Tuesday afternoon, Secretary of the Interior Ken Salazar announced that the Bureau of Land Management will hold competitive lease sales of nearly 7,500 acres of land in the Powder River Basin.

Under that land lies an estimated 758 million tons of coal. Estimates of the royalties and other income generated by the sale and eventual mining of that coal range from $13 billion to more than $21 billion over the life of the leases. Wyoming will receive 48 percent of that money.

What’s more, the four parcels that will be auctioned this spring and summer are only the first of a dozen or more similar tracts to be auctioned over the next three years as the United States and the rest of the world work to keep up with the growing demand for electricity.

Coal is a controversial fuel for a variety of reasons. Underground mining is prone to explosions and collapses that result in deaths, and strip mining changes the landscape and sometimes results in water pollution. Burning coal affects air quality, producing greenhouse gases that many scientists believe are changing our climate.

But other methods of generating electricity raise concerns also. The issues regarding nuclear plants are particularly obvious right now, and the economic and environmental costs of our continuing thirst for oil were revealed last summer in the Gulf of Mexico. Some dream of the day when alternative energy sources, such as wind and solar generation, replace fossil and nuclear fuels, but those technologies all have shortcomings and environmental impacts of their own.

In the last presidential campaign, Barack Obama talked of coal eventually being phased out by alternative sources of energy, raising the ire of many in Wyoming, because our state’s economy is so closely dependent on development of coal and other energy resources. Reality, however, as it usually does, trumps political rhetoric. Consequently, for the foreseeable future, coal will continue to be a major source of energy for the nation, and Wyoming will continue to profit from its production.

So far, those profits have served to allow the state to build and improve its infrastructure while keeping taxes relatively low, and, at the same time, adding to a permanent trust fund that can provide for future concerns.

For even though coal is indispensable right now, technology sometimes surprises us, and the technological advance that makes coal less important might be just over the horizon.

So while Secretary Salazar’s announcement is welcome economic news for the state, it should be greeted cautiously. We should continue to invest the benefits of coal sales wisely, not just for the present, but for what might be coming in the future.