filling station in Seoul, South Korea. Photograph: Kim Hong-Ji/Reuters

Hydrogen can also power vehicles, but in a different way than it would heat houses. Instead of being burned, the hydrogen reacts with oxygen inside a device called a fuel cell. Electricity and water are produced. The electricity runs the car, the water drips from the exhaust pipe.



An attempt to switch to hydrogen vehicles in the 1990s was thwarted byelectric cars, which store their energy in an onboard battery. But a new push for hydrogen vehicles is coming from Asia. China, Japan and South Korea have all set ambitious goals to have millions of hydrogen-powered vehicles on their roads by 2030.



Toyota and Hyundai are both offering hydrogen vehicles in the UK, but there are currently less than 20 hydrogen fillingThe National Hockey League released Thursday its composite 2013-14 preseason schedule. The 16-day, 104-game slate opens on Saturday, Sept. 14.

The people of Stirling-Rawdon, Ontario, winners of the Canada-wide Kraft Hockeyville competition, will celebrate the grand prize on the opening day of the schedule when the Washington Capitals and Winnipeg Jets visit their community. The Capitals and Jets will contest the first game of the preseason in nearby Belleville, at Yardmen Arena.

The schedule features several other contests that will be played outside NHL venues, in Baltimore, Md. (Boston vs. Washington, Sept. 17); Barrie, Ontario (NY Islanders vs. Ottawa, Sept. 29); Brooklyn, N.Y. (New Jersey vs. NY Islanders, Sept. 21); Estero, Fla. (Florida vs. Tampa Bay, Sept. 26); Las Vegas, Nev. (Los Angeles vs. NY Rangers, Sept. 27 and Los