Extreme cold and snowy conditions are straining power grids around the country.

Texans seem to be bearing the brunt of the outages with more than 4 million homes and businesses starting the day Tuesday without power. Texas has its own power grid and some are questioning why it hasn't been able to handle the demand.

Here & Now's Peter O'Dowd speaks with Daniel Cohan, a professor at Rice University in Houston who studies air, climate and energy.