Final answer:
A national government can implement energy efficiency policies through setting minimum energy standards, offering financial incentives like tax rebates, and initiating public sector energy-saving measures. These actions promote energy-efficient products and behaviors without relying on product labeling schemes.
Step-by-step explanation:
Three approaches that a national government can implement to enforce energy efficiency policy, other than mandatory product labeling schemes, include:
Setting Minimum Energy Standards: This command-and-control policy requires that products meet specific energy efficiency criteria before they can be sold. For example, the government may set rules on the minimum energy performance for appliances and vehicles.
Financial Incentives: The government can provide tax credits or rebates for consumers and businesses that purchase or install energy-efficient technologies. This approach encourages adoption by making it financially attractive to choose products that consume less energy.
Public Sector Initiatives: Lead by example by implementing energy-saving measures within government buildings and operations. This might entail retrofitting public facilities with energy-efficient lighting or heating systems to demonstrate the potential savings and encourage wider adoption.
To address the reference question, of the two approaches mentioned, commanding domestic auto companies to improve emissions by 2020 and setting national water quality standards are examples of command-and-control policies, whereas selling permits to emit a specified quantity of pollution is a market incentive-based approach.