able to combine wind and solar as much as possible because they're complementary to each other. if you have wind alone, it won't be as smooth as a conventional

power plant. however, if you combine wind with solar and use hydroelectric to fill the gaps, it's not only smooth, it matches the demand perfectly. >> but there is another challenge for renewable energy, transmission. getting the supply from where it's used to where it's needed. 79% of americans live in cities, thousands of miles away from the windy great plains or the solar arrays of the remote deserts. renewable energy will be need to be carried over vast distances which will be for reknewed technology. >> normal cables have resistance. if we can use superconductors to transfer electricity, we could get a lot more electricity down a cable than we can using traditional technology. >> super conducting cables

approach zero resistance, allowing the traps sigs of far greater electrical loads over much greater distances. they are expensive, requiring rare alloys and are only in the stage. but if successful, they could distribute renewable energy to every corner of the u.s. far further in to the future technology lies in the holy grail of energy production, a technology that uses laser beams to re-create the energy of a star right here onnette. exastronaut and physicist dr. peter weisoff is working on a new kind of nuclear power, fusion. >> it's a carbon-free source of energy, it's a limitless source of energy. the major constituent of the fuel is found in seawater which

is abundant here on the earth. >> current nuclear power depends on physician, splitting atoms. they're working to prepare to increase atoms to 180 million degrees fahrenheit. these conditions are only found inside stars, enabling them to burn brightly for millions of years. the key is a laser, the biggest in the world, over half a mile long focused on a minute target. >> it all happens in a few billionths of a second. this is a short laser pulse. it goes in and heat this is target to extreme conditions. all the matter collides together. reaches a temperature of 100 million degrees, we get the fusion process to occur and it's all done in an instant. >> the energy released is harnessed by heating liquid salt, which produces