Save for later Print Download Share LinkedIn Twitter Significant gas-to-coal switching is apparently taking place, especially once gas prices moved well above $3 per million Btu. With Henry Hub prices averaging $3.78/MMBtu in July — up more than $2/MMBtu from a year earlier — US gas-fired generation declined 8.8% year over year, accounting for 41.8% of utility-scale generation during the month, the US Energy Information Administration reported last week.