DOE efficiency standard changes and compliance dates for water heaters, furnaces, dishwashers, washers, dryers, refrigerators, ceiling fans, light bulbs and room ACs, product bans and sell-through deadlines, court challenges and rollbacks, Energy Star program changes, specification updates and delistings, state appliance standards beyond federal rules, buy-before-the-deadline price effects, manufacturer discontinuations and new model availability, utility rebates tied to the standards and label and testing rule changes, with the product, agency or rule first and the effect on what a household can buy and what it costs.