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A recycling lottery

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Getting people to recycle isn’t always easy.  The bottled beverages we buy at the supermarket often require a small deposit that we can get back by recycling the bottle, but often, we just don’t.

Researchers from the University of British Columbia tested the idea of giving people returning bottles a small chance of winning a big cash prize instead of a 10-cent deposit return.  The result was that people recycled 47% more bottles.

Changing how we reward recycling made a big difference.  When given a choice between a guaranteed return and a possible large reward, many chose the lottery option.  When people were randomly assigned to one type of reward or the other, those in the lottery group brought in almost three bottles for every two returned by the other group.

This isn’t a new idea.  Norway has a recycling lottery, and their bottle return rate is close to 100 percent.  The way it works there is there are reverse vending machines in grocery stores all over the country.  The revenues generated by the machines is split in four ways:  34.5% of the gross revenue goes to the Red Cross; 35% goes to the people who bring in their bottles in the form of winnings in the lottery; 9.75% goes to the stores for managing the machines and the lottery; and 10.75% goes to the operating company of the Recycling Lottery.

The Canadian experiments demonstrate that a recycling lottery could be effective in more places than Norway.  However, it shouldn’t completely replace the guaranteed refund option, since some people depend on it for income.

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How lottery-style bottle returns could transform recycling

Photo, posted July 9, 2011, courtesy of Mr.TinMD via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A giant underground battery

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Two up-and-coming energy technologies are coming together near a tiny town in central Utah.  Outside of the town of Delta, population 3,600, two caverns, each as deep as the Empire State Building, are being created from an underground salt formation to be used to store hydrogen gas.  The gas will be used as a fuel in a new electricity generation plant.

The plant will replace an aging local coal-fired power plant.  The new plant will burn a mixture of natural gas and hydrogen – green hydrogen produced without emitting greenhouse gases. To produce the hydrogen, the facility will operate 40 giant electrolyzers that will use excess solar and wind power generated at times of low demand to split water molecules into hydrogen and oxygen.

The caverns were created by a process called solution mining in which high-pressure water is pumped down into salt deposits that are dissolved. The resulting caverns are 200 feet in diameter and 1,200 deep and lie 3,000 to 4,000 feet below the surface.  Hydrogen cannot escape through the thick salt layers.

The amount of energy that can be stored in the form of hydrogen fuel in these caverns is massive – far more than all the battery storage installed in the U.S. to date.  Chevron has a majority stake in one of the projects and will supply the natural gas.  The facility is expected to go online in 2025.

While this will produce far fewer emissions than existing coal plants, it is not carbon-free.  Currently, turbine technology cannot operate with pure hydrogen fuel.  The Delta plant will run on only 30% hydrogen.  The hope is that turbine technology will improve in the future and permit operation on pure hydrogen.

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A Huge Underground Battery Is Coming to a Tiny Utah Town

Photo, posted September 9, 2013, courtesy of Scott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar thermochemical hydrogen

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For decades, there has been talk of the hydrogen economy in which hydrogen would take the place of fossil fuels in a wide range of domestic and industrial applications.  Over time, hydrogen’s potential advantages in some applications have diminished but it is still seen as perhaps the most promising way to decarbonize long-distance truck, ship, and plane transportation as well as many heavy-duty industrial processes.

Hydrogen is the most common element in the universe, but here on Earth, it is tightly bound up in chemical compounds, notably water and hydrocarbons.  Extracting hydrogen from these compounds takes lots of energy.  To date, most hydrogen is produced from fossil fuel sources, resulting in carbon dioxide emissions.  So-called green hydrogen is made by splitting up water into its component elements.

Getting hydrogen from water generally uses electrolysis, which requires lots of electrical power.  That is why it isn’t the standard way to produce hydrogen; it costs too much to pay for all that power.

MIT scientists have been developing a process to make solar thermochemical hydrogen, or STCH.  STCH uses the sun’s heat to split apart water and no other energy source.  An existing source of solar heat drives a thermochemical reaction in which a heated metal surface grabs oxygen from steam and leaves hydrogen behind.  MIT did not invent the concept; their efforts are to make it practical.

Previous STCH designs were only capable of using 7% of incoming solar heat to make hydrogen.  The MIT process may be able to harness up to 40% of the sun’s heat and therefore generate far more hydrogen. 

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MIT design would harness 40 percent of the sun’s heat to produce clean hydrogen fuel

Photo, posted August 23, 2017, courtesy of Evan Lovely via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)