Lately we have heard a lot about the risks associated with the way we produce and use energy. We worry that producing natural gas by fracturing underground shale formations will contaminate our groundwater, or that American nuclear power plants might be susceptible to a Fukushima-type disaster.

We should worry about these risks. They are an important part of the cost of producing and delivering energy, a cost that is sometimes shifted to society rather than borne by the energy producer. Unfortunately, however, we rarely look at these risks in comprehensive and clear-headed ways. Instead, we look at them through the prism of the most recent accident. In so doing, we turn a blind eye to the (sometimes greater) risks associated with the alternatives.

This is a problem because our energy priorities are set mostly by the market, and the market has already spoken. Private companies (for the most part) decide which electric generation technologies in which to invest, and cost is a key driver of that investment. Consequently, about half the electricity we consume nationally comes from coal-fired power plants, while nuclear and natural gas-fired power plants together comprise another 35 percent of the total. These three technologies dominate our electric generation mix, in part because traditionally they have been cost-competitive and reliable.

Renewables like wind and solar power are becoming more cost-competitive all the time, but they remain relatively more expensive alternatives in most locations. In addition, regulators and grid operators are finding that it is difficult to integrate large quantities of renewable power into the electric grid while maintaining reliability of supply.

Regulators and the renewable power industry are working to address these problems, but renewable electricity is not yet functionally equivalent to these more traditional base load resources. What this means is that if we turn away from gas-fired or nuclear power, we make a de facto choice to rely more on coal-fired power.

This matters because the health and environmental costs imposed by coal-fired power dwarf those associated with shale gas or nuclear power. According to a recent Harvard Medical School study, coal is responsible for tens of thousands of premature deaths each year; indeed, if we were to monetize these health and environmental costs, they would more than double the price of electricity.

Many of these costs do not get factored into the price of coal-fired electricity. For example, respiratory illnesses caused by the inhalation of fine particles or toxins from coal-fired power plants often don't manifest until decades after the harmful particles were inhaled. Tracing the cause of illness back to a particular coal-fired power plant is next to impossible. And the traceability problem is even more difficult when we consider the climate impacts of carbon emissions.

By contrast, if my well water is contaminated by a gas producer, or if I am harmed by radiation released from a nuclear power plant, it will be much easier to trace my injuries to their source. This means that the natural gas producer or nuclear power plant owner faces a real liability risk, one he has an incentive to guard against, and one which is more likely to be reflected in his liability insurance costs.

That is not to say that we shouldn't regulate the risks posed by shale gas production or nuclear power production. To the contrary, we should learn from the ongoing studies of hydraulic fracturing and from the Fukushima nuclear accident in order to improve our regulation of these forms of energy production.

However, in so doing we are focusing on health and environmental risks that pale in comparison to the enormous risks we tolerate from coal-fired power production every day. Wouldn't it make sense, then, to devote more of our regulatory attention to reducing these larger, better understood costs of coal?