Trump saved this old-fashioned lightbulb. Biden’s now phasing it out.

The energy price spikes of the 1970s drove consumers, businesses and government to calculate opportunities for energy efficiency — investments, practices, and regulations to avoid some of the energy costs associated with particular products or services. Those calculations ran counter to a lot of engrained practices, and the friction between business and government is a feature of energy and environment policy discussions. Now, energy efficiency decisions — whether involving building practices, appliance efficiency, or vehicle mileage and emissions standards — are a complex mix of government regulation and market behavior.