Final answer:
Reducing electricity consumption in the least-cost way implies minimizing the cost of achieving the given reduction. The command-and-control policy is the approach of mandating specific technologies, while green energy emphasizes the use of clean and renewable alternative energy sources.
Step-by-step explanation:
To an economist, reducing electricity consumption in the least-cost way implies minimizing the cost of achieving a given reduction. This means choosing strategies that offer the greatest reduction in electricity consumption for the lowest cost, rather than implementing blanket mandates or subsidies without considering their economic efficiency.
Considering the two approaches to reducing emissions of CO₂ from manufacturing industries, the first approach where the U.S. government makes it a policy to use only predetermined technologies is the command-and-control policy. This policy mandates specific measures rather than allowing for market flexibility or the promotion of green technologies based on their efficiency or cost-effectiveness.
Green energy is related to finding new ways to harness clean and renewable alternative energy sources, which is a necessary component for reducing energy consumption in an environmentally-friendly manner. In promoting energy conservation, it’s most cost-effective to limit the use of high-power devices that operate for long periods and to use devices with greater efficiencies, like the compact fluorescent light bulb.