Reliable electricity is something many of us take for granted. From simple light switches to the iPhones that connect us to the rest of the world, we don’t spend much time wondering whether the power will work when we need it.

Thankfully, reliable power is not something national leaders are taking lightly. Department of Energy Secretary Rick Perry recently called for a report on the reliability of the U.S. electric grid. Like many others, including us, Secretary Perry is concerned federal and state policies may be endangering our electricity grid. The report he commissioned is expected to underscore a number of challenges facing our electricity grid and to offer guidance to policymakers as they work to ensure that changes to the grid don’t jeopardize its reliability.

Much of Perry’s concern stems from the erosion in recent years of the U.S. coal-fired electric generating fleet. Data shows that a third of the nation’s coal fleet currently has either retired or has announced plans to shut down. These shutdowns are due in large measure to federal regulatory policies aimed at reducing the use of coal by electric utilities. In Ohio, 58 coal-fired electric generating units have already shut down or announced plans to close, representing well over half of the state’s coal fleet. Other states tell a similarly troubling story.

In past years, the U.S. electricity grid has relied on a diverse mix of electricity sources such as coal, nuclear, natural gas and renewables. A significant part of this diverse mix has been baseload sources of power, such as coal-fired power plants, that can operate 24 hours a day, seven days a week. As state lawmakers on committees of jurisdiction over energy and natural resources, we strongly support the use of coal as part of Ohio’s energy mix. Even with recent plant shutdowns, coal provides more than half of our state’s electricity and helps to keep electricity prices lower than the national average.

Grid operators like PJM Interconnection, which serves Ohio, point out that without the coal fleet, the grid is less resilient. This means it is less able to withstand events like the Polar Vortex of 2014 and natural gas infrastructure outages. Coal-fired power plants have dependable supplies of fuel on hand, with each plant having a stockpile of 85 days’ worth of fuel. This is different from other sources of electricity, like natural gas power plants, which rely on a network of pipelines to deliver their fuel on an as-needed basis. Coal plants’ onsite fuel supplies have proven critical to protecting grid reliability in recent years, as coal was one of the few energy sources capable of delivering uninterrupted power to regions impacted by the extreme cold.

In the same way that diversifying an investment portfolio reduces risk to a nest egg, a healthy and diverse mix of electricity sources that includes coal, natural gas, nuclear and renewables is part of a winning formula for reducing the risk of power outages. As our leaders make decisions about the electric grid, we encourage them to keep in mind that Ohio and the nation still need the coal fleet.

(Hoagland, R-Mingo Junction, represents Ohio’s 30th Senate District, and Thompson, R-Marietta, represents Ohio’s 95th Ohio House District.)