Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

fuel cell car. Instead of choking on the toxic fumes billowing from the back, all you see are colorless, odorless droplets of water.
    “ You put your hand over the exhaust pipe and the only thing coming out is water. That was such a cool feeling,” observed Mike Schwabl, who test-drove the Equinox for ten days.
    Fuel cell technology is nothing new. The basic principle was demonstrated as far back as 1839. NASA has used fuel cells to power its instruments in space for decades. What is new is the determination of car manufacturers to increase production and bring down costs.
    Another problem facing the fuel cell car is the same problem that dogged Henry Ford when he marketed the Model T. Critics claimed that gasoline was dangerous, that people would die in horrible car accidents, being burned alive in a crash. Also, you would have to have a gasoline pump on nearly every block. On all these points, the critics were right. People dodie by the thousands every year in gruesome car accidents, and we see gasoline stations everywhere. But the convenience and utility of the car are so great that people ignore these facts.
    Now the same objections are being raised against fuel cell cars. Hydrogen fuel is volatile and explosive, and hydrogen pumps would have to be built every few blocks. Most likely, the critics are right again. But once the hydrogen infrastructure is in place, people will find pollution-free fuel cell cars to be so convenient that they will overlook these facts. Today, there are only seventy refueling stations for fuel cell cars in the entire United States. Since fuel cell cars have a range of about 170 miles per fill-up, it means you have to watch the fuel meter carefully as you drive. But this will change gradually, especially if the price of the fuel car begins to drop with mass production and advances in technology.
    But the main problem with the electric car is that the electric battery does not create energy from nothing. You have to charge the battery in the first place, and that electricity usually comes from a coal-burning plant. So even though the electric car is pollution free, ultimately the energy source for it is fossil fuels.
    Hydrogen is not a net producer of energy. Rather, it is a carrier of energy. You have to create hydrogen gas in the first place. For example, you have to use electricity to separate water into hydrogen and oxygen. So although electric and fuel cell cars give us the promise of a smog-free future, there is still the problem that the energy they use comes largely from burning coal. Ultimately, we bump up against the first law of thermodynamics: the total amount of matter and energy cannot be destroyed or created out of nothing. You can’t get something for nothing.
    This means that, as we make the transition from gasoline to electricity, we need to replace the coal-burning plants with an entirely new form of energy.
    NUCLEAR FISSION
    One possibility to create energy, rather than just transmit energy, is by splitting the uranium atom. The advantage is that nuclear energy does not produce copious quantities of greenhouse gases, like coal-and oil-burning plants, but technical and political problems have tied nuclear power inknots for decades. The last nuclear power plant in the United States began construction in 1977, before the fateful 1979 accident at Three Mile Island, which crippled the future of commercial nuclear energy. The devastating 1986 accident at Chernobyl sealed the fate of nuclear power for a generation. Nuclear power projects dried up in the United States and Europe, and were kept on life support in France, Japan, and Russia only through generous subsidies from the government.
    The problem with nuclear energy is that when you split the uranium atom, you produce enormous quantities of nuclear waste, which is radioactive for thousands to tens of millions of years. A typical 1,000-megawatt reactor produces about thirty tons of high-level nuclear waste after one year. It is so radioactive that it literally glows in the dark, and has to be stored in special cooling ponds. With about 100 commercial reactors in the United States, this amounts to thousands of tons of high-level waste being produced per year.
    This nuclear waste causes problems for two reasons. First, it remains hot even after the reactor has been turned off. If the cooling water is accidentally shut off, as in Three Mile Island, then the core starts to melt. If this molten metal comes into contact