In terms of energy output, per unit of capital cost, for energy-producing hardware, shale technology has improved by some 500 percent during the past five years; wind turbines, solar cells, and lithium batteries have improved as well, but far less spectacularly. Further, efficiency gains in alternative-energy technologies are slowing, while shale technology shows few signs of a slowdown. Such trends refute the belief that tech progress is bypassing hydrocarbons.